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Brown, Brian Wayne. "Interactive versus non-interactive platforms for teaching plant morphology." Auburn, Ala., 2005. http://repo.lib.auburn.edu/2005%20Fall/Thesis/BROWN_BRIAN_48.pdf.
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Parmar, C. T. "The morphology of plant names in the Celtic languages." Thesis, Queen's University Belfast, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.419516.
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van, Blerk Justin. "Sexual dimorphism in the genus Leucadendron : Morphology and plant hydraulics." Bachelor's thesis, University of Cape Town, 2013. http://hdl.handle.net/11427/14014.
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The genus, Leucadendron, of the Cape Proteaceae family, is made up of over 70 dioecious species that vary in their degree of sexual dimorphism. Males are generally more highly ramified (branched) with smaller leaves compared to corresponding females. It has been hypothesised that sexual dimorphism in Leucadendrons is linked to serotiny (a fire-adapted reproductive strategy), where highly serotinous females may incur extra resource costs in order to keep their transpiring cones alive between fires. This hypothesis predicts that the female morphology might be associated with more efficient resource acquisition compared to males in order to support their greater resource requirements. Another hypothesis suggests that selection for greater floral display in males has lead to a higher degree of ramification as male cones are borne terminally on branches. This highly branched morphology may be associated with subsequent physiological costs. The idea that different male and female morphologies might be associated with different physiological costs or benefits was tested in this experiment with a focus on plant hydraulics. Hydraulic supply is known to affect photosynthetic capacity and maximum assimilation rate. Using a specially designed vacuum chamber, leaf-specific and xylem-specific hydraulic conductance was measured in males and females of the highly dimorphic Leucadendron rubrum and non/marginally dimorphic Leucadendron daphnoides. Using microscopic imagery, xylem anatomy was analysed in an attempt to explain the hydraulic conductance results.
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Li, Zhuo. "Bio-based composites that mimic the plant cell wall." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/32088.
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Nature creates high performance materials under modest conditions, i.e., neutral pH and ambient temperature and pressure. One of the most significant materials is the plant cell wall. The plant cell wall is a composite of oriented cellulose microfibrils reinforcing a lignin/hemicellulose matrix. In principle, the plant cell wall composite is designed much like a synthetic fiber-reinforced polymer composite. Unlike synthetic composites, the plant cell wall has an excellent combination of high modulus, strength, toughness and low density that originates in the optimal interactions between the biopolymers. Therefore, to produce high performance composites, a unique route may be to mimic a biological system like the plant cell wall. The present work focuses on understanding the thermodynamics of biopolymer assembly to exploit the process in vitro.
In our system, we use an already polymerized nanocellulose template and polymerize phenolic monomers on the template using a peroxidase enzyme. In the first part, we have polymerized phenol using horseradish peroxidase (HRP) in the presence of TEMPO-oxidized nanocellulose. Similar to native plant cell wall structures, the polyphenol-nanocellulose composite had intimate mixing of polyphenol and cellulose at the nanoscale with the presence of cellulose promoting a uniquely organized structure. The obtained composite material showed synergy that enhanced the thermal stability, hydrophobicity, and possibly mechanical properties.
In the second part, monolignol coniferyl alcohol was polymerized in the presence of nanocellulose by the same procedure. A comparison between the polyphenol composite and poly(coniferyl alcohol) (PCA) composite revealed that the propanyl substitution imparted flexibility to the PCA molecules so that they could bend and form a hollow globule structure to envelope nanocellulose inside. Polyphenol could not do this because of its rigidity.Master of Science
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Levy, Foster, and James T. Donaldson. "Morphology, Geographic Distribution, and Conservation of the Southern Appalachian Endemic." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etsu-works/5450.
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Taxonomic recognition of Solidago lancifolia (Torrey & A. Gray) Chapman and diagnostic characters used for identification have vacillated among floras and treatments. Fieldwork greatly expanded the specimen base in US herbaria, extended the known range in Tennessee, and identified new occurrences in North Carolina and Virginia. A morphometric analysis of herbarium specimens identified qualitative and quantitative characters unambiguously diagnostic for S. lancifolia. These included the presence of glands on the phyllaries; long, wide-diameter rhizomes; thick stems; and a long pappus on disk florets. Using these characters, an analysis of herbarium specimens corrected widespread misidentifications and showed that S. lancifolia is strictly endemic to a 12-county region encompassing the high elevations (> 1,400 m) in the mountains of southwestern Virginia, northwestern North Carolina, and northeastern Tennessee. Based on the narrow geographic range and small population sizes, prior uncertainty of the taxonomic validity and geographic range of S. lancifolia has been resolved. Consequently, for North Carolina and Virginia, the recommendation is for an upgrade in the conservation status to “Endangered” with a state rank of “S1.” Moreover, the narrow geographic range and small number of populations are consistent with a global rank of “G2” and consideration as a federal Species of Concern.
