Dissertations / Theses: 'Sorghum bicolour'

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Pitso, Teele. "Improvements in the viability and fertilizing integrity of boar spermatozoa using the "umqombothi" sorghum bicolour semen extenders." Thesis, [Bloemfontein?] : Central University of Technology, Free State, 2009. http://hdl.handle.net/11462/130.

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Thesis (M. Tech. (Agric. Animal Prod.)) -- Central University of technology, Free State, 2009
The objective of this study was to evaluate the viability of semen extended in “Umqombothi” (UMQ) and compare with Beltsville Thawing Solution (BTS) and unextended semen (UNX). Twelve large white boars and twelve large white sows were used in this experiment. The following sperm characteristics were measured; sperm motility percentage, live sperm, sperm concentration, abnormal sperm percentage and semen pH of (UNX), (UMQ) and (BTS) and compared, fertility parameters namely; non-return rate percentage, farrowing rate, total piglets and live piglets were also measured and compared. The results from the study showed a significant difference (p<0.05) in sperm motility between (UNX), (UMQ) and (BTS) whereby (UMQ) had the highest percentage of motile sperm which was followed by (BTS) and (UNX) having the lowest percentage of motile sperm, however the results also showed that sperm motility and live sperm percentage of semen stored at 4°C differed significantly (p<0.05) from sperm motility and live sperm percentage of semen stored at 25°C whereby sperm motility and live sperm percentage of semen stored at 25°C were higher than sperm motility and live sperm percentage of semen stored at 4°C. Nevertheless no significant difference in sperm concentration and semen pH was found when semen stored at 4°C and 25°C were compared. However were time of semen collection of 9:00 and 15:00 were compared no significant differences in sperm motility percentage, live sperm percentage, sperm concentration, abnormal sperm percentage and semen pH were observed. The study also revealed a significant difference (p<0.05) in non-return rate, farrowing rate, total piglets and live piglets between semen stored at 25°C and 4°C of which the results explain that semen stored at 25°C had a higher percentage of non-return rate , farrowing rate, total piglets and live piglets, however, Under (UNX) collected at 9:00 and 15:00 that there was no significant difference in no-return rate percentage, farrowing rate, total piglets and live piglets was observed when two times of semen collections were compared. Under (UMQ) collected at 9:00 and 15:00 there was also no significant difference in non-return rate percentage, farrowing rate, total piglets and live piglets observed when two times of semen collections were compared. Under (BTS) collected at 9:00 and 15:00 there was also no significant difference in non-return rate percentage, farrowing rate, total piglets and live piglets observed when two times of semen collections were compared. Nevertheless were semen extenders were compared (UNX) collected at 9:00 and 15:00 differed significantly (p<0.05) from (UMQ) and (BTS) collected at 9:00 and 15:00 whereby (UNX) had the lowest percentage of non-return rate, farrowing rate, total piglets and live piglets.

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Soler, Clélia. "Dynamique de la diversité génétique du sorgho repiqué (Sorghum bicolor ssp. bicolor) au Nord Cameroun : facteurs biologiques et anthropiques." Thesis, Montpellier 2, 2012. http://www.theses.fr/2012MON20223/document.

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En 1996, la FAO a reconnu le rôle des agriculteurs dans la construction des ressources génétiques. Dans ce contexte, l'objectif général du projet PLANTADIV, dans lequel s'inscrit cette thèse, est d'appréhender comment les facteurs anthropiques et biologiques interagissent et façonnent la diversité génétique des plantes cultivées dans le bassin du lac Tchad. Dans cette région, les populations ont mis au point une innovation agricole originale : l'utilisation en contre-saison de terres argileuses inondées pour repiquer du sorgho. Les variétés de sorgho repiqué sont capables de puiser dans les réserves hydriques du sol pour accomplir leur cycle végétatif en saison sèche sans autre apport d'eau. Le sorgho repiqué connaît un large développement dans la région depuis la moitié du XXe siècle. Le projet de thèse se focalise sur l'estimation de la diversité génétique des sorghos repiqués et sur les mécanismes biologiques et génétiques qui ont pu contribuer à sa structuration intra et inter variétale. Nous avons également entrepris de retracer l'histoire évolutive des sorghos repiqués en nous appuyant essentiellement sur des outils de génétique des populations pour discuter les hypothèses géographiques et historiques existantes. Cette étude a mis en évidence qu'au moins deux événements de dessaisonalisation avaient eu lieu à partir de sorghos pluviaux provenant de deux groupes génétiques différents. Les sorghos repiqués sont plus différenciés que les sorghos pluviaux. Ceci peut s'expliquer en partie par les pratiques paysannes : les sorghos pluviaux sont échangés plutôt via les amis, la famille et les voisins, alors que les sorghos repiqués le sont plutôt via les marchés. De par les nombreux échanges de semence entre les différentes populations humaines dans cette région, l'étude phylogénétique n'a pas permis de mettre en évidence le(s) lieu(x) d'origine de dessaisonalisation.La seconde partie de ce travail a été consacré à la biologie de la reproduction du sorgho repiqué. Les méthodes de calcul indirectes et directes ont montrées que le sorgho repiqué est, comme le sorgho pluvial, préférentiellement autofécondé. Le taux moyen chez le sorgho repiqué est cependant plus faible (1,8%) que pour le sorgho pluvial (12%). De même, les variations d'allofécondation entre des panicules d'un même type nommé semblent plus faibles que pour le sorgho pluvial. La dernière partie de la thèse est consacrée aux impacts des pratiques agricoles sur la structuration de la diversité génétique des sorghos repiqués à une échelle locale. Les analyses génétiques ont montré, que ce soit pour le village de Djongdong ou celui de Bouzar, situés à l'extrême Nord du Cameroun, que pour un agriculteur donné, chaque type nommé correspond à une entité génétique. De plus, un même morphotype chez différents agriculteurs correspond aussi à une entité génétique. Les modes de gestion des semences et les pratiques culturales ont été analysés, elles influencent peu la structuration de la diversité génétique du sorgho repiqué
In 1996, FAO has recognized the role of farmers in building and managing genetic resources. This work is part of the project PLANTADIV which main objective is to understand how biological and anthropogenic factors interact and shape diversity of cultivated plants in the Lake Chad Basin. In this region, people have developed an original agricultural innovation: the use in dry-season of flooded clay soils for transplanting sorghum. Transplanted sorghum varieties are able to tap into soil moisture reserves to complete their growth cycle in the dry-season without any water supply. Transplanted sorghum cultivation undertook a large development in the region since the middle of the XX century.The thesis project focuses on the estimation of the genetic diversity of planted sorghum and on biological and genetic mechanisms that may have contributed to its structuration both within and between landraces. We also undertook to trace the evolutionary history of planted sorghum by relying primarily on population genetics approaches to elaborate over geographical and historical hypotheses.This study revealed that at least two events of deseasonalization occurred from rain- sorghum pools from two different genetic groups. Differentiation of dry-season sorghum is stronger than that of rain-sorghum. This may be partially due to social practices: rainy sorghum are mainly exchanged through friends, families and neighbors as planted sorghum seeds are often obtain from markets. Extensive seed exchange between different human populations across the region may have blurred the geographical pattern of the genetic diversity, not allowing us to identify potential sites for deseasonalization.The second part of this work is devoted to the reproductive biology of dry-season sorghum. Direct and indirect estimation methods have shown that dry-season sorghum is, as rain sorghum, preferably selfing. Average level of out crossing is nevertheless lower in dry-season sorghum (1.8%) than it is in rain-sorghum (12%). Within landraces, variations are also smaller for dry-season sorghum than for rain-sorghum.The last part of the thesis is devoted to the impacts of agricultural practices on the structure of the genetic diversity of dry-season sorghum at a local scale. Genetic analyzes have shown that in both studied villages of Djongdong and Bouzar, located in the extreme north of Cameroon, each landrace named by a farmer corresponds to a genetic entity. In addition, the same morphological type among different farmers corresponds to a genetic entity. Modes of seed management and cultural practices were analyzed; they seem to have little influence on the structure of the genetic diversity of dry-season sorghum

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Maulana, Frank. "Analysis of cold tolerance in sorghum [Sorghum bicolor (L.) Moench]." Thesis, Kansas State University, 2011. http://hdl.handle.net/2097/9184.

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Master of Science
Department of Agronomy
Tesfaye Tesso
Cold temperature stress is an important abiotic constraint to grain sorghum production in temperate regions. In the United States, low temperature in late spring and early fall has limited sorghum production to a narrow growing period. Deployment of cold tolerance traits may widen this window and hence contribute to increased production. The objectives of this study were (1) to determine the effect of early and mid-season cold temperature stress on growth, phenology and yield components of sorghum, and identify key traits that are most sensitive to cold stress at seedling and flowering stages, and (2) to identify new sources of cold tolerance for use in breeding programs. Series of controlled environment (greenhouse/growth chamber) and field experiments were carried out. Three sorghum genotypes of variable response, Shan Qui Red (tolerant), SRN39 (susceptible) and Pioneer 84G62 (unknown) were subjected to cold (15/13ºC day/night) and normal (25/23ºC day/night) temperature at seedling (Experiment I) and flowering (Experiment II) stages. The genotypes were planted in a greenhouse using a 5L polytainer pots. Each pot consisted of a single plant and each plot was represented by three pots. A split-plot design with three replications was used in both experiments with temperature regimes as main plots and genotypes as sub-plots. Three days after emergence, experiment I plants were moved to the growth chamber and subjected to the designated temperature treatments. For experiment II, the treatments were assigned at heading stage immediately before anthesis had begun. The treatments lasted 10 d in both experiments. Data were collected on seedling characteristics and leaf chlorophyll content in experiment I, days to flowering, maturity, and yield components in both experiments, and anthesis duration in experiment II. For the field experiment, 150 sorghum germplasm collections of potential cold tolerance along with tolerant and susceptible checks were evaluated for emergence and seedling traits under early planting (April 13) at soil temperature of 20.1/13.4 ºC max/min. The normal temperature treatment was applied by planting at regular season (May 26) at soil temperature of 30.0/20.4ºC max/min. Twenty-four genotypes selected based on field emergence and seedling vigor were further screened under controlled environment. Early-season stress significantly reduced leaf chlorophyll content, all seedling traits (height, vigor and dry weight), and also delayed flowering and maturity. But it had no effect on final leaf number, plant height and yield components. Genotypic response to early stress was significant for all traits with the susceptible checks having the lowest score for all seedling traits. Mid-season cold stress prolonged anthesis duration, delayed maturity and highly reduced all yield components. Several genotypes among the 150 had higher seedling vigor and emergence than the tolerant check, Shan Qui Red. In conclusion, reduced seedling vigor as a result of early stress had no effect on final yield provided that stand establishment was not compromised while mid season stress is damaging to yield. The wide genetic variation for the traits indicates the potential for improvement of cold tolerance in sorghum.

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Sant, Rajnesh R. Prasad. "Development of a transformation system for sorghum (Sorghum bicolor L.)." Thesis, Queensland University of Technology, 2012. https://eprints.qut.edu.au/50977/1/Rajnesh_Sant_Thesis.pdf.

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Sorghum (Sorghum bicolor (L.) Moench) is the world’s fifth major cereal crop and holds importance as a construction material, food and fodder source. More recently, the potential of this plant as a biofuel source has been noted. Despite its agronomic importance, the use of sorghum production is being constrained by both biotic and abiotic factors. These challenges could be addressed by the use of genetic engineering strategies to complement conventional breeding techniques. However, sorghum is one of the most recalcitrant crops for genetic modification with the lack of an efficient tissue culture system being amongst the chief reasons. Therefore, the aim of this study was to develop an efficient tissue culture system for establishing regenerable embryogenic cell lines, micropropagation and acclimatisation for Sorghum bicolor and use this to optimise parameters for genetic transformation via Agrobacterium-mediated transformation and microprojectile bombardment. Using five different sorghum cultivars, SA281, 296B, SC49, Wray and Rio, numerous parameters were investigated in an attempt to establish an efficient and reproducible tissue culture and transformation system. Using immature embryos (IEs) as explants, regenerable embryogenic cell lines (ECLs) could only be established from cultivars SA281 and 296B. Large amounts of phenolics were produced from IEs of cultivars, SC49, Wary and Rio, and these compounds severely hindered callus formation and development. Cultivar SA281 also produced phenolics during regeneration. Attempts to suppress the production of these compounds in cultivars SA281 and SC49 using activated charcoal, PVP, ascorbic acid, citric acid and liquid filter paper bridge methods were either ineffective or had a detrimental effect on embryogenic callus formation, development and regeneration. Immature embryos sourced during summer were found to be far more responsive in vitro than those sourced during winter. In an attempt to overcome this problem, IEs were sourced from sorghum grown under summer conditions in either a temperature controlled glasshouse or a growth chamber. However, the performance of these explants was still inferior to that of natural summer-sourced explants. Leaf whorls, mature embryos, shoot tips and leaf primordia were found to be unsuitable as explants for establishing ECLs in sorghum cultivars SA281 and 296B. Using the florets of immature inflorescences (IFs) as explants, however, ECLs were established and regenerated for these cultivars, as well as for cultivar Tx430, using callus induction media, SCIM, and regeneration media, VWRM. The best in vitro responses, from the largest possible sized IFs, were obtained using plants at the FL-2 stage (where the last fully opened leaf was two leaves away from the flag leaf). Immature inflorescences could be stored at 25oC for up to three days without affecting their in vitro responses. Compared to IEs, the IFs were more robust in tissue culture and showed responses which were season and growth condition independent. A micropropagation protocol for sorghum was developed in this study. The optimum plant growth regulator (PGR) combination for the micropropagation of in vitro regenerated plantlets was found to be 1.0 mg/L BAP in combination with 0.5 mg/L NAA. With this protocol, cultivars 296B and SA281 produced an average of 57 and 13 off-shoots per plantlet, respectively. The plantlets were successfully acclimatised and developed into phenotypically normal plants that set seeds. A simplified acclimatisation protocol for in vitro regenerated plantlets was also developed. This protocol involved deflasking in vitro plantlets with at least 2 fully-opened healthy leaves and at least 3 roots longer than 1.5 cm, washing the media from the roots with running tap water, planting in 100 mm pots and placing in plastic trays covered with a clear plastic bag in a plant growth chamber. After seven days, the corners of the plastic cover were opened and the bags were completely removed after 10 days. All plantlets were successfully acclimatised regardless of whether 1:1 perlite:potting mix, potting mix, UC mix or vermiculite were used as potting substrates. Parameters were optimised for Agrobacterium-mediated transformation (AMT) of cultivars SA281, 296B and Tx430. The optimal conditions were the use of Agrobacterium strain LBA4404 at an inoculum density of 0.5 OD600nm, heat shock at 43oC for 3 min, use of the surfactant Pluronic F-68 (0.02% w/v) in the inoculation media with a pH of 5.2 and a 3 day co-cultivation period in dark at 22oC. Using these parameters, high frequencies of transient GFP expression was observed in IEs precultured on callus initiation media for 1-7 days as well as in four weeks old IE- and IF-derived callus. Cultivar SA281 appeared very sensitive to Agrobacterium since all tissue turned necrotic within two weeks post-exposure. For cultivar 296B, GFP expression was observed up to 20 days post co-cultivation but no stably transformed plants were regenerated. Using cultivar Tx430, GFP was expressed for up to 50 days post co-cultivation. Although no stably transformed plants of this cultivar were regenerated, this was most likely due to the use of unsuitable regeneration media. Parameters were optimised for transformation by particle bombardment (PB) of cultivars SA281, 296B and Tx430. The optimal conditions were use of 3-7 days old IEs and 4 weeks old IF callus, 4 hour pre- and post-bombardment osmoticum treatment, use of 0.6 µm gold microparticles, helium pressure of 1500 kPa and target distance of 15 cm. Using these parameters for PB, transient GFP expression was observed for up to 14, 30 and 50 days for cultivars SA281, 296B and Tx430, respectively. Further, the use of PB resulted in less tissue necrosis compared to AMT for the respective cultivars. Despite the presence of transient GFP expression, no stably transformed plants were regenerated. The establishment of regenerable ECLs and the optimization of AMT and PB parameters in this study provides a platform for future efforts to develop an efficient transformation protocol for sorghum. The development of GM sorghum will be an important step towards improving its agronomic properties as well as its exploitation for biofuel production.