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Costa, Julia Yamagishi. "Citotaxonia e aspectos evolutivos de especies de Hoffmannsegella H.G.Jones (Orchidaceae)." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/314944.
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Orientador : Eliana Regina Forni-MartinsTese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Dentro da família Orchidaceae, composta por cerca de 25.000 espécies, o gênero Hoffmannseggella (antiga seção Parviflorae do gênero Laelia Lindl.) é composto por espécies rupícolas, endêmicas da Cadeia do Espinhaço/MG. Estudos sugerem uma evolução rápida para o gênero, com a transição do hábito epifítico para o rupícola, mudança de polinizadores e eventos de hibridização e poliploidia como os principais mecanismos evolutivos envolvidos na origem das espécies de Hoffmannseggella. Estudos cromossômicos prévios haviam sugerido o número básico de x=20 para o gênero, com alta incidência de poliplóides. No presente trabalho, foram obtidas contagens cromossômicas para dez espécies: H. angereri n=20/2n=40, H. bradei n=20-21/2n=40, H. briegeri 2n=80, H. caulescens 2n=80, H. cinnabarina 2n=40, H. crispata n=20, H. fournieri n=20/2n=40, H. liliputana 2n=40/60, H. rupestris n=40/2n=80 e 2n=40 e H. viridiflora 2n=44. Foi observada aneussomatia em células de meristema radicular em H. briegeri (2n=80) e H. rupestris (2n=80), ocorrência de citótipos em H. rupestris (2n=40/80) e anormalidades meióticas em várias espécies, com presença de monovalentes, disjunção adiantada de bivalentes e possíveis tetravalentes nas espécies poliplóides. Por ocorrerem em sincronopatria, apresentarem alta similaridade morfológica e pelas características cromossômicas, é provável que H. viridiflora tenha se originado por aneuploidia a partir de H. bradei. Através dos procedimentos de bandamentos C, CMA/DA/DAPI e DAPI/AMD, foi possível observar grandes diferenças entre os cariótipos das espécies H. angereri, H. bradei, H. briegeri, H. caulescens, H. fournieri, H. liliputana e H. rupestris. Em geral, as espécies apresentaram grande número de bandas C (predominantemente centroméricas e subteloméricas), poucas bandas CMA/DA+ (subteloméricas), e grande variação no número de bandas DAPI/AMD+ (predominantemente teloméricas). Apenas H. bradei apresentou somente duas bandas heterocromáticas, uma CMA/DA+ DA/DAPI- e uma DAPI/AMD+ e H. briegeri apresentou polimorfismo para bandas CMA/DA/DAPI. Com relação aos sítios 45S de DNAr, os resultados foram uniformes, sendo que as espécies diplóides, com 2n=40, apresentaram dois sítios, enquanto as espécies poliplóides, com 2n=80, apresentaram 4 sítios
Abstract: Inside Orchidaceae, composed of almost 25,000 species, Hoffmannseggella H.G.Jones (previous genus Laelia Lindl., section Parviflorae) is characterized by rupiculous species, endemic to the Espinhaço Range/ MG. Previous studies suggested an explosive evolution of the genus, with transition from epiphytic to rupiculous habitat, changes on pollinator specificity and events of hibridization and polyploidy as the main evolutionary mechanisms that originated Hoffmannseggella species. Chromosome data from literature suggested the base number of x=20 for the genus, with high incidence of polyploids. The present work presents chromosome counts for ten species: H. Angereri n=20/2n=40, H. bradei n=20-21/2n=40, H. briegeri 2n=80, H. caulescens 2n=80, H. cinnabarina 2n=40, H. crispata n=20, H. fournieri n=20/2n=40, H. liliputana 2n=40/60, H. rupestris n=40/2n=80 and 2n=40 and H. viridiflora 2n=44. We observed aneussomaty on root meristematic cells of H. briegeri (2n=80) and H. rupestris (2n=80), two distinct cytotypes of H. rupestris (2n=40 and 2n=80) and meiotic abnormalities in several species, like monovalents, early disjunction of bivalents and putative tetravalents on polyploid species. Because they are found sinchronopatric, with high morphological and chromosomal similarity, we suggest that H. viridiflora (2n=44) is an aneuploid derived from H. bradei (2n=40). With C, CMA/DA/DAPI and DAPI/AMD banding techniques, we observed great differences among H. angereri, H. bradei, H. briegeri, H. caulescens, H. fournieri, H. liliputana e H. rupestris. With exception of H. bradei, that presented only two heterochromatic, one CMA/DA+ DA/DAPI- and one DAPI/AMD+ bands, all species presented a high number of C-bands (mainly centromeric and subtelomeric), few CMA/DA+ bands (subtelomeric), and great numeric differences of DAPI/AMD+ bands (mainly telomeric). We also observed, in H. briegeri, a polymorphism of CMA/DA/DAPI bands. The hybridization sites of 45S rDNA were uniform among species, with diploid species (2n=40) presenting two hybridization signals and polyploid species (2n=80) presenting four signals
Doutorado
Doutor em Biologia Vegetal
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Sampson, Dennis Archie. "An assessment of the evolutionary stability of distyly in Hedyotis caerulea (Rubiaceae)." Cleveland State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=csu1296756691.