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Barnaud, Adeline. "Savoirs, pratiques et dynamiques de la diversité génétique : le sorgho (Sorghum bicolor ssp. bicolor) chez les Duupa du nord Cameroun." Montpellier 2, 2007. http://www.theses.fr/2007MON20103.

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Yüksel, Osman Balabanlı Cahit. "Sorgum x Sudanotu (Sorghum bicolor (L.) Moench x Sorghum sudanense (Piper)Stapf) Melezinde farklı azot dozu uygulamalarının verim ve bazı kalite özelliklerine etkileri /." Isparta: SDÜ Fen Bilimleri Enstitüsü, 2006. http://tez.sdu.edu.tr/Tezler/TF00978.pdf.

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Nganwa, Patience Jennifer Kengyeya. "Enzymes with biocatalytic potential from Sorghum bicolor." Thesis, Rhodes University, 2000. http://hdl.handle.net/10962/d1003967.

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Sorghum is a staple food in the semi-arid tropics of Asia and Africa, sustaining the lives of the poorest rural people. This project set out to improve the potential economic value of Sorghum bicolor as a crop. The task was undertaken by screening for selected enzymes in the plant that would have a potential market for use in industrial applications and in biotransformations, specifically proteases, polyphenol oxidases and peroxidases. Asurveywas conducted using standard enzyme assays and crude plant extracts, to determine whether the selected enzymes were present. Grain tissue did not appear to have significant protease or polyphenoloxidase activity, but high levels of peroxidases were detected, withthe young grain extracts showing more activity(4.63U/mL)thanripegrain extracts (0.62 U/mL). Leaf tissue extracts contained low levels of protease activity, a considerable amount of polyphenol oxidase (0.127 U/mL), and peroxidase (4.7 U/mL) activities comparable with that found in grain tissue. Root tissue extract was found to contain the highest levels of peroxidase activity (7.8 U/mL) compared to the other extracts. Therefore, sorghum peroxidase from the root was isolated, purified, characterized and applied to biotransformation reactions. Different sorghum strains,withvaryinggraincolour, (Zimbabwe - bronze, Seredo - brown and Epurpur - cream/white) were investigated for the presence of polyphenol oxidase and peroxidase activities. Results of spectrophotometric analysis showed that the enzymes did not appear to be strain specific. However, gel electrophoresis analysis revealed differences in band patterns among the strains. Partial purification of sorghum root peroxidase was achieved after centrifugation, extraction with polyvinylpolypyrrolidone (PVPP), ultrafiltration, and hydrophobic chromatography with phenyl Sepharose, followed by polyacrylamidegelelectrophoresis (PAGE). The specific activity of the 5-fold purified enzyme was found to be 122.3 U/mg. After PAGE analysis, two bands with molecular weights of approximately 30 000 and 40 000 were detected, which compares well with horse radish peroxidase (HRP) which has a molecular weight of approximately 44 000. The colour intensity of the bands in the activity gels indicated that sorghum root peroxidase had apparently higher levels of peroxidase activity than commercial horseradish peroxidase (HRP). Characterizationexperiments revealed that sorghumroot peroxidase is active over a broad temperature range and remains active at temperatures up to 100°C. It also has a broad substrate range. The optimum pH of the enzyme was found to be pH 5 - 6. Under standardized assay conditions, the optimal substrate concentration, using o-dianisidine as substrate, was 50 mM, and the optimal H2O2 concentration under these conditions was found to be 100 mM. Sorghum root peroxidase was applied in a preliminary investigation into the oxidative biotransformationof a number of aromatic compounds. The products obtained were comparable withthose whenthe compounds are reacted with HRP which is the most commonly used commercial peroxidase and has been extensively studied. However, HRP is relatively costly, and the use of peroxidase from sorghum roots as an alternative source, appears to be promising. A patent has been provisionally registered, covering application of sorghum root peroxidase for biotransformations.

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Emendack, Yves Yatou. "Drought performance of millet (Panicum miliaceum) and sorghum (Sorghum bicolor (L.) Moench)." Berlin dissertation.de, 2007. http://www.dissertation.de/buch.php3?buch=5025.

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Al-Soqeer, Abdulrahman A. "The potential of seed soaking in sorghum (Sorghum bicolor L. Moench) production." Thesis, University of Nottingham, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408443.

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AGBARY, ABDUL WALLY. "HERITABILITY AND PHYSIOLOGY OF DROUGHT TOLERANCE IN SORGHUM (SORGHUM BICOLOR (L.) MOENCH)." Diss., The University of Arizona, 1985. http://hdl.handle.net/10150/187991.

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Physiological responses of 12 sorghum (Sorghum bicolor L.) genotypes previously classified as drought resistant and susceptible upon grain yield basis were evaluated under dry and wet moisture treatments at Tucson, Arizona in 1983. In addition, the relationship of these physiological responses and their heritability estimates were also determined. Apparent photosynthesis, transpiration, diffusive resistance, temperature differentials, and leaf temperature were measured under field conditions at three intervals from planting date: 48, 62, and 77 days, respectively. Stomatal density and epicuticular wax content were determined toward the end of the season when full canopy development was reached. Stress significantly affected all characteristics measured for each genotype by a reduction in apparent photosynthesis rates, transpiration, and temperature differentials, and an increase in diffusive resistance, leaf temperature and stomatal density. The wax content response varied among genotypes irrespective of the dry and wet moisture treatments. Except for the wax content and stomatal density, all the other parameters demonstrated a high significant correlation with photosynthesis at .001 level; nevertheless, greater values were observed in the stress treatment. Analysis of variance failed to detect significant differences among the 12 germplasm sources, except for the stomatal density. Multiple regression analysis showed that leaf diffusive resistance was the first variable incorporated for photosynthesis prediction in both the dry and wet treatments. The offspring and mid-parent regression for each characteristic under both treatments provided heritability estimates (h('2) (+OR-) SE), indicating higher heritability values under the dry treatment.

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Ayyaru, Thevar Prasanna. "Determining transpiration efficiency of eight grain sorghum lines [Sorghum bicolor (L.) Moench]." Thesis, Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/1094.

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Herde, Damian. "Inheritance and mechanisms of resistance of sorghum (Sorghum bicolor) to Sorghum ergot (caused by Claviceps africana) /." [St. Lucia, Qld.], 2006. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19680.pdf.

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Ollitrault, Patrick. "Évaluation génétique des Sorghos cultivés (Sorghum bicolor L. Moench) par l'analyse conjointe des diversités enzymatique et morphophysiologique : relations avec les sorghos sauvages." Paris 11, 1987. http://www.theses.fr/1987PA112041.

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Les données morphologigues, cytogénétiques et historiques n'ont pas permis d'éclaircir totalement l'organisation génétique et l'évolution des sorghos cultivés. L'électrophorèse enzymatique est, à l'heure actuelle, un des outils les plus performants pour les études de génétique des populations et de phylogénie. Douze systèmes enzymatiques polymorphes ont été mis au point. L'interprétation génétique des zymogrammes fait intervenir 77 allèles pour 24 locus polymorphes. Les hypothèses de déterminisme sont testées et confirmées pour 8 locus sur des descendances F2. Par ailleurs, l'étude des taux de recombinaison met en évidence un groupe de linkage concernant trois locus (PXC3, LAP2, PA2). L'analyse du polymorphisme enzymatique intra et inter-population de 80 variétés prospectées au Burkina Faso témoigne du comportement sélectivement neutre, au niveau allélique, des marqueurs étudiés. La diversité intra-population est élevée (30 % du total) et semble entretenue par la migration, une allogamie relativement forte (10 à 30 %) et des effets d'hétérosis. D'après des simulations informatiques, ces facteurs combinés au mode traditionnel de renouvellement des semences entraînent, pour les guinea, une grande instabilité évolutive de la diversité enzymatique intra-population. L'évaluation génétique de la section Sorghum est basée sur l'étude de la diversité enzymatique de 348 variétés traditionnelles et de 56 écotypes sauvages. Elle met en évidence une structuration génétique des sorghos cultivés autour de trois pôles géographiques. L'analyse morphophysiologique de 158 variétés traditionnelles recoupe en revanche la classification de HARLAN et DE WET (1972). Un schéma de domestication est proposé pour rendre compte de cette organisation. La classification HARLAN et DE WET (1972) apparaît finalement davantage comme une description phénotypique que génétique. Elle pourrait être complétée par une classification polithétique sur les caractéristiques enzymatiques pour obtenir une bonne évaluation génétique des collections de sorghos cultivés. L'ensemble de ce travail ouvre des perspectives prometteuses tant dans le domaine des ressources génétiques que de la sélection.

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Ollitrault, Patrick. "Evaluation génétique des sorghos cultivés (Sorghum bicolor L. Moench) par l'analyse conjointe des diversités enzymatique et morphophysiologique relations avec les sorghos sauvages /." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37608533n.

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Odra, J. G. "Physiological investigations of drought and heat resistance in sorghum (Sorghum bicolor (L.) Moench." Thesis, University of Newcastle Upon Tyne, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370627.

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Khalif, Ahmed Sheikh Hassan. "GERMINATION RESPONSES OF SORGHUM VARIETIES (SORGHUM BICOLOR L. MOENCH) TO FUNGICIDE SEED TREATMENTS." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/275262.

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Mahaman, Sabiou 1957. "Nitrogen requirements of grain sorghum (Sorghum bicolor (L.) Moench) under soil moisture stress." Thesis, The University of Arizona, 1990. http://hdl.handle.net/10150/277251.

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Water and fertilizers are the two major agricultural inputs limiting yields in the arid and semi-arid regions of the world. Proper knowledge of their influence on crops should be obtained for appreciable returns. Therefore, a field study was conducted to evaluate the effects of four nitrogen (N) treatments (0, 56, 112, and 168 kg N/ha), two water (M) levels (39 and 58 cm), and two varieties (V) (Funks G-522DR and Conlee Rusler) on dry matter production, total N concentration, and yield of grain sorghum (Sorghum bicolor (L.) Moench). Total N concentration, dry matter, and grain yield were increased by N treatments. Generally, the highest N rate gave the most significant effects; the other rates had statistically the same responses. Varieties were different in their dry matter and grain yields, but had the same total nitrogen contents, as was suggested by the ANOVA and means analysis. There were no detectable interactions among the factors. Moisture had minimal effect on dry matter and grain yields, but influenced total N concentration significantly. Nitrogen contents increased with the higher moisture level.

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Aydin, Selahattin. "The relationship between grain yield and waxy endosperm in Sorghum bicolor (Linn.) Moench." Diss., Texas A&M University, 2003. http://hdl.handle.net/1969.1/2256.

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In sorghum, a single recessive gene Wx conditions waxy endosperm type. While parental inbred lines and hybrids with waxy endosperm have been developed, there has been little to no adoption of these hybrids by producers, primarily because waxy hybrids consistently yield 5-10% less than non-waxy hybrids and end-use buyers will not pay for the utilization benefits. While current waxy germplasm does not yield competitively at this time, there is a question as to whether the yield reduction is due to a negative relationship between waxy per se or due to the lack of effort to develop high yielding waxy germplasm. The purpose of this study is to determine the relationship between the waxy endosperm phenotype and grain yield in sorghum. From each of two F2 breeding populations segregating for waxy endosperm, 50 inbred lines were derived, selected only for homozygosity of endosperm type. No selection for yield was practiced during the development of these lines. Approximately 25 waxy and 25 non-waxy lines were selected for further evaluation from each population. These lines and a set of testcross hybrids were evaluated in four environments. When combined across environments and populations, waxy inbred lines and hybrids yielded 17% less than non-waxy inbred lines and hybrids. However, analysis of the individual inbred lines and hybrids indicated that several waxy inbred lines were competitive in yield with the best non-waxy genotypes. The results indicate that it should be possible to develop waxy hybrids that are competitive in yield, but that this will require additional breeding efforts to identify the correct inbred lines and hybrids.

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19

Philippe, Romain. "Diversité et évolution des Asr, gènes candidats pour la tolérance à la sécheresse, chez le riz (Oryza sativa) et le sorgho (Sorghum bicolor ssp. Bicolor)." Montpellier 2, 2009. http://www.theses.fr/2009MON20037.

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20

Oliveira, Viviane Pinho de. "Caracteres fisiolÃgicos e bioquÃmicos de Sorghum bicolor E Sorghum sudanense sob condiÃÃes de salinidade." Universidade Federal do CearÃ, 2011. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8865.