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Ahmad, Nariman Salih. "Genetic analysis of plant morphology in bambara groundnut (Vigna subterranea (L.) Verdc.)." Thesis, University of Nottingham, 2013. http://eprints.nottingham.ac.uk/13150/.
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Bambara groundnut (Vigna subterranea (L.) Verdc.) is an important underutilised legume crop, grown mainly by female subsistence farmers in Africa under traditional low input agricultural systems. Bambara groundnut is known as being of high nutritional value, as an atmospheric nitrogen fixer and to possess high levels of drought, pest and disease tolerance. Bambara groundnut is a predominantly self-pollinated crop and is grown as locally adapted landraces. These are expected to exist as non-identical inbred lines and are generally low yielding. Strategies involving genetic analysis of this species could provide important data for breeding programmes that could enhance food security in Africa. A set of 124 SSR primers designed from different library sources were tested to screen a ‘narrow’ genetic cross (F3) and a ‘wide’ genetic cross (F2) . The former is a cross between domesticated landraces (DipC and Tiga necaru) while the latter is a cross between a domesticated landrace and a wild ancestor (DipC and VSSP11). Residual heterozygosity in the F3 ‘narrow’ cross was confirmed to be around 25% based on 33 polymorphic SSR primers, consistent with an F3 population. A ‘narrow’ cross linkage map was constructed for the first time in bambara groundnut using 269 polymorphic markers (236 DArT and 33 SSR). The map consisted of 238 markers in 21 linkage groups of two or more linked markers, totalling 608.1cM and covering a predicted 54% of the bambara groundnut genome, although the high marker-marker linkage (at 89%) suggests a more comprehensive coverage. QTL analysis was carried out for 73 bulked lines of an F3 population and plants were evaluated for traits in a controlled glasshouse suite and a field trial in Indonesia. Data from single plant analysis of the F2 generation of this cross grown in a controlled environment glasshouse was also used. Most of the QTLs detected were clustered on linkage groups 1, 4 and 12. Major QTLs for internode length and biomass dry weight were detected on LG4 and LG1, respectively, for the FutureCrop glasshouse and field datasets. The highest LOD score of 9.7 was detected for peduncle length and was located within the confidence interval for a QTL for internode length locus. Marker locus bgPabg-596774 was detected to be associated with QTL for six traits; node no./plant, pod no/plant, pod weight, seed no./plant, seed yield and biomass dry weight, on LG1 within one LOD score of confidential interval, potentially suggesting pleiotropic effects of a more limited number (or even one) gene(s). One hundred and fifty-nine additional markers (136 DArT and 23 SSR) were used to improve the existing partial ‘wide’ map (141 AFLP, 1 SSR) constructed in an F2 population of 98 plants. A total of 194 markers were assigned to 20 linkage groups spanning a total of 901 cM. The linkage map derived from the ‘wide’ cross (DipC x VSSP11) had an expected genome coverage of 79.6%. An attempt to combine both maps through 32 common markers allowed a common QTL for days to emergence to be detected in both populations in close association with the common DArT markers 601384 and 601748. The main segregating traits were found to be plant spread, internode length, growth habit, peduncle length, pod weight, seed yield and biomass dry weight. Detecting the same QTL positions for a number of traits, suggested that common underlying genes might be responsible. The QTL-DNA marker associations developed in this study could be used practically for MAS in a future breeding program of this crop.