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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
Este trabalho teve por finalidade avaliar algumas variÃveis fisiolÃgicas e bioquÃmicas de duas espÃcies de sorgo forrageiro submetidas a diferentes condiÃÃes de cultivo e de salinidade. Para isso, foram montados dois experimentos. No primeiro deles estudou-se tais variÃveis em Sorghum bicolor e Sorghum sudanense, em funÃÃo de diferentes nÃveis de estresse salino, enquanto no segundo, as variÃveis foram estudadas em duas fases distintas de desenvolvimento das duas espÃcies de sorgo, visando determinar em qual delas essas espÃcies sÃo mais resistentes aos efeitos deletÃrios da salinidade. No primeiro experimento, os tratamentos foram dispostos em esquema fatorial 2 Ã 5, composto por duas espÃcies (S. bicolor e S. sudanense) e cinco tratamentos (NaCl a 0, 25, 50, 75 e 100 mM). Nesse experimento, os parÃmetros de trocas gasosas foram pouco afetados pela salinidade, em ambas as espÃcies. O crescimento das plantas de ambas as espÃcies reduziu Ã medida que a salinidade aumentou. O potencial osmÃtico (s) foliar foi fortemente reduzido pela salinidade nessas plantas, a qual aumentou significativamente a concentraÃÃo de solutos orgÃnicos nas duas espÃcies de sorgo. As concentraÃÃes de Na+ e Cl- aumentaram com a salinidade em ambas as espÃcies. S. bicolor e S. sudanense mantiveram o teor relativo de Ãgua sob condiÃÃes salinas igual ao do controle. Nas espÃcies de sorgo estudadas, os carboidratos solÃveis e os Ãons K+ e Cl- foram os que mais contribuÃram para o ajustamento osmÃtico das plantas. Nas folhas de S. bicolor, houve um aumento na atividade das peroxidases do ascorbato (APX) e do guaiacol (GPX) e uma reduÃÃo na atividade da catalase (CAT), enquanto a dismutase do superÃxido (SOD) nÃo foi afetada. Em S. sudanense, Ã medida que foram elevadas as doses de NaCl, observou-se um aumento na atividade da GPX e da SOD. Nas raÃzes, apenas a SOD apresentou aumento em atividade no S. bicolor. A atividade ribonucleÃsica nas folhas de ambas as espÃcies aumentou com as doses crescentes de NaCl, enquanto que nas raÃzes, ela foi reduzida Ã medida que o estresse salino intensificou-se. No segundo experimento, os tratamentos foram arranjados em esquema fatorial 2 Ã 3 Ã 2, composto por duas espÃcies (S. bicolor e S. sudanense), trÃs concentraÃÃes de sais na Ãgua de irrigaÃÃo (condutividades elÃtricas de 0,0; 4,0 e 8,0 dS m-1) e dois perÃodos de aplicaÃÃo do estresse salino Ãs plantas [desde a semeadura atÃ 25 dias depois (Fase I) e do 25Â ao 50Â dia apÃs a semeadura (Fase II)], com cinco repetiÃÃes. As principais alteraÃÃes nas trocas gasosas ocorreram na Fase II do desenvolvimento. O estresse salino reduziu o crescimento das plantas de sorgo em ambas as fases de desenvolvimento, porÃm essa reduÃÃo foi mais acentuada na Fase I. Os teores dos solutos orgÃnicos variaram em funÃÃo das fases de desenvolvimento, da espÃcie e da salinidade. Na Fase I, em ambas as espÃcies de sorgo, houve acrÃscimos nos teores de Na+ e K+ e reduÃÃo nos de Cl- pela salinidade, enquanto que, na Fase II do desenvolvimento, os teores de Na+ e K+ foram reduzidos e os de Cl-, aumentados, tanto em S. bicolor como em S. sudanense. Na Fase I do desenvolvimento, apenas a SOD, em S. bicolor, e a CAT, em S. sudanense, mostraram incrementos de atividade em resposta ao estresse salino. JÃ na Fase II, nenhum aumento na atividade do sistema enzimÃtico antioxidativo foi observado em funÃÃo da salinidade, nas duas espÃcies estudadas. Na Fase I, a atividade da RNase, em ambas as espÃcies, foi reduzida com a salinidade, enquanto na Fase II do desenvolvimento, ela foi aumentada. O crescimento das plantas de S. sudanense foi ligeiramente mais afetado que o de S. bicolor. As espÃcies de sorgo forrageiro estudadas neste trabalho foram capazes de reduzir o s foliar em concentraÃÃes elevadas de NaCl, o que pode ter contribuÃdo para um melhor ajustamento osmÃtico. AlÃm disso, nas condiÃÃes empregadas no primeiro experimento, S. bicolor pareceu ter um sistema antioxidante mais eficaz contra os efeitos da salinidade do que S. sudanense. Em relaÃÃo ao segundo experimento, o crescimento das plantas de sorgo forrageiro foi mais afetado quando o estresse salino foi aplicado em estÃdios iniciais do desenvolvimento. O estresse oxidativo causado pela salinidade parece nÃo ter sido suficiente para estimular o sistema de defesa enzimÃtico antioxidativo na Fase II do desenvolvimento, em ambas as espÃcies. AlÃm disso, o aumento na atividade RNÃsica pode indicar o papel desta enzima na proteÃÃo contra os efeitos deletÃrios da salinidade nessas espÃcies de sorgo. De modo geral, nÃo houve diferenÃas marcantes na tolerÃncia das plantas de S. bicolor e S. sudanense Ã salinidade.
This study aimed to evaluate some physiological and biochemical variables of two species of sorghum subjected to different growing conditions and salinity. For this, two experiments were set up. In the first study, the variables in Sorghum bicolor and Sorghum sudanense were evaluated according different levels of salinity stress. In the second, the variables were studied in two distinct phases of development of two species of sorghum, to determine which one of these species are more resistant to the deleterious effects of salinity. In the first experiment, treatments were arranged in a 5 Ã 2 factorial, consisting of two species (S. bicolor and S. sudanense) and five treatments (NaCl at 0, 25, 50, 75 and 100 mM). In this experiment, the gas exchange parameters were little affected by salinity in both species. Plant growth of both species decreased as salinity increased. The osmotic potential (ψs) leaves was strongly reduced by salinity in these plants, which significantly increased the concentration of organic solutes in the two species of sorghum. The concentrations of Na+ and Cl- increased with salinity in both species. S. bicolor and S. sudanense maintained relative water content under saline conditions the same as the control. In sorghum species studied, the soluble carbohydrates and the ions K+ and Cl- were the main contributors to the osmotic adjustment of plants. In leaves of S. bicolor, there was an increase in activity of ascorbate peroxidase (APX) and guaiacol (GPX) and a reduction in activity of catalase (CAT), while superoxide dismutase (SOD) was not affected. In S. sudanense, the activity of GPX and SOD increased with increasing salinity. In roots, just SOD activity in S. bicolor were increased with salt stress. Ribonuclease activity in the leaves of both species increased with increasing doses of NaCl, whereas in roots it was reduced as the salt stress intensified. In the second experiment, treatments were arranged in a factorial 2 Ã 3 Ã 2, composed of two species (S. bicolor and S. sudanense), three concentrations of salts in irrigation water (electrical conductivities of 0.0, 4.0 and 8.0 dS m-1) and two periods of application of salt stress to plants [from sowing until 25 days later (Phase I) and from 25th to 50th day after sowing (Phase II)], with five repetitions. The main changes in gas exchange occurred in Phase II development. The salt stress reduced plant growth of sorghum in both phases of development, but this reduction was more pronounced in Phase I. The levels of organic solutes varied according to the phases of development, species and salinity. In Phase I, in both species of sorghum, there were increases in levels of Na+ and K+ and reduced Cl- by salinity, whereas in Phase II development, the levels of Na+ and K+ were reduced and Cl- extended, both in S. bicolor as in S. sudanense. In Phase I of development, only SOD in S. bicolor, and CAT in S. sudanense showed activity increases in response to salt stress. In the Phase II, no increase in the activity of antioxidant enzyme system was observed as a function of salinity in both species. In Phase I, the activity of RNase in both species was reduced by salinity, while in Phase II development, it was expanded. Plant growth of S. sudanense was slightly more affected than the S. bicolor. Sorghum species studied in this work were able to reduce the leaf ψs high concentrations of NaCl, which may have contributed to a better osmotic adjustment. In addition, under the conditions employed in the first experiment, S. bicolor appeared to have a more effective antioxidant system against the effects of salinity than S. sudanense. For the second experiment, the growth of sorghum plants was more affected when the salt stress was applied in the early stage of development. The oxidative stress caused by salinity seems to have been sufficient to stimulate the enzymatic antioxidant defense system in Phase II development in both species. Furthermore, increased activity RNase may indicate the role of this enzyme in protecting against the deleterious effects of salinity in these species of sorghum. Overall, there were no marked differences in plant tolerance between S. bicolor and S. sudanense under salinity.

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21

Chamba, Emmanuel Boache. "Biochemical analysis and molecular cloning of methionine-rich proteins of sorghum (Sorghum bicolor) seed." Thesis, University of Bristol, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.437276.

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22

Maulana, Frank. "Agronomic, genetic and genomic approaches for predicting heterosis in sorghum [Sorghum bicolor (L.) Moench]." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/32810.

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Doctor of Philosophy
Department of Agronomy
Tesfaye Tesso
The approach used to identify inbred lines that can produce superior hybrids is costly and time-consuming. It requires creation of all possible crosses and evaluation of the crosses to estimate combining abilities for the desired traits. Predicting heterosis or hybrid performance in any way possible may help to reduce the number of crosses to be made and evaluated. In this study, four sets of experiments were conducted to determine whether heterosis can be predicted based on inbred line performance, genetic distance between parents and genomic prediction model. The first experiment was aimed at assessing the levels of genetic diversity, population structure and linkage disequilibrium (LD) in 279 public sorghum inbred lines, based on 66,265 SNPs generated using the genotyping-by-sequencing (GBS) platform. The inbred lines were developed at different times over the last two decades and harbor robust diversity in pedigree and agronomic characteristics. Some of the inbreds are resistant to Acetolactate synthase (ALS) and Acetyl co-enzyme-A carboxylase (ACC) inhibitor herbicides. The mean polymorphic information content (PIC) and gene diversity across the entire inbreds were 0.35 and 0.46, respectively with non-herbicide resistant inbreds harboring more diversity than the herbicide resistant ones. The population structure analysis clustered the inbred lines into three major subgroups according to pedigree and fertility-reaction with the maintainer lines (B-lines) distinctly forming a separate cluster. Analysis of molecular variance (AMOVA) revealed more variation within subgroups than among subgroups. Substantial linkage disequilibrium (LD) was detected between the markers in the population with marked variation between chromosomes. This information may facilitate the use of the inbreds in sorghum breeding programs and provide perspectives for optimizing marker density for gene mapping and marker-assisted breeding. The second experiment, based on 102 F1 hybrids developed by intercrossing closely and distantly related inbreds, was conducted to investigate the relationship of genetic distance between parents with hybrid vigor or heterosis. The F1 hybrids alongside their parents were evaluated at two environments in a randomized complete block design with three replications. The results show that correlations of genetic distance between parents with hybrid performance and heterosis were variable and dependent on the trait. Though most were statistically non-significant and not strong to be used as predictor for heterosis, the results tend to show that certain level of genetic distance between parents is needed to capture maximum heterosis and hybrid performance. The objective of the third research study was to determine whether traits measured on parents can be used to predict hybrid performance in sorghum and to assess the combining ability of selected inbreds. Forty-six parental inbred lines and 75 F1 hybrids generated from intercrossing the inbreds were evaluated in four environments in a randomized complete block design with three replications. The average performance of the parents (mid-parent) was significantly correlated with hybrid performance for thousand kernel weight, days to flowering and plant height. Significant general (GCA) and specific (SCA) combining abilities were observed for most traits, with highly significant GCA effects observed for most traits as compared to SCA indicating that additive genetic effects are more important in affecting the inheritance of the traits measured. Results show that studying parental inbred line performance could generate important information for predicting hybrid performance in sorghum. The fourth experiment was aimed at assessing the efficacy of genomic prediction of hybrid performance in sorghum. Genomic prediction was performed with five-fold cross-validation procedure on 204 F1 hybrids developed using 102 inbred lines. A total of 66,265 SNP markers generated using genotyping-by-sequencing were used in this study. Results showed that increasing training population size increased prediction accuracies for all traits with the effect being different for different traits. Also, considering additive effects alone versus additive and dominance effects in the model showed similar trend of prediction accuracy but the full model (considering both additive and dominance effects of the markers) provided better prediction at least for some of the traits. The results suggest that genomic prediction could become an effective tool for predicting the performance of untested sorghum hybrids thus adding efficiency to hybrid selection.

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23

Hlophe, Hanson Boy. "Sweet sorghum (Sorghum bicolor (L.) Moench) response to supplemental irrigation in different growth stages." Diss., University of Pretoria, 2014. http://hdl.handle.net/2263/43352.

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Sweet sorghum (Sorghum bicolor (L.) Moench) is a high biomass and sugar-yielding crop. There is recently an interest in sweet sorghum as feedstock for ethanol production, since it is rich in sugars, and reportedly has low nutrition and water requirements. A field experiment was conducted at Hatfield Experiment farm of the University of Pretoria, South Africa in 2010/11. The aim of the study was to evaluate sweet sorghum performance under different water regimes and determine their effect on biomass and sugar yields. Four water treatments (Control, Supplemental irrigation at early vegetative stage (EVS), Supplemental irrigation at late vegetative stage (LVS) and Dry land. One sweet sorghum variety (Sugar graze) was used in the experiment. Plant height, leaf area index (LAI) and dry matter accumulation were measured periodically through growth analysis. This data was used to calibrate the Soil Water Balance (SWB) crop model for sweet sorghum. Brix and quality analysis were carried out by the ACCI laboratory at the University of KwaZulu Natal at final harvest. Total fresh biomass production (t ha-1) of sweet sorghum was significantly improved by full irrigation (Control) and supplemental irrigation at either the early vegetative stage (EVS) or late vegetative stage (LVS), compared to the Dry land treatment. This shows that with supplemental irrigation higher fresh biomass production can be attained. The Control and Supplemental irrigation at early vegetative stage (EVS) treatments gave the highest fresh stalk yield (16.6 ton ha-1 and 17.1ton ha-1 respectively) at harvest, followed by the Dry land and Supplemental irrigation at late vegetative stage (LVS) treatments. However, the three irrigated treatments did not differ significantly from each other with regard to total biomass production. It should be noted that the experiment was conducted during a wet season (total rainfall of 757mm during the growing period), which may have contributed to the limited response of the crop to applied water treatments. Water treatments had no significant effect on total dry matter yield. Although the differences among the water treatments were not significant, a slightly higher dry matter yield was obtained for EVS. Similarly, total sugar yield (t ha-1) and theoretical ethanol yield (L ha-1) were not significantly influenced by water treatments. Sugar yields ranged between 1.64 and 2.77 t ha-1 and ethanol yields between 1763 and 2984 L ha-1. The results also showed that treatments that were irrigated until late in the season (Control and LVS) had lower stalk dry matter contents (% DM) than both EVS and Dry land treatments. This probably resulted in lower sugar (t ha-1) and ethanol yields (L ha-1) for these treatments, although high fresh stalk yields were obtained. Brix (t/ha) was greatly influenced by irrigation as there were significant differences between all the water treatments. Based on these results, the main objective was achieved since it was clear that irrigating during the early stages of plant growth ensured optimum results in terms of biomass yield, sugar and ethanol yield. Model simulation results for top and harvestable dry matter and leaf area index of all the irrigation treatments were within reasonable accuracy and statistical parameters were generally acceptable. Soil water deficits were not so well simulated, especially during dry periods when simulated deficits were much higher than measured values. Nonetheless, it can be concluded that the SWB model should be a useful tool for scenario modelling in order to estimate sweet sorghum production and water use under a wide range of conditions.
Dissertation (MScAgric)--University of Pretoria, 2014.
lk2014
Plant Production and Soil Science
MScAgric
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24

Oliveira, Viviane Pinho de. "Caracteres fisiológicos e bioquímicos de Sorghum bicolor E Sorghum sudanense sob condições de salinidade." reponame:Repositório Institucional da UFC, 2011. http://www.repositorio.ufc.br/handle/riufc/18811.

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OLIVEIRA, Viviane Pinho de. Caracteres fisiológicos e bioquímicos de Sorghum bicolor E Sorghum sudanense sob condições de salinidade. 2011. 143 f. Tese (Doutorado em bioquímica)- Universidade Federal do Ceará, Fortaleza-CE, 2011.
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This study aimed to evaluate some physiological and biochemical variables of two species of sorghum subjected to different growing conditions and salinity. For this, two experiments were set up. In the first study, the variables in Sorghum bicolor and Sorghum sudanense were evaluated according different levels of salinity stress. In the second, the variables were studied in two distinct phases of development of two species of sorghum, to determine which one of these species are more resistant to the deleterious effects of salinity. In the first experiment, treatments were arranged in a 5 × 2 factorial, consisting of two species (S. bicolor and S. sudanense) and five treatments (NaCl at 0, 25, 50, 75 and 100 mM). In this experiment, the gas exchange parameters were little affected by salinity in both species. Plant growth of both species decreased as salinity increased. The osmotic potential (ψs) leaves was strongly reduced by salinity in these plants, which significantly increased the concentration of organic solutes in the two species of sorghum. The concentrations of Na+ and Cl- increased with salinity in both species. S. bicolor and S. sudanense maintained relative water content under saline conditions the same as the control. In sorghum species studied, the soluble carbohydrates and the ions K+ and Cl- were the main contributors to the osmotic adjustment of plants. In leaves of S. bicolor, there was an increase in activity of ascorbate peroxidase (APX) and guaiacol (GPX) and a reduction in activity of catalase (CAT), while superoxide dismutase (SOD) was not affected. In S. sudanense, the activity of GPX and SOD increased with increasing salinity. In roots, just SOD activity in S. bicolor were increased with salt stress. Ribonuclease activity in the leaves of both species increased with increasing doses of NaCl, whereas in roots it was reduced as the salt stress intensified. In the second experiment, treatments were arranged in a factorial 2 × 3 × 2, composed of two species (S. bicolor and S. sudanense), three concentrations of salts in irrigation water (electrical conductivities of 0.0, 4.0 and 8.0 dS m-1) and two periods of application of salt stress to plants [from sowing until 25 days later (Phase I) and from 25th to 50th day after sowing (Phase II)], with five repetitions. The main changes in gas exchange occurred in Phase II development. The salt stress reduced plant growth of sorghum in both phases of development, but this reduction was more pronounced in Phase I. The levels of organic solutes varied according to the phases of development, species and salinity. In Phase I, in both species of sorghum, there were increases in levels of Na+ and K+ and reduced Cl- by salinity, whereas in Phase II development, the levels of Na+ and K+ were reduced and Cl- extended, both in S. bicolor as in S. sudanense. In Phase I of development, only SOD in S. bicolor, and CAT in S. sudanense showed activity increases in response to salt stress. In the Phase II, no increase in the activity of antioxidant enzyme system was observed as a function of salinity in both species. In Phase I, the activity of RNase in both species was reduced by salinity, while in Phase II development, it was expanded. Plant growth of S. sudanense was slightly more affected than the S. bicolor. Sorghum species studied in this work were able to reduce the leaf ψs high concentrations of NaCl, which may have contributed to a better osmotic adjustment. In addition, under the conditions employed in the first experiment, S. bicolor appeared to have a more effective antioxidant system against the effects of salinity than S. sudanense. For the second experiment, the growth of sorghum plants was more affected when the salt stress was applied in the early stage of development. The oxidative stress caused by salinity seems to have been sufficient to stimulate the enzymatic antioxidant defense system in Phase II development in both species. Furthermore, increased activity RNase may indicate the role of this enzyme in protecting against the deleterious effects of salinity in these species of sorghum. Overall, there were no marked differences in plant tolerance between S. bicolor and S. sudanense under salinity.
Este trabalho teve por finalidade avaliar algumas variáveis fisiológicas e bioquímicas de duas espécies de sorgo forrageiro submetidas a diferentes condições de cultivo e de salinidade. Para isso, foram montados dois experimentos. No primeiro deles estudou-se tais variáveis em Sorghum bicolor e Sorghum sudanense, em função de diferentes níveis de estresse salino, enquanto no segundo, as variáveis foram estudadas em duas fases distintas de desenvolvimento das duas espécies de sorgo, visando determinar em qual delas essas espécies são mais resistentes aos efeitos deletérios da salinidade. No primeiro experimento, os tratamentos foram dispostos em esquema fatorial 2 × 5, composto por duas espécies (S. bicolor e S. sudanense) e cinco tratamentos (NaCl a 0, 25, 50, 75 e 100 mM). Nesse experimento, os parâmetros de trocas gasosas foram pouco afetados pela salinidade, em ambas as espécies. O crescimento das plantas de ambas as espécies reduziu à medida que a salinidade aumentou. O potencial osmótico (s) foliar foi fortemente reduzido pela salinidade nessas plantas, a qual aumentou significativamente a concentração de solutos orgânicos nas duas espécies de sorgo. As concentrações de Na+ e Cl- aumentaram com a salinidade em ambas as espécies. S. bicolor e S. sudanense mantiveram o teor relativo de água sob condições salinas igual ao do controle. Nas espécies de sorgo estudadas, os carboidratos solúveis e os íons K+ e Cl- foram os que mais contribuíram para o ajustamento osmótico das plantas. Nas folhas de S. bicolor, houve um aumento na atividade das peroxidases do ascorbato (APX) e do guaiacol (GPX) e uma redução na atividade da catalase (CAT), enquanto a dismutase do superóxido (SOD) não foi afetada. Em S. sudanense, à medida que foram elevadas as doses de NaCl, observou-se um aumento na atividade da GPX e da SOD. Nas raízes, apenas a SOD apresentou aumento em atividade no S. bicolor. A atividade ribonucleásica nas folhas de ambas as espécies aumentou com as doses crescentes de NaCl, enquanto que nas raízes, ela foi reduzida à medida que o estresse salino intensificou-se. No segundo experimento, os tratamentos foram arranjados em esquema fatorial 2 × 3 × 2, composto por duas espécies (S. bicolor e S. sudanense), três concentrações de sais na água de irrigação (condutividades elétricas de 0,0; 4,0 e 8,0 dS m-1) e dois períodos de aplicação do estresse salino às plantas [desde a semeadura até 25 dias depois (Fase I) e do 25º ao 50º dia após a semeadura (Fase II)], com cinco repetições. As principais alterações nas trocas gasosas ocorreram na Fase II do desenvolvimento. O estresse salino reduziu o crescimento das plantas de sorgo em ambas as fases de desenvolvimento, porém essa redução foi mais acentuada na Fase I. Os teores dos solutos orgânicos variaram em função das fases de desenvolvimento, da espécie e da salinidade. Na Fase I, em ambas as espécies de sorgo, houve acréscimos nos teores de Na+ e K+ e redução nos de Cl- pela salinidade, enquanto que, na Fase II do desenvolvimento, os teores de Na+ e K+ foram reduzidos e os de Cl-, aumentados, tanto em S. bicolor como em S. sudanense. Na Fase I do desenvolvimento, apenas a SOD, em S. bicolor, e a CAT, em S. sudanense, mostraram incrementos de atividade em resposta ao estresse salino. Já na Fase II, nenhum aumento na atividade do sistema enzimático antioxidativo foi observado em função da salinidade, nas duas espécies estudadas. Na Fase I, a atividade da RNase, em ambas as espécies, foi reduzida com a salinidade, enquanto na Fase II do desenvolvimento, ela foi aumentada. O crescimento das plantas de S. sudanense foi ligeiramente mais afetado que o de S. bicolor. As espécies de sorgo forrageiro estudadas neste trabalho foram capazes de reduzir o s foliar em concentrações elevadas de NaCl, o que pode ter contribuído para um melhor ajustamento osmótico. Além disso, nas condições empregadas no primeiro experimento, S. bicolor pareceu ter um sistema antioxidante mais eficaz contra os efeitos da salinidade do que S. sudanense. Em relação ao segundo experimento, o crescimento das plantas de sorgo forrageiro foi mais afetado quando o estresse salino foi aplicado em estádios iniciais do desenvolvimento. O estresse oxidativo causado pela salinidade parece não ter sido suficiente para estimular o sistema de defesa enzimático antioxidativo na Fase II do desenvolvimento, em ambas as espécies. Além disso, o aumento na atividade RNásica pode indicar o papel desta enzima na proteção contra os efeitos deletérios da salinidade nessas espécies de sorgo. De modo geral, não houve diferenças marcantes na tolerância das plantas de S. bicolor e S. sudanense à salinidade.

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25

Dieye, Ibrahima. "Les moisissures des grains de sorgho (Sorghum bicolor (L. ) moench. ) : étiologie et pouvoir pathogène : désinfection chimique des semences." Toulouse, INPT, 1987. http://www.theses.fr/1987INPT015A.

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Apres avoir isole et identifie les pathogenes potentiels (fusarium spp. Curvularia spp. Helminthosporium spp. Et alternaria spp. ) associes a la maladie denommee "moisissures" des grains de sorgho (sorghum bicolor (l. ) moench. ) l'auteur etudie d'une part, leur pouvoir pathogene sur plantules et sur panicules en cours de formation et d'autre part une desinfection fongicide des semences prealablement contaminees artificiellement au champ. Cette etude est avantageusement completee par une experimentation en plein champ et en chambre conditionnee d'une gamme de fongicides, permettant la mise au point d'une methode efficace de traitements de semences (application du ferbame du mancozebe, du triacetate de quazatine ou du thiabendazole)

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JABRI, AZIZ. "Contribution a la connaissance des aptitudes morphogenetiques des organes de sorgho (sorghum bicolor l. Moench) cultives in vitro." Paris 6, 1989. http://www.theses.fr/1989PA066250.

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Les organes du sporophyte du sorgho cultives in vitro montrent une grande aptitude a regenerer des plantes et revelent ainsi une totipotence. Celle-ci se presente cependant avec des degres differents selon la nature et l'age des organes. C'est ainsi que les scutellums d'embryons immatures et les axes d'inflorescences tres jeunes qui produisent directement des embryons somatiques presentent le degre le plus eleve de totipotence. Les embryons et les inflorescences plus ages ainsi que les bases de jeunes feuilles et occasionnellement le mesocotyle recouvrent une totipotence indirecte se manifestant par la formation d'abord de cal blanc compact sur lequel se differencient ensuite des embryons somatiques. Dans le cas des racines ou lorsque les organes sont plus ages le totipotence est generalement incomplete et se limite a la production de cal jaune friable uniquement capable de regenerer des structures radiculaires. Enfin les organes ayant acheve leur developpement perdent irreversiblement toute aptitude a la callogenese; un tissus mousseux produit dans ce cas temoigne du degre de totipotence le plus degrade. La dynamique de recouvrement de totipotence ainsi observee peut varier egalement en fonction du genotype. L'une des principales causes dans ce cas semble etre la presence, chez certaines varietes, de tannins dont l'oxydation in vitro rend tres difficile, voir meme impossible, toute callogenese ou organogenese. Des tentatives d'elimination de l'oxydation ont montre que la plupart des facteurs qui reduisent le brunissement du a l'oxydation sont en meme temps indispensables a l'initiation et la proliferation des cals. L'utilisation de substances anti-oxydante a permis d'obtenir une legere amelioration mais ces substances, lorsqu'elles sont efficaces, deviennent toxiques. Seules des techniques physiques comme le lavage prealable a l'ethanol, l'utilisation de papier filtre comme support de culture ou le

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Chantereau, Jacques. "Etude de l'heterosis chez le sorgho (sorghum bicolor l. Moench) par l'exploitation d'ecotypes et l'analyse de leurs divergences." Paris 11, 1993. http://www.theses.fr/1993PA112007.

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Une etude de l'heterosis a ete realisee a l'aide d'un demi-diallele d'ecotypes representatifs des races cultivees importantes de sorgho. L'analyse genetique du diallele montre une preponderance assez generale des effets d'agc sur ceux de l'asc dans l'etablissement du niveau des hybrides. Cette preponderance traduit un comportement de type plutot additif des genes impliques dans l'expression des caracteres etudies. Les effets de dominance ne sont toutefois pas negligeables. Leur role est evalue au moyen de la distance de hanson et casas. La distance de mahalanobis revele la tendance depressive qu'exerce une trop grande divergence des caracteres biometriques entre ecotypes sur l'heterosis. Les indices de distances parentales exploitant differents types de marqueurs genetiques peuvent aboutir a des correlations positives significatives avec les mesures d'heterosis. Les plus nombreuses sont obtenues a partir des marqueurs rflp. Les distances genetiques usant de marqueurs enzymatiques viennent en second. Les moins bons resultats sont obtenus avec des marqueurs morphologiques. Ce classement est lie a l'importance du nombre de marqueurs exploitables et a celle du polymorphisme revele par chaque type de marqueurs. Les indices de distances ne revelent toutefois leur valeur predictive de l'heterosis que pour les ecotypes provenant d'un meme ensemble adaptatif. Ce resultat parait du a des desequilibres intra-groupes specifiques de liaison ainsi qu'a une coherence adaptative des ecotypes d'un meme ensemble preservant leurs croisements de disfonctionnements

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Dieye, Ibrahima. "Les Moisissures des grains de Sorgho, Sorghum bicolor (L.) Moench étiologie et pouvoir pathogène, désinfection chimique des semences /." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37604554n.