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Taylor, J. B. "Aspects of the dynamic morphology and branching patterns of rhizomatous plants with special reference to Iris pseudacorus L. and Polygonatum x hybridum Bruegger." Thesis, Bangor University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233696.
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Sherman, JoAnn Davis 1955. "Chromosome morphology, number and behavior of some Arizona Plantago species." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276649.
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Mitosis and meiosis of five Plantago species were analyzed. Plantago argyrea, P. patagonica and P. wrightiana contain 2n = 20 chromosomes and P. rhodosperma and P. virginica 2n = 24 chromosomes. Similar modes of evolution of the karyotypes of the 2n = 20 species are suggested. All species are presumed to be tetraploid, arising from 2n = 10 and 2n = 12 ancestors. Structural changes in the karyotype of 2n = 12 species could produce one or more large chromosomes resulting in a decrease in chromosomes from 6 to 5. Consequently, chromosome lengths in 2n = 10 and derived 2n = 20 species could be increased by addition of repetitive DNA along the length of each chromosome to maintain chromosome field. Chromosomes of 2n = 24 species are more symmetrical and presumably more primitive than the 2n = 20 species. Chiasma frequencies in meiotic cells of all five species are similar. This suggests that the majority of changes DNA content are in repetitive DNA.
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Teberobsky, Debora Yurman. "Aphis fabae (Scopoli) subspecies their host plant utilization, endosymbiosis and taxonomy (Homoptera: Aphididae)." Thesis, University of York, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245896.
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Smillie, Ian R. A. "Analysis of leaf morphology and photosynthesis in deletion mutants of rice (Oryza sativa L.)." Thesis, University of Nottingham, 2012. http://eprints.nottingham.ac.uk/12569/.
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As a plant operating the C3 photosynthetic pathway and commonly grown under tropical conditions of high light intensity and temperature, rice (Oryza sativa) displays high levels of photorespiration, to the detriment of photosynthetic efficiency. For this reason it is thought that improvements to net photosynthesis via an increased photosynthetic efficiency could provide significant gains in terms of grain yield. There is great interest in 1. Introducing CO2 concentrating mechanisms into C3 crop plants such as the C4 photosynthetic pathway in order to facilitate enhanced photosynthetic efficiency. This requires an understanding of C3 and C4 leaf development and establishing whether there is sufficient plasticity in the rice genome to produce plants with C4-like properties. 2. Improving existing C3 photosynthesis by means of increasing leaf thickness, vein density and investigation of the impacts of mesophyll cell size. It is in this context that a forward screen of approximately 100 mutant lines of the indica rice variety IR64 was developed at Nottingham to search for relevant changes in leaf morphology. Mutant seed produced using chemical mutagenesis (diepoxybutane and ethylmethanesulfonate) and irradiation (gamma and fast neutron) was supplied by the International Rice Research Institute (IRRI) in the Philippines. A rapid low resolution screen was devised using light microscopy of fresh, untreated hand cut leaf sections of plants at the leaf six stage. Seven mutant lines were identified as showing altered leaf morphologies and were termed alm mutants. alm1, alm5 and alm6 displayed a reduced interveinal distance between neighbouring veins, a common feature of C4 plants with Kranz anatomy, whilst alm1 and alm5 also displayed a reduction in the size of minor veins. alm3 and alm4 produced significantly thicker leaves than wild type plants, whilst the leaves of alm7 were significantly thinner. A detailed anatomical characterisation of leaf structure revealed that alm3, alm4 and alm5 plants all displayed a significant reduction in the size of mesophyll cells and that for all the mutant lines, the distance between veins was strongly correlated with mesophyll cell size rather than the number of mesophyll cells spanning the interveinal regions. Physiological properties of the alm lines were investigated using infra-red gas analysis (IRGA) measurements of gas exchange and chlorophyll fluorescence. It was shown that none of the mutant lines displayed an increase in photosynthetic capacity when compared to wild type plants, even in lines which were shown to possess what was thought to be a favourable leaf anatomy, quite possibly a result of widespread effects of the mutation process. The alm1 line was shown to display interesting physiological responses, with almost no transpiration and a severely reduced photosynthetic capacity, yet functioning stomata and an unimpaired stomatal conductance. In conclusion, the future success of photosynthetic improvement in rice will rely on the screen of much larger numbers of mutant lines of rice and C4 plants in order to identify the genes determining key conserved morphological features such as interveinal cell number, cell size and the degree to which rice mesophyll cells are lobed.