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Winn, Jennifer Ann. "QTL mapping of high digestibility trait in sorghum bicolor (L.) Moench." Thesis, [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2582.

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Beyel, Volker. "Wirkung von Trockenstress auf unterschiedliche Kultivare von Sorghum bicolor." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=968544983.

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Neri-Luna, Cecilia. "The effect of arbuscular mycorrhizal fungi on water relations of sorghum (Sorghum bicolor L. cv.Tegemeo)." Thesis, University of Aberdeen, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.424983.

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In this thesis, the hypothesis was tested that AMF (Glomus mosseae, Scutellospora calospora and Gigaspora margarita), thought to differ functionally, will produce different effects on water relations when inoculated onto sorghum. To overcome inherent differences between nonmycorrhizal (NM) and mycorrhizal (M) plants, a split-root system (SRS) was devised. In this approach, the plant root system was equally divided between two compartments one of which was subsequently inoculated with AMF, allowing NM and M roots on the same plant to be compared. Initially, water loss from NM and M (inoculated with G. mosseae) compartments of the SRS was measured. Roots in the M compartment had 73% of root length colonized (RLC) by G. mosseae. The water holding capacity (WHC) of the substrate was enhanced in the M compartment, and this was maintained through the drought period. G. mosseae increased root length (RL), number of root tips, root surface area and root volume. However, there was no difference in the rate of water loss between the M and NM sides of the SRS. The next experiment examined the possibility that different species of AMF might alter water loss in sorghum plants differently. Above ground, inoculation with S. calospora produced bigger plants than the other two isolates. Below ground, %RLC also differed between isolates. There was no significant difference in total RL (adding both sides) between plants, but there were differences in the number of root tips, root surface area, root volume and root branching degree. When NM and M compartments of the SRS for each AMF isolate were contrasted, roots colonized by S. calospora and G. margarita had greater RL, number of root tips and root surface area, whereas roots colonized by G. mosseae had more root tips and a different degree of branching. Once again, G. mosseae increased the WHC of the substrate, but G. margarita did so only at the last harvest. There was no effect of S. calospora on WHC. However, there were no significant differences in water loss either per LA (with one exception) or per RL between the NM and M sides of the SRS with any AMF isolate. This leads to the conclusion that while AMF affected the WHC of the substrate used in these experiments, they did not affect rates of transpirational water loss from that substrate.

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32

Aussenac, Thierry, and Martine Goube. "Limitation de l'agressivité des champignons pathogènes par les polyphénols du sorgho (Sorghum bicolor (L. ) Moench) lors de sa germination." Toulouse, INPT, 1990. http://www.theses.fr/1990INPT005A.

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Une liaison existe entre l'equipement polyphenolique des semences de sorgho (sorghum bicolor l moench) et leur regularite de levee. Sont etudies, d'une part, le pouvoir pathogene des differents champignons responsables des accidents de levee (fusarium spp. , helminthosporium spp. , alternaria spp. Et pythium spp. ) et, d'autre part, la dynamique d'evolution des composes phenoliques du sorgho, ainsi que leur action sur la croissance mycelienne, la production et l'activite enzymatique du pathogene. Les isolements effectues demontrent la nette predominance fusarium, helminthosporium, alternaria et, dans une moindre mesure, des pythium dont l'action stimulante et/ou inhibitrice s'exprime sur la germination et la croissance de la jeune plantule. L'etude de l'evolution des polyphenols apres l'inoculation artificielle revele deux phenomenes importants: d'une part la diminution des polyphenols de la graine, d'autre part la stimulation d'une production phenolique dans les parties vegetatives de certains genotypes. La mise en evidence du caractere fongitoxique des composes phenoliques du caryopse permet de demontrer le role essentiel du degre de condensation des molecules employees. Ce travail debouche sur une experience originale de pelliculage de semence en incorporant un extrait tannique a la formulation, permettant ainsi d'evaluer l'intervention de ces molecules en reponse a l'attaque simulee d'un pathogene selectionne pour son agressivite (fusarium roseum var. Culmorum)

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DUFOUR, PHILIPPE. "Cartographie moleculaire du genome du sorgho (sorghum bicolor l. Moench) : application en selection varietale ; cartographie comparee chez les andropogonees." Paris 11, 1996. http://www.theses.fr/1996PA112251.

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Le sorgho est une cereale tres importante dans la zone intertropicale semi-aride de l'afrique et de l'asie. Dans cette etude, deux cartes genetiques du genome du sorgho ont ete etablies a partir des segregations de marqueurs rflp etudiees dans deux populations de lignees recombinantes. La cartographie a ete realisee exclusivement avec des sondes heterologues de mais et de canne a sucre. Une carte composite a ete etablie a partir des informations combinees des deux populations ; elle couvre une distance cartographique de 1095 cm. Une carte genetique consensuelle des principales etudes cartographiques du sorgho realisees a ce jour est egalement presentee. Les cartes genetiques ont ete utilisees pour identifier des regions genomiques (qtl) impliquees dans la variation de caracteres quantitatifs se rapportant au grain. Les correlations phenotypiques observees entre les caracteres ont generalement ete confirmees par des colocalisations de qtl. Nos resultats ne permettent pas d'expliquer simplement l'antagonisme observe en selection entre qualite et productivite. Cependant, ils indiquent que des genes controlant l'expression des caracteristiques de la panicule, des composantes du rendement et de la faculte germinative sont lies ou sous le controle de determinants genetiques communs. L'utilisation de sondes heterologues de mais et de canne a sucre dans la cartographie du sorgho, a permis d'initier une etude comparative des genomes des trois andropogonees. Une forte colinearite des marqueurs a ete observee dans des segments chromosomiques homeologues. La cartographie comparee a montre la nature dupliquee et remaniee du genome du mais, traduisant probablement une origine tetraploide. Nous avons observe que la syntenie peut aussi concerner les genes d'interet agronomique. Les resultats indiquent que les poacees a genomes complexes ou les especes mineures devraient beneficier des recherches menees sur des plantes modeles telles que le riz ou le sorgho

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Dobbs, Carol Johnson 1963. "Variation of adaptation of selected commercial hybrid grain sorghums (Sorghum bicolor (L.) Moench) and their two successive segregating generations to variable environments." Thesis, The University of Arizona, 1990. http://hdl.handle.net/10150/278483.

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Crop performance depends on genotype, the environment in which the crop is grown, and interaction between genotype and environment. A measure of these effects is important in determining adaptation and in recommending crop genotypes to growers. In instances where hybrid seed has been introduced into developing countries, which often traditionally save seed for the next planting, determining the adaptation of genotypes and making accurate recomendations may be difficult. This experiment evaluated 15 commercial hybrid grain sorghums (Sorghum bicolor (L.) Moench), along with their segregating F₂ and F₃ generations, for adaptation to variable moisture environments. Grain yield per entry in all tests was the main phenotypic character used to measure adaptation in environments differing in mean moisture stress. Grain yield was also the main characteristic used to observe changes through generations F₁ to F₃.There was an expected decrease in yield with decreased irrigation, and with advanced generations. A close association was observed between mean 3-year grain yield of the selected hybrids and their F₂ and F₃ progenies when grown in the same environment.

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Bekele, Wubishet Abebe [Verfasser]. "Genomics of abiotic stress responses and adaptation in sorghum (Sorghum bicolor (L.) Moench) / Wubishet Abebe Bekele." Gießen : Universitätsbibliothek, 2015. http://d-nb.info/1068921684/34.

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Mahmood, Athar [Verfasser]. "Performance of Sorghum (Sorghum bicolor L. Moench) as an energy crop for biogas production / Athar Mahmood." Gießen : Universitätsbibliothek, 2012. http://d-nb.info/1063953839/34.

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Giancotti, Paulo Roberto Fidelis [UNESP]. "Interação entre Sorgo Sacarino e plantas daninhas." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/132898.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O sorgo sacarino (Sorghum bicolor) é caracterizado por conter elevados teores de açúcares fermentescíveis em seu colmo, sendo considerado atualmente de alto potencial para compor a matriz energética nacional, ao produzir álcool durante a entressafra da cultura da cana-de-açúcar. A interferência das plantas daninhas é um dos fatores de maior importância durante a condução de uma lavoura. Uma vez que pouco tem sido estudado sobre esse tipo de sorgo, especificamente, estudos da interação entre as plantas daninhas e a cultura do sorgo sacarino são muito bem-vindas no desenvolvimento da agricultura energética. Os objetivos do trabalho foram: (I) determinar os períodos de interferência e índices fitossociológicos da comunidade infestante da cultura do sorgo sacarino; (II) analisar o desenvolvimento inicial de sorgo sacarino sob alta infestação de plantas daninhas; (III) estudar o efeito do exsudado do sorgo sacarino em outras espécies de plantas e avaliar o extrato radicular de uma potencial planta estimuladora da produção de sorgoleone pelo sorgo; (IV) avaliar o efeito supressor de restos culturais de sorgo sacarino sobre as plantas daninhas. Para o primeiro objetivo, os tratamentos consistiram de períodos crescentes da cultura em convivência e controle da comunidade infestante, em duas safras; sendo avaliada a biometria e a produção comercial do sorgo sacarino, além da determinação de índices fitossociológicos da comunidade infestante (densidade, dominância e importância relativa das espécies daninhas, além dos índices de diversidade e equitabilidade da comunidade). Em vasos, foi instalado o experimento para avaliar o terceiro objetivo, no qual híbridos de sorgo sacarino foram submetidos à presença de cinco plantas daninhas em alta densidade; sendo avaliadas as características morfofisiológicas do sorgo sacarino e a massa seca acumulada pela cultura e pelas plantas daninhas. Os estudos sobre a alelopatia foram realizados em laboratório, utilizando diferentes metodologias de química analítica, além de bioensaios avaliando a atividade de exsudados de híbridos de sorgo sacarino sobre germinabilidade e o desenvolvimento de plântulas teste e o crescimento de coleóptilo de trigo. No estudo do efeito supressor de restos culturais de sorgo sacarino, este foi comparado, no campo, com outros tipos de coberturas, e avaliada a reinfestação da comunidade infestante por meio de estudos fitossociológicos e a avaliação do banco de sementes do solo. Durante a produção de colmos de sorgo sacarino, a densidade de plantas daninhas foi o fator determinante para a importância das mesmas dentro da comunidade infestante, uma vez que o desenvolvimento e acúmulo de biomassa destas foram suprimidos pela competição estabelecida pela cultura. O sorgo sacarino se mostrou extremamente competitivo no campo, sendo que a interferência das plantas daninhas não acarretou em redução da produtividade da cultura, em duas safras. A supressão das plantas daninhas proporcionada pelos restos culturais da cultura de sorgo sacarino se equiparou a da cobertura de mucuna-cinza, suprimindo as plantas daninhas no campo por, pelo menos, quatro meses, durante a época seca. Em vasos, quatro plantas daninhas tiveram sua massa seca reduzida pela presença de sorgo sacarino, mesmo em reduzida densidade; além disso, o sorgo foi insensível à presença de três espécies daninhas presentes em alta densidade. Os bioensaios não apresentaram o esperado resultado de inibição alelopática do exsudado de sorgo sacarino sobre plantas teste. Devido ao elevado coeficiente de variação, a produção de sorgoleone pelo sorgo submetido ao extrato de A. theophrasti, não apresentou resultados conclusivos.
Sweet sorghum (Sorghum bicolor) is featured by the high level of fermentable sugars present in its stalk. The crop is currently considered of high potential to compose the national energetic system, by producing alcohol during the sugarcane off season. The weed interference is one of the most important factors during a crop management. Because not too much have been studied about sweet sorghum, studies about the interaction between weeds and sweet sorghum crop are very welcome for the development of the bioenergy nationwide. The aim of this research were: (I) determine the periods of weed interference and the phytosociological indexes of the weed community on the sweet sorghum crop; (II) analyze the initial growth of sweet sorghum under high weed infestation; (III) study the effect of the sweet sorghum root exudate in other plant species and also evaluate the root extract of an potential stimulant plant on the production of sorgoleone by sorghum; (IV) evaluate the suppressive effect of sweet sorghum crop residues on weeds. For the first objective, the treatments were composed by increasing periods of weed presence and weed absence at two crop seasons; when it was evaluated the sweet sorghum biometry and yield, besides the determination of phytosociological indexes of the weed community (the relative indexes of density, dominance and importance, and the weed community indexes of diversity and equitability). In pots, it was carried out an assay in order to evaluate the third aim, in which hybrids of sweet sorghum were submitted to the presence of five weed species in higher density. It was evaluated the morphophysiological features of sweet sorghum and the dry mass of both crop and weeds. The studies about allelopathy were carried out in laboratory, using different methods of analytical chemistry. Bioassays was carried out in order to evaluate the activity of exudates of sweet sorghum hybrids on test plants seed germinability and seedling development. In the study of the suppressor effect of sweet sorghum residues, it was compared at field with other cover crops and it was evaluated the reinfestation of the weed community by phytosociological studies and seed soil bank evaluation. During the sweet sorghum crop, the weed density was the determinant factor for the weed importance in the weed community, once the weed development and dry mass accumulation were suppressed by the competition established by the crop. The sweet sorghum showed an extremely competitive behavior on field and the interference of weeds did not cause yield loss, in two crop seasons. The weed suppression provided by the sweet sorghum crop residues was similar to the one provided by Mucuna pruriens, controlling the weeds on field for at least four months, during the dry season. In pots, four weed species had their dry mass reduced by the presence of sweet sorghum, even in lower density of the crop. Besides that, the sweet sorghum was insensitive to the presence of three weed species that were present in higher density. The bioassays didn’t show the expected result of allelopathic inhibition of sweet sorghum exudate on test plants. Due to the high coefficient of variation, the production of sorgoleone by sorghum subjected to root extract of A. theophrasti, did not show conclusive results.
FAPESP: 2012/11464-5

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Costa, Joao Paulo Nunes da. "Crescimento e Produção da Primeira Rebrota de Cultivares de Sorgo Sob Diferentes Lâminas de Irrigação." Universidade Federal Rural do Semi-Árido, 2017. http://bdtd.ufersa.edu.br:80/tede/handle/tede/769.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Sorghum is a plant indicated for the production of silage in dry regions because it presents tolerance to hydric stress and nutritional quality. Among the advantages of the culture of the sorghum it is presented the regrowth of the ratoons that allows the realization of other crops without the need to install the crop again, reducing the cost of production and the ground pressure. Due to the need to obtain information about the sorghum culture for the semi-arid region especially of new varieties, the objective of this paper is to characterize the sprout behavior of sorghum and forage sorghum cultivars in the potiguar semiarid under different irrigation slides and also to determine the irrigation blade for the sorghum crop. The experiment was carried out in the municipality of Upanema-Rn, Brazil. The trial design was a randomized complete block in a scheme of subdivided portions (4 x 5 x 2), with four replications, being four irrigation blades applied(50, 75, 100 and 125% of ETc) estimated from Kc and ETo obtained by Penman-Monteith from climate data measured in Mossoró, RN in the portion and the five cultivars (two saccharines - BRS 508, BRS 511 and three forage crops-IPA 467-4-2-B Ponta Negra) in factorial with two densities in the subplots. The spacing used was the double of 1.05 x 0.35 x 0.15 m, and the experimental plot consisted of six lines of 5 m in length. The floor area consisted of 3.0 m of the two central lines, where all the data were collected. The variables studied were: Leaf Area Index (LAI), Plant Height (m), Stem Diameter (cm) and Productivity. The data were submitted to analysis of variance (F test) and the averages were compared by the Tukey test at the 5% probability level, using the software, SAEG version 8.1. Evaluating the productivity of total fresh mass of the aerial part of resprout of five cultivars of sorghum as a function of the irrigation slides and dry mass production, it was verified that the IPA SF-15 cultivar, associated with a 100% ETc blade, along with IPA 467-4-2 and BRS Ponta Negra were more productive. The application of irrigation blade equivalent to 50% of ETc provided a reduction of only 17% of fresh biomass and 23% of dry biomass in relation to the blade (100% ETc)
O sorgo é uma planta indicada para a produção de silagem em regiões secas por apresentar tolerância ao estresse hídrico e qualidade nutricional. Entre as vantagens da cultura do sorgo, apresenta rebrota das soqueiras que possibilita a realização de outras safras sem a necessidade de se instalar a cultura novamente, reduzindo o custo de produção e a pressão sobre o solo. Diante da necessidade de se obter informações sobre a cultura do sorgo para região do semiárido principalmente de novas variedades, tem-se como objetivo deste trabalho caracterizar o comportamento da rebrota de cultivares do sorgo sacarino e forrageiro no semiárido potiguar sob diferentes lâminas. O experimento foi realizado no município de Upanema - RN, o delineamento experimental de blocos casualizados completos, em esquema de parcelas subdivididas 4 x (5 x 2), com quatro repetições, sendo quatro lâminas de irrigação aplicada (50, 75, 100 e 125% da ETc) estimada a partir dos Kc e da ETo obtida por Penman-Monteith a partir de dados climáticos medidos em Mossoró/RN, na parcela e as cinco cultivares (duas sacarinas - BRS 508 e BRS 511 e três forrageiras - IPA 467-4-2; IPA SF-15 e BRS Ponta Negra) em fatorial com duas densidades de plantio nas subparcelas. O espaçamento utilizado foi o duplo de 1,05 x 0,35 x 0,15 m, e a parcela experimental constituída de seis linhas de 5 m de comprimento. A área útil foi constituída por 3,0 m das duas linhas centrais, onde foram coletados todos os dados. As variáveis estudadas foram: Índice de Área Foliar (IAF), Altura de Plantas (m), Diâmetro de Colmo (cm) e Produtividade. Os dados foram submetidos à análise de variância (teste F) e as médias comparadas pelo teste de Tukey ao nível de 5% de probabilidade, por meio do software, SAEG versão 8.1. Avaliando-se a produtividade de massa fresca total da parte aérea da rebrota de cinco cultivares de sorgo em função das lâminas de irrigação e a produção de massa seca verificou-se que a cultivar IPA SF-15, associada a lâmina de 100% da ETC, junto com a IPA 467-4-2 e BRS Ponta Negra foram mais produtivas. Aplicação de lâmina de irrigação equivalente a 50% da ETc proporcionou redução de apenas 17% de biomassa fresca e de 23% de biomassa seca em relação a lâmina (100%ETc)
2017-07-21

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39

Junior, Carlos Bloch. "Studies on α-amylase inhibitors from seeds of Sorghum bicolor." Thesis, Durham University, 1991. http://etheses.dur.ac.uk/6283/.

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Six inhibitors (Slal, SIa2, SIa3, SIa4, SIa5 and SIa6) of α-amylase from mammalian, insect, bacterial and fungal sources were purified from seeds of Sorghum bicolor (L) Moench by saline extraction, precipitation with ammonium sulphate, affinity chromatography on Red Sepharose, preparative and analytical reverse phase HPLC on Vydac C(_18) columns. The complete primary structures of five of these inhibitors (Slal-5) were determined by automatic degradation of the intact, reduced and S-alkylated proteins and by manual DABITC/PITC microsequencing of peptides obtained from enzyme digests. The first three inhibitors consist of 47 (Slal) and 48 (SIa2, SIa3) amino acids with respective molecular weights of 5,396, 5,310. and 5384. These basic proteins (pi predictions above 8) were found to be highly homologous between themselves and with the recently isolated γ-hordothionin. γ(_1)-and γ(_2)-purothionins (Colilla et al., 1990; Mendez et al., 1990) and are, therefore, considered to be thionin-like inhibitors. Four disulphide bonds were identified and their positions determined in the sequence of Slal. It has been reported that the α-amylase inhibitory activity of thionins is due to competition for calcium ions which is the most important co-factor for this enzyme activity (Matsuura et al., 1984; Buisson et al., 1987). Calcium binding motifs have been located in the sequences of Slal, Sla2 and Sla3 and their structural significance has been investigated by molecular modelling.SIa4 and SIa5 which consist of 118 (MW 12,485) and 116 (MW 12,761) amino acids respectively are also basic polypeptides (pI predictions above 8). These proteins were found to be 35% homologous between themselves and showed significant homology (range 21-42%) with the members of the cereal superfamily. Hydrophobicity plots and secondary structure prediction results also revealed common features between these proteins and those of the cereal superfamily. Only a preliminary N-terminal sequence was obtained for Sla6 which was found to inhibit human salivary α-amylase and locust gut α-amylase.

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Hosaka, Guilherme Kenichi. "Estabelecimento de protocolo de cultura de tecidos de Sorghum bicolor." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/11/11144/tde-11112014-155455/.

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O sorgo é uma planta monocotiledônea diplóide com ciclo de vida de aproximadamente quatro meses. Apresenta grande relevância na agricultura pela sua utilização tanto para a alimentação humana e de animais quanto para a produção de biocombustíveis. Recentemente, o sorgo também surge como um forte candidato como planta modelo em estudos genômicos e fisiológicos relacionados com parede celular de gramíneas C4. Porém, para a análise da função de genes nesta espécie é essencial o estabelecimento da tecnologia de transformação genética que por sua vez depende de um eficiente método de regeneração de plantas. Nesse contexto, este trabalho teve como objetivo estabelecer um protocolo de cultura de tecidos utilizando discos de folhas e embriões imaturos como explantes, de modo a avaliar a redução do nível de oxidação na cultura in vitro pelo uso de antioxidantes e determinar as concentrações de reguladores vegetais para indução de embriogênese somática e regeneração de plantas. Em discos de folhas, os antioxidantes, PVP, ácido ascórbico e ác. cítrico foram testados na manipulação dos explantes até a inoculação em meio de cultura, porém não houve redução no nível de oxidação. Foram testados diferentes concentrações de 2,4-D para indução de calos e o uso de 1 mg L-1 e 2 mg L-1 apresentaram melhores respostas em embriogênese somática. Diferentes meios de cultura foram testados para obtenção de regeneração de plantas, mas a eficiência chegou somente a 1% de plantas a partir de discos de folhas. Em embriões imaturos, além dos antioxidantes PVP e ácido ascórbico, foram testados também os aminoácidos asparagina e prolina em meio de indução de calos. O uso de 2 g L-1 de asparagina e 3 g L-1 de prolina no meio de indução de calos e 3 mg L-1 de TDZ no meio de regeneração de plantas aumentou a eficiência de obtenção de plantas para até 15%. Assim, o uso de embriões imaturos foi considerado o explante mais promissor para a cultura de tecidos de sorgo. Devido aos altos níveis de oxidação e a baixa eficiência de regeneração de plantas em cultura de tecidos, foi testado o método de transformação genética via Agrobacterium tumefaciens conhecido como \"Floral dip\". Esta técnica não necessita da etapa de regeneração de plantas in vitro. Inicialmente, resultados promissores foram obtidos, porém há a necessidade do aprimoramento da metodologia.
Sorghum is a diploid monocot plant with a short life cycle of about 4 months. This crop is important in agriculture because it can be used for animal and human feed, and as well as source of raw material for biofuel production. Recently, sorghum also emerges as a strong candidate being a model plant on genomic and physiological studies related to cell wall in C4 grasses. Nevertheless, an efficient plant regeneration method is required for the establishment of genetic transformation technique to conduct the characterization of functional genes. In this context, the objective of this work was to establish a tissue culture protocol to evaluate the oxidation level of in vitro culture using leaf discs and immature embryos as explants, and testing different antioxidants and hormones concentrations for somatic embryogenesis and plant regeneration. In leaf discs, PVP, ascorbic acid and citric acid antioxidants were tested when manipulating the explants until their inoculation in culture media, but these factors failed to show any reduction in oxidation. In order to obtain somatic embryogenesis different concentrations of 2,4-D were tested for callus induction, 1,0 and 2,0 mg L-1 showed the best results. Several plant regeneration medium were tested however, only up to 1% of regeneration was achieved using leaf discs. In immature embryos, besides PVP and ascorbic acid antioxidants also asparagine and proline amino acids were tested in the callus induction media. The use of 2 g L-1 asparagine and 3 g L-1 proline in callus induction media and 3 mg L-1 TDZ in the regeneration media improved shoot regeneration efficiency up to 15%. Thus, the use of immature embryos was considered as a better option as explant for tissue culture of sorghum. Due to high production of oxidation and low frequency of plant regeneration in tissue culture, the genetic transformation via Agrobacterium tumefaciens known as \"Floral Dip\" method was tested. This technique does not require in vitro plant regeneration. Preliminary results were obtained, but the methodology needs to be improved.

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Bushula, Vuyiswa Sylvia. "Genetic diversity and pathogenicity of sorghum-associated Fusarium species." Diss., Kansas State University, 2017. http://hdl.handle.net/2097/35196.

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Doctor of Philosophy
Department of Plant Pathology
Christopher R. Little
Understanding the genetic structure of fungal pathogens enables the prediction of evolutionary forces that drive pathogen evolution, which assists informed decision-making regarding disease management. The genetic structure of Fusarium thapsinum and F. andiyazi, two important pathogens that cause grain mold and stalk rot of sorghum (Sorghum bicolor), are little understood. The genetic structure and pathogenicity of a F. thapsinum population from sorghum in Kansas were evaluated with amplified fragment length polymorphisms (AFLPs), vegetative compatibility groups (VCGs), sexual cross-fertility, and seedling pathogenicity. Two sympatric populations and a genetically intermediate "hybrid" group were identified in Kansas. Seedling pathogenicity of strains ranged from non-pathogenic to pathogenic, which may be partially attributable to genetic variability in the F. thapsinum populations. Genetic relatedness between populations of F. thapsinum from sorghum in Kansas, Australia, Thailand, and three African countries (Cameroon, Mali, and Uganda) were evaluated with AFLP markers and sexual crosses. Genetic diversity was high in all locations, but female fertility is very low. These results are consistent with the hypothesis that both sexual and asexual modes of reproduction are important components of the life cycle of F. thapsinum in these populations. More strains from Kansas and Africa were available for analysis than from Australia and Thailand, so the Kansas and Africa populations dominated the genetic structure observed. The two smaller populations from Australia and Thailand were more closely related to the Kansas population than they were to the African population. The three non-African populations contained information from the African population and from other, as yet unidentified, source population(s). Identifying the population(s) from which this genetic diversity originated is an important unanswered question. Stalk rot of sorghum was evaluated by inoculating stalk rot sensitive and stalk rot resistant sorghum lines with six genetically diverse F. thapsinum strains from Kansas under field and greenhouse conditions. One susceptible line (Tx7000) and two resistant lines (SC599 and BTx399) were evaluated in the field but only Tx7000 and SC599 were evaluated in the greenhouse. Disease severity was measured by major lesion length and the number of nodes crossed by the lesion. There were differences in aggressiveness amongst the F. thapsinum strains in both the greenhouse and field evaluations. This study provides the first evidence for differences in stalk rot aggressiveness amongst F. thapsinum strains and highlights the importance of challenging germplasm with well-characterized strains that represent the genetic spectrum of the entire population. The genetic diversity within F. andiyazi populations and some closely related strains was evaluated with AFLP markers. Phylogenetic and STRUCTURE analyses of the AFLP markers grouped the 81 F. andiyazi strains into three distinct clusters. The clusters were not based on the geographic origin of the strains. These results indicate the presence of at least one and possibly two undescribed sister taxa of F. andiyazi. More work is needed to further characterize these sister species of F. andiyazi and to understand their role in sorghum pathogenicity. There is genetic variation in global populations of F. thapsinum and the observed variation could be associated with variation in both seedling and adult plant pathogenicity. The study of F. andiyazi populations validated the need to properly identify and characterize Fusarium spp. associated with sorghum from different regions of the world.