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Ravetta, Damián Andres. "Plant morphology and gas exchange in Hesperaloe: Influence on its adaptation for cultivation." Diss., The University of Arizona, 1994. http://hdl.handle.net/10150/186643.
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The working hypothesis for this dissertation was that the contrasting plant architecture, and the distinct native environments of Hesperaloe funifera and H. nocturna should be reflected in differences in their eco-physiological responses, and that these, in turn, would determine these species' adaptability limits and productivity under cultivation. The objective of this dissertation project was to evaluate plant morphological characteristics and their effect on physiological processes, and how environmental factors interact with these processes in H. funifera and H. nocturna. Common to both Hesperaloe funifera and H. nocturna is the possession of constitutive crassulacean acid metabolism (CAM). The major implication of CAM is a prominent water use efficiency (WUE). Although instantaneous net CO₂ uptake rates of both Hesperaloe funifera and H. nocturna are low when compared with C₃ plants, integrated 24-hr net CO₂ uptake rates are within the lower range of C₃ species. Because there is a relatively large range of conditions in which photosynthesis occurs (i.e., both Hesperaloe species have a long growing season), net CO₂ uptake in Hesperaloe integrated throughout the year may reach or surpass that of C₃ crops. Daily integrated CO₂ uptake during late fall, winter and early spring were similar in Hesperaloe funifera and H. nocturna. A major peak in CO₂ uptake was found during the fall for H. funifera but not for H. nocturna. Also, no reduction in integrated CO₂ uptake was found in H. nocturna during the summer months, while H. funifera showed a considerable reduction in CO₂ uptake during this season. The increase in photosynthetic activity in H. nocturna coincided with the emergence of the inflorescence. Contrastingly, flowering did not appear to increase net CO₂ uptake in H. funifera. In this species a flush of new leaf production (increased sink demand) coincides with the observed increase in photosynthesis during the fall. The late fall peak of CO₂ uptake found in H. funifera could also be caused by a photoperiodic stimulation of CO₂ uptake. Significant differences in WUE between the two Hesperaloe species were found. These differences were, at least, partially explained by contrasting plant architecture and differences in leaf morphology.
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Frank, Brian James. "Corn grain yield and plant characteristics in two water environments." Thesis, Manhattan, Kan. : Kansas State University, 2010. http://hdl.handle.net/2097/3280.
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Tepe, Eric J. "Phylogeny, morphology, and the evolution of ant-plant associations in Piper section Macrostachys (Pipereceae)." Oxford, Ohio : Miami University, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=miami1133534289.
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Oagile, Otsoseng. "African yam bean : morphology, clonal propagation and nitrogen fixation." Thesis, University of Nottingham, 2005. http://eprints.nottingham.ac.uk/12946/.
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Morphological and growth observations made on landraces of African yam bean (AYB) used in this study confirm that this species is the most morphologically variable in the genus (Potter, 1992). Morphological characters such as seed colour, stem colour, internode length, leaf size and number of leaves per plant were found to vary between landraces. Growth and development was controlled by both genotype and environment. Flowering was observed only when plants were grown at 25°C, rather than at 30°C, with a 12 h photoperiod. Tuber formation occurred only in AYBS and not in other landraces. Growth rates differed between landraces and between environments with plants grown in the soil displaying faster growth than those grown in pots. The response to the environment (pot and soil experiment) differed between landraces, i.e. AYB1 performed better than AYB2 in the pot experiment, whereas it was surpassed by AYB2 in the soil experiment. Clonal propagation protocols were developed using nodal explants/propagules to reproduce material with a high level of genetic uniformity from existing shoot meristems. Clonal propagation was investigated using macro (leafy stem cuttings) and micro (in vitro propagation from nodal stem segments) approaches. Axenic shoot cultures have been achieved from stem nodal segments sterilised with 10% "Domestos" bleach and grown in MS-based medium fortified with cytokinins. Amongst the cytokinins used, BAP (6-benzylaminopurine) was found to be more suitable than TDZ (N-phenyl-N'-1,2,3thidiazol-5-ylurea) and 2iP (6-(y, y-dimethylallylamino)purine) at both culture establishment and shoot multiplication stages, although optimisation of the protocol for shoot multiplication requires further study. There