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Dalcin, Joner Silveira. "Condutividade elétrica, envelhecimento acelerado e atividade enzimática em sementes de sorgo sacarino." Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/5148.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
The objective of this study was to analyze the quality of sweet sorghum seeds and their biochemical and physiological relationships by the tests of electrical conductivity, accelerated aging and activity of ezymes. Four seed lots were analyzed for each cultivar BRS 506 and F-19 separately. The physical and physiological quality were evaluated by the moisture content, weight of a thousand seeds and germination, first count of germination, length of radicle and aerial portion, dry weight, cold test and seedling emergence in the field and later were subjected to the following experiments: i: electrical conductivity mass with variations in immersion time (2, 4, 6, 8, 12 and 24 hours), temperature (20, 25 and 30 ° C), number of seeds (25 and 50), water volume (50 ml and 75); ii: Individual electrical conductivity variations in the soaking time (2, 4, 6, 8, 12 and 24 hours); iii: artificial accelerated aging using variations in temperature (41, 43 and 45 ° C) and storage time (48, 96 and 120 hours); and iiii: activity of the enzymes superoxide dismutase (SOD) and guaiacol peroxidase (POD) to root and aerial portion. The experiments were conducted in a completely randomized design and were assessed by comparison of means by the Scott-Knott test for enzymes and Tukey test for the other variables. The results obtained in electrical conductivity conclude that: a) it was possible to detect only the low vigor lot of the F-19 cultivar, especially in combinations using a temperature of 20 ° C, 75 mL and 25 seeds; b) there was no stratification of lots by the physiological quality on BRS 506 depending on the similarity between batches; c) the individual electrical conductivity test was efficient in detecting the lot of low physiological quality for both cultivars, and it can be accomplish in 24 hours in both cultivars. The results of the accelerated aging test and enzyme activity can be concluded that: a) the accelerated aging was sensitive to detect differences between the lots and their relation to physiological quality; b) at a temperature of 43 ° C and 96 hours were related with the best potential physiological quality of the lots; c) the enzyme activity was specific for each seedling body, with lower activity of SOD in roots and increased activity in the aerial portion, and POD enzyme, increased activity in the roots and lower activity in the aerial portion; d) the quality of the lots of each cultivar seeds influenced the activity of enzymes SOD and POD; e) 45 ° C and 96 hours was detrimental to the enzymes decreasing their activity.
O objetivo do presente trabalho foi analisar a qualidade das sementes de sorgo sacarino e suas relações bioquímicas e fisiológicas pelos testes de condutividade elétrica, envelhecimento acelerado e atividade das ezimas. Foram analisadas sementes de quatro lotes de cada cultivar BRS 506 e F-19 separadamente. A qualidade física e fisiológica foram avaliadas através do grau de umidade, peso de mil sementes e dos testes de germinação, primeira contagem da germinação, comprimento de radícula e parte aérea, massa seca, teste de frio e emergência de plântulas a campo e, posteriormente foram submetidas aos seguintes experimentos: i: condutividade elétrica massal com variações no tempo de embebição (2, 4, 6, 8, 12 e 24 horas), temperatura (20, 25 e 30ºC), número de sementes (25 e 50), volume de água (50 e 75 mL); ii: condutividade elétrica individual com variações no tempo de embebição (2, 4, 6, 8, 12 e 24 horas); iii: envelhecimento acelerado artificial utilizando-se variações na temperatura (41, 43 e 45ºC) e no tempo de armazenamento (48, 96 e 120 horas); e iiii: atividade das enzimas superóxido dismutase (SOD) e guaiacol peroxidase (POD) para raiz e parte aérea. Os experimentos foram conduzidos no delineamento inteiramente casualizado e foram avaliados através da comparação de médias pelo teste de Scott-Knott para as enzimas e teste de Tukey para as demais variáveis. Os resultados obtidos nos testes de condutividade elétrica pemitem concluir que: a) foi possível detectar apenas o lote de menor qualidade fisiológica da cultivar F-19, principalmente nas combinações utilizando a temperatura de 20ºC, 75 mL e 25 sementes; b) não houve estratificação dos lotes pela qualidade fisiológica na cultivar BRS 506 em função da semelhança entre os lotes; c) o teste de condutividade elétrica individual foi eficiente em detectar o lote de menor qualidade fisiológica para as duas cultivares, sendo possível realizá-lo em 24 horas nas duas cultivares. Os resultados obtidos no teste de envelhecimento acelerado e atividade das enzimas permitem concluir que: a) o envelhecimento acelerado foi sensível em detectar diferenças entre os lotes e sua relação com a qualidade fisiológica; b) a temperatura de 43ºC e 96 horas se relacionaram melhor com o potencial de qualidade fisiológica dos lotes; c) a atividade das enzimas foi específica em cada órgão da plântula, havendo menor atividade da SOD nas raízes e maior atividade na parte aérea, e na enzima POD, maior atividade nas raízes e menor atividade na parte aérea; d) a qualidade dos lotes de sementes de cada cultivar influenciou na atividade das enzimas SOD e POD; e) 45ºC e 96 horas foi prejudicial para as enzimas diminuindo a atividade.

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Biondo, Jean Cecchin. "Parâmetros qualitativos e maturação de genótipos de sorgo sacarino em Santa Maria-RS." Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/5146.

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Fundação de Amparo a Pesquisa no Estado do Rio Grande do Sul
The Brazilian ethanol production is mainly based on the sugarcane crop, however in the off-season mills plants cease processing, decreasing revenues as a result of the shortage of raw materials. It is in this scenario that fits the sweet sorghum, being able to provide quality material during the off-season sugarcane, in the summer months. The objective of this study was to evaluate the qualitative parameters and maturation curves of eleven genotypes of sweet sorghum, aiming ethanol production. Field experiment was conducted in Santa Maria-RS, in two growing seasons (2012/13 and 2013/14). The experimental design was randomized blocks with three replications and the treatments consisted of eleven genotypes, seven varieties (BRS506, BRS511, Fepagro 17, Fepagro 19, Past 81-04, Past 29-51 and Past 29-49) and four hybrids (CV007, CV147, CV568 and CV198). The quality of sweet sorghum juice was evaluated based on parameters: sucrose content (%), reducing sugars (%), purity (%), total soluble solids (°Brix), total recoverable sugar (kg t-1), fiber (%) and ethanol production (l ha-1). It was determined the maturity curve to characterize the industrial use period (IUP). The genotypes BRS506, BRS511 and CV198 showed IUP over 30 days. The BRS506 and BRS511 genotypes showed better characteristics for ethanol production.
A produção brasileira de etanol é baseada principalmente na cultura da cana-de-açúcar, porém, no período de entressafra as usinas cessam o processamento, diminuindo as receitas em decorrência da escassez de matéria-prima. É neste cenário que se encaixa o sorgo sacarino, capaz de fornecer material de qualidade durante o período de entressafra da cana, nos meses de verão. Desta forma, o objetivo do presente estudo foi avaliar os parâmetros qualitativos e as curvas de maturação de onze genótipos de sorgo sacarino durante dois anos de cultivo, visando a produção de etanol. O experimento foi conduzido em Santa Maria-RS, nos anos agrícolas de 2012/13 e 2013/14. Foi utilizado o delineamento experimental de blocos ao acaso com três repetições e os tratamentos foram compostos por onze materiais genéticos, sendo sete variedades (BRS506, BRS511, Fepagro 17, Fepagro 19, Past 81-04, Past 29-51 e Past 29-49) e quatro híbridos (CV007, CV147, CV568 e CV198). Foram avaliados os parâmetros qualitativos sacarose do caldo (%), açúcares redutores do caldo (%), pureza do caldo (%), sólidos solúveis totais (°Brix), açúcar total recuperável (kg t-1), fibra (%), rendimento de etanol (l ha-1) e também as curvas de maturação para a obtenção do período de utilização industrial (PUI). Os genótipos BRS506, BRS511 e CV198 apresentaram PUI superior a 30 dias. Os genótipos BRS506 e BRS511 apresentaram melhores características para produção de etanol.

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Mpofu, Leo Thokoza. "Evaluation of the heterotic potential of sorghum [Sorghum bicolor (L.) Moench] adapted to the southern Africa region." Thesis, Texas A&M University, 2005. http://hdl.handle.net/1969.1/4891.

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Sorghum [Sorghum bicolor (L.) Moench] production in Africa is widespread with low yields due to low inputs and the lack of sorghum hybrids. This situation has forced most of these farmers to grow maize hybrids since they are readily available in the seed market. Sorghum hybrids could be used if their potential was demonstrated. The objective of this study is to document the level of heterosis in Southern Africa sorghum germplasm. The performance of 52 F1 grain sorghum hybrids and their parental lines was evaluated in four environments. Measurements for grain yield, panicle exsertion, days to mid anthesis and plant height were analyzed to obtain estimates of high parent heterosis. High parent heterosis was observed to be 37.18% for yield, 82.77% for exsertion, -0.02% for days to mid anthesis and 23.7% for height. ICSR-939 and (87EON366*90EON328)-LD30 can be used as testers to develop more female lines for further hybrid seed production in breeding programs because they had the highest general combining ability. Protein content averaged 11.69%. ATx635 had significantly higher protein content than ATx631 (13.49% compared to 9.69%, respectively) and its hybrids had more protein than ATx631 hybrids (11.6% compared to 10.67% for ATx631). Mean heterosis for protein content was negative at -12.5%. This shows that hybrids had lower protein content than their parents since protein content is negatively correlated to grain yield (-0.35**). Starch content averaged 72.13% and ATx631 hybrids had more starch than ATx635 hybrids (73.16 compared to 72.37% respectively). Two hybrids, ATx.631/(87EON366*90EON328)-LD30 and ATx631/ ((TAM428*SV1)*CE151)-LD3 had the highest yields (5.04 t/ha and 4.93 t/ha, respectively). These hybrids also had small grains with good hardness and acceptable whiteness. They had good exsertion, flowered in good time and had acceptable plant heights. These two hybrids were compared to regional check varieties Macia and Tegemeo for all traits and they were either superior or within an acceptable range. These two hybrids are therefore recommended for release in the region. There is need therefore to start working on the various components of seed systems in the region so that seed of these two hybrids is made available to farmers who need the seed.

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Yilmaz, Kutay. "Seeding Date and Genotype Maturity Interactions on Grain Sorghum [Sorghum bicolor –(L.) Moench] Performance In North Dakota." Thesis, North Dakota State University, 2020. https://hdl.handle.net/10365/32043.

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Grain sorghum [Sorghum bicolor (L.) Moench] varieties fail to reach maturity in North Dakota’s short and cool growing season. The study objective was to evaluate seeding date and white grain sorghum genotypes. A randomized complete block design study was conducted at Carrington, Oakes, and Prosper, ND, in 2018 and 2019. Genotypes included two commercial hybrids and four open-pollinated genotypes. Reaching heading and anthesis, hybrids required more heat units (GDDs), compared with the open-pollinated genotypes. Highest grain yield was obtained from the first and second seeding dates. Earlier-maturing open-pollinated genotypes maintained yield across seeding dates, whereas yield was reduced at later dates for the longer maturity hybrids. Hybrids produced the highest number of kernels per panicle at the first seeding date with fewer seeds at each successive seeding date. Although the open-pollinated genotypes out-yielded the hybrids at later seeding dates, the risk of lodging is too great to recommend their commercialization.

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46

Alemayehu, Makonnen. "Germination and emergence salt tolerance of sorghum (Sorghum bicolor L.) as influenced by seed quality and generations." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184933.

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Artificially aged and non-aged seeds of 22 grain sorghum (Sorghum bicolor L.) F₁ hybrids and their F₂ and F₃ generations were evaluated for germination salt tolerance. Six of the hybrids, along with their F₂ and F₃ generations, were tested for emergence salt tolerance. Effects of seed production environments on germination salt tolerance were also studied using F₂ generations of 12 sorghum hybrids produced under full-season irrigation, limited irrigation, and double-cropping conditions. Germination tests were conducted in a growth chamber, on trays, while the emergence test was conducted in a greenhouse in flats filled with sand. The experiments were conducted under non-saline and saline conditions in randomized complete block designs. Artificial seed aging resulted in significant reductions in germination percentages under both non-saline and saline environments. The overall mean reduction in germination caused by seed aging was more than twice as much under salinity stress as under the non-stress conditions (48 vs. 17%), indicating differential effects of salinity on different quality seeds. Entries that appeared to be resistant to seed aging also had higher germination percentages under salinity stress. Seed production environment influenced germination performance in both non-saline and saline environments. The overall mean germination percentages of sorghum seeds produced under three different field environments were significantly different from one another. Significant differences were observed in germination and emergence percentages within F₁, F₂, and F₃ generations. Except for the F₁ entries, however, emergence index differences within the F₂ and F₃ generations were not significant. Correlations between germination and emergence percentages in the non-saline and saline treatments were generally nonsignificant. This suggests that germination and emergence responses of sorghum may vary under different salinity levels and different environments.

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Nunes, João Rodolfo Guimarães. "Potencial fisiológico de sementes de sorgo silageiro em função de diferentes seqüências de beneficiamento." Universidade Federal de Pelotas, 2008. http://repositorio.ufpel.edu.br/handle/ri/1463.

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This paper had the objective of checking the effects of three different sequence of conditioning on the qualities of seeds from silage sorghum (Sorghum bicolor L.) and to such deed, it was used FEPAGRO-RS 11, FEPAGRO-RS 12, FEPAGRO 17 e FEPAGRO 18. The treatment followed the next sequence: T1- pre cleaning; T2 pre cleaning plus three passages through cleaning; T3 pre cleaning, polishing and cleaning. The pre cleaning procedure was done by a pre-cleaning machine with a 5,0mm diameter sieve. The clean was done with an air machine and sieves, whose round holes measured 3,2 and 2,8mms. The polishing was performed by a cereal polisher machine from the brand Grimm (6 to 10sc/h). The treatments were measured through the levels of moisture, the mass of thousand seeds, purity physical analysis and germination tests, first germination count, accelerated aging, electric conductivity and tetrazolien, applied right after the conditioning and 12 months later. It as observed some differences between FEPAGRO-RS 11, FEPAGRO-RS 12, FEPAGRO 17 e FEPAGRO 18, concerning the levels of initial moisture, the mass of thousand seeds and the physiological qualities of the seeds. All the conducting treatments managed to obtain a purity quality superior to 99,0% It can be concluded that the sequence of conditioning consisted by the pre cleaning operations, polishing and cleaning, improves the visual aspect and does not damage the physiological potential of the seeds from silage sorghum.
O presente trabalho teve por objetivo verificar o efeito de três seqüências de beneficiamento sobre a qualidade de lotes de sementes de sorgo silageiro (Sorghum bicolor L.) e, para tal, utilizaram-se os cultivares FEPAGRO-RS 11, FEPAGRO-RS 12, FEPAGRO 17 e FEPAGRO 18. Os tratamentos consistiram das seguintes seqüências: T1 apenas a pré-limpeza; T2 pré-limpeza mais três passagens pela limpeza; T3 pré-limpeza, polimento e limpeza. A operação de pré-limpeza foi realizada com máquina de ar e peneiras, contendo uma peneira com orifício de 5,0mm de diâmetro. A limpeza foi efetuada na mesma máquina de ar e peneiras, cujas peneiras tinham orifícios redondos de 3,2 e 2,8mm. O polimento foi realizado com um polidor de cereais da marca Grimm (6 a 10sc/h). Os tratamentos foram avaliados através das determinações do grau de umidade, massa de mil sementes e análise de pureza e dos testes de germinação, primeira contagem da germinação, envelhecimento acelerado, condutividade elétrica e tetrazólio, aplicados logo após o beneficiamento e 12 meses depois. Observaram-se diferenças entre os cultivares, quanto ao grau de umidade inicial, massa de mil sementes e qualidade fisiológica das sementes. Todos os tratamentos de beneficiamento permitiram obter pureza física superior a 99,0%. Concluiu-se que a seqüência de beneficiamento composta pelas operações de pré-limpeza, polimento e limpeza melhora o aspecto visual e não prejudica o potencial fisiológico das sementes de sorgo silageiro.

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Teixeira, Thaís Patrícia Moreira. "Estudo da maturação e ponto de colheita em materiais de sorgo destinados à bioenergia." Universidade Federal de Viçosa, 2017. http://www.locus.ufv.br/handle/123456789/18706.

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Apesar do notório desenvolvimento do setor sucroenergético brasileiro, observa-se a ociosidade das usinas na entressafra da cana-de-açúcar (Saccharum spp.) devido à falta de matéria-prima para o processamento. Neste contexto, os sorgos sacarino e biomassa [Sorghum bicolor (L.) Moench] têm sido apontados como alternativas promissoras. O sorgo sacarino destaca-se pelos colmos suculentos ricos em açúcares diretamente fermentáveis e, o sorgo biomassa, destaca-se pela elevada produção de biomassa com altos teores de lignina. Contudo, os rendimentos de etanol do sorgo sacarino têm sido abaixo do esperado e atribui-se tal fato à definição incorreta da época de colheita. Ressalta-se que o acúmulo de açúcares no colmo ocorre principalmente a partir do florescimento, o que desencadeia a competição entre colmo e grãos (drenos preferenciais) pelos fotoassimilados. Para o sorgo biomassa, é desejável que a umidade da biomassa seja próxima a 50% quando levada à caldeira. Porém, não existem estudos que caracterizem o acúmulo de matéria seca versus a desidratação da planta. Acredita- se que, caso a planta de sorgo seja mantida à campo, além de certo estádio, para favorecer a desidratação natural, ocorrerá o consumo de matéria seca devido à redução da fotossíntese líquida decorrente do processo de senescência. Neste sentido, realizou- se um trabalho inovador e detalhado para caracterização de materiais de sorgo bioenergia visando o aproveitamento de seus potenciais produtivos. Desenvolveram- se dois experimentos independentes, cuja descrição é apresentada em dois capítulos. No primeiro capítulo, aborda-se o estudo relativo ao sorgo sacarino (cultivar BRS 511), em que se objetivou determinar o ponto de colheita do sorgo sacarino e identificar qual entrenó ou segmento de entrenós são representativos do Brix total do colmo, para auxiliar na tomada de decisão quanto à colheita. Os tratamentos constituíram-se nas diferentes épocas de amostragem da cultura conforme seu estádio fenológico, sendo os estádios de emborrachamento, florescimento, grão leitoso, grão pastoso, grão farináceo, grão duro e senescência. Quantificou-se as produtividades de massa fresca e seca e a umidade. Avaliou-se o Brix e fez-se a quantificação dos açúcares presentes no caldo. As máximas produtividades de massa fresca e seca foram registradas no estádio de grão farináceo, sendo de 124 t ha -1 e 33 t ha -1 , respectivamente. O maior Brix do caldo do colmo foi registrado entre os estádios de grão pastoso e grão farináceo, com 15 °Brix. Considerando-se os estádios correspondentes à previsão de colheita (grão pastoso ao grão duro), o Brix dos entrenós 2 e 3 não diferiram significativamente do Brix real. Conclui-se que o ponto ideal de colheita para sorgo sacarino (BRS 511) é compreendido entre os estádios de grão pastoso ao duro e os entrenós 2 e 3 devem ser a seção amostrada para avaliação do Brix. No capítulo 2, apresenta-se o estudo relativo ao sorgo biomassa, cujo objetivo foi caracterizar o comportamento da biomassa, umidade e poder calorífico superior ao longo do ciclo de crescimento e desenvolvimento do sorgo biomassa (híbrido BRS 716), visando à definição do ponto ideal de colheita. As condições experimentais (tratamentos e variáveis analisadas) foram similares às previamente descritas para o sorgo sacarino. Adicionalmente, realizou-se a análise de poder calorífico superior (PCS) e energia potencial da biomassa, ao invés da análise de Brix e açúcares realizadas no experimento anterior. A produtividade de massa seca total (PMS) aumentou a partir dos estádios iniciais e atingiu o máximo de 75,5 t ha -1 no estádio de grão farináceo, coincidindo com a menor umidade registrada e com o maior PCS. Considerando-se a PMS, umidade e o PCS, infere-se que o estádio de grão farináceo corresponde ao ponto ideal de colheita para o sorgo biomassa BRS 716. O período de colheita poderia ser escalonado entre os estádios de grão pastoso, grão farináceo e grão duro, ocorrendo ligeira redução na PMS e no PCS, permanecendo a umidade inalterada.
Despite the notorious Brazilian sugarcane chain development, industrial units have been idle during the sugarcane (Saccharum spp.) off-season due to the lack of raw material for milling. In this context, sweet and biomass sorghums [Sorghum bicolor (L.) Moench] have been considered as a promising alternative. Sweet sorghum stands out due to its juicy stems with high fermentable sugars concentration, and biomass sorghum stands out and because of its high biomass production, which exhibits large amount of lignin. However, sweet sorghum ethanol yields have been lower than expected by sugarcane industries, what can be attributed to the incorrect determination of the ideal harvest time. It is worth noting that the stem sugar accumulation occurs, mainly, after the plant flowering, what unleashes the competition between stem and grains (preferential sinks) for photosynthates. For biomass sorghum, it is desirable a biomass humidity close to 50% when it is taken to the boiler. However, there are not researches that characterize dry matter accumulation versus plant dehydration. It is assumed that if the plant remains at the field, after certain time, intending to favor the natural dehydration, it can result in dry matter consumption because of net photosynthesis decrease due to senescence process. In this regard, it was carried out an innovative and detailed work to characterize bioenergy sorghum materials aiming to harness their productive potential. It was developed two independent experiments, whose description is presented in two chapters. In the first chapter, it is studied the sweet sorghum (cultivar BRS 511), aiming to determine the ideal harvest time for sweet sorghum and identify which internode or segment of internodes better represents Brix of the stem juice. The treatments consisted in the sweet sorghum phenological stages, which were pre-flowering, flowering, milk dough, soft dough, mealy dough, hard dough and senescence. Were evaluated fresh (FBY) and dry biomass (DBY) yields and humidity. Brix was evaluated and sugar content in the stem juice was quantified. The greater fresh and dry matter yields were recorded in the mealy dough stage, which were 124 t ha -1 e 33 t ha -1 , respectively. The highest Brix of stem juice was registered between the soft and mealy dough stages, with 15 °Brix. Analyzing only the soft, mealy and hard dough stages (harvest prediction), Brix of the internodes 2 and 3 had not significantly differed from the stem real Brix. The sweet sorghum BRS 511 harvest time is comprehended between the soft to hard dough stages and the in field-Brix sampling should be done at the internodes 2 and 3. In the chapter 2, it is presented a study related to biomass sorghum, which intended to characterize biomass, humidity, higher heating value and potential biomass energy during the growing and developing cycles of biomass sorghum (hybrid BRS 716). The aim was to define the ideal harvest time that maximizes the industrial yield at the bioelectricity cogeneration. The experimental conditions (treatments and analyzed variables) were similar to the ones described for sweet sorghum. Additionally, higher heating value (HHV) and potential biomass energy were quantified instead of Brix and sugar analysis. Dry biomass yield (DBY) had increased from the early stages, reaching the maximum of 75.5 t ha -1 at the mealy dough stage, coinciding with the lowest humidity content (67%) and the higher heating value. After the mealy dough stage, dry matter had decreased. Considering the DBY, HHV and humidity, it is inferred that mealy dough stage corresponds to the ideal harvest time for biomass sorghum BRS 716. The harvest gap could be staggered between the soft dough, mealy dough and hard dough stages, leading to slightly decreases in the DBY and HHV, with no changes in humidity percentage.
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49

Santana, Maria Gabrielle Sousa de. "Efect of sewage wastewater reuse of the parameters of growth and nutrition sorgo." Universidade Federal do CearÃ, 2015. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=16322.

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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
The wastewater reuse for irrigation crops has many ecological and economic advantages, for example: nutrients recycling, reducing pollution, fertilizer and water economy. Therefore, the reuse of wastewater is an alternative to regions with water deficit, especially in urban and industrial areas. Sorghum is an important crop produced by family farmers in the semiarid region and used in animal feed. Produced under rainfed conditions, the use of irrigation becomes an alternative to stability in production. The research was conducted in EstaÃÃo MeteorolÃgica do Centro de CiÃncias AgrÃrias da Universidade Federal do CearÃ. The effluent used was collected in EstaÃÃo de Tratamento de Esgotos do Campus do Pici (ETE-PICI) da Universidade Federal do CearÃ (UFC), which receives wastewater with sewage characteristics. 10 treatments were used in a completely randomized design with 4 replications. Where: T1 supply water without chemical fertilizers; T2 supply water with 25% of recommended mineral fertilization; T3 supply water with 50% of recommended mineral fertilization; T4 supply water with 75% of recommended mineral fertilization; T5 supply water with 100% of recommended mineral fertilization T6- effluent water without chemical fertilizers; T7- effluent water with 25% of recommended mineral fertilization; T8 effluent water with 50% of recommended mineral fertilization; T9- effluent water with 75% of recommended mineral fertilizer and T10 effluent water with 100% of recommended mineral fertilization. The plant height, stem diameter, number of leaves at 20 days, showed no variation in type of water applied. However, the variables showed significant difference related to the doses of N, P and K. The variables analyzed (Plant height, number of leaves, leaf area, stem diameter) at 40 days after sowing, had significant difference only for the N levels, P and K. The nutrients P and S showed statistical differences in the interaction. The nutrients K and Ca obtained significant results at 1% over the interaction. The nitrogen contents showed a significant difference as the nitrogen rates, P and K, but did not fit any regression model. The treated sewage effluent can be used for irrigation of crops provided a controlled and well managed.
A reutilizaÃÃo de Ãguas residuÃrias na irrigaÃÃo apresenta incontÃveis vantagens ecolÃgicas e econÃmicas, dentre elas estÃo: a reciclagem dos nutrientes, reduÃÃo da poluiÃÃo, economia de fertilizantes e Ãgua. Portanto, o reÃso de efluente domÃstico se mostra como uma alternativa para regiÃes com dÃficit hÃdrico, principalmente em zonas urbanas e industriais. O sorgo Ã uma cultura relevante produzida pela agricultura familiar na regiÃo semiÃrida e usada na alimentaÃÃo animal. Produzido em condiÃÃes de sequeiro o uso da irrigaÃÃo torna-se uma alternativa para estabilidade na produÃÃo. A pesquisa foi realizada na EstaÃÃo MeteorolÃgica do Centro de CiÃncias AgrÃrias da Universidade Federal do CearÃ. O efluente utilizado no estudo foi coletado na EstaÃÃo de Tratamento de Esgotos do Campus do Pici (ETE-PICI) da Universidade Federal do CearÃ (UFC), que recebe Ãguas residuÃrias com caracterÃsticas de esgoto domÃstico. Foram utilizados 10 tratamentos em delineamento inteiramente casualizado com 4 repetiÃÃes. Sendo: T1- Ãgua de abastecimento sem adubaÃÃo mineral; T2- Ãgua de abastecimento com 25 % da adubaÃÃo mineral recomendada; T3 - Ãgua de abastecimento com 50% da adubaÃÃo mineral recomendada T4- Ãgua de abastecimento com 75% da adubaÃÃo mineral recomendada; T5- Ãgua de abastecimento com 100% da adubaÃÃo mineral recomendada T6- Ãgua de efluente sem adubaÃÃo mineral; T7- Ãgua de efluente com 25% da adubaÃÃo mineral recomendada; T8- Ãgua de efluente com 50% da adubaÃÃo mineral recomendada; T9- Ãgua de efluente com 75% da adubaÃÃo mineral recomendada e T10- Ãgua de efluente com 100% da adubaÃÃo mineral recomendada. A altura das plantas, diÃmetro do colmo, nÃmero de folhas aos 20 dias nÃo apresentaram variaÃÃo em relaÃÃo ao tipo de Ãgua aplicado. No entanto, as variÃveis analisadas mostraram diferenÃa significativa apenas quanto Ãs doses de N, P e K aplicadas. As variÃveis analisadas (Altura das plantas, nÃmero de folhas, Ãrea foliar, diÃmetro do colmo) aos 40 dias apÃs a semeadura obtiveram diferenÃa significativa somente quanto Ãs doses de N, P e K aplicadas. Os nutrientes P e S mostraram diferenÃa significativa a 5% com relaÃÃo a interaÃÃo. Os nutrientes K e Ca obtiveram resultados significativos a 1% com relaÃÃo as interaÃÃo. Os teores de nitrogÃnio apresentaram diferenÃa significativa a 5% de significÃncia quanto Ãs doses de N, P e K aplicadas, mas nÃo se adequaram a nenhum modelo de regressÃo. O efluente de esgoto tratado pode ser utilizado na irrigaÃÃo das culturas desde que de forma controlada e bem manejada.

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50

Raditapole, Moorosi Vernet 1950. "Evaluation of selected grain sorghum hybrids (Sorghum bicolor (L.) Moench) and their three successive segregating generations in three different environments." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276880.

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The introduction of hybrid seed in developing countries may be in conflict with the tradition of saving seed for the next planting. This study evaluates 15 sorghum (Sorghum bicolor (L.) Moench) hybrids and their three successive generations in three environments. Under optimum conditions for all 15 genotypes segregating generations yielded as well as the F1 generation. Under moisture stress and late planting, the F2 generation showed inbreeding depression for yield and kernels per panicle. Height, panicle length and test weight were reduced and flowering was hastened for all segregating generations. Kernel weight was not affected by segregation. This study indicates that under optimal conditions it is possible to find a line among segregating generations of sorghum that is superior to its F1 hybrid.

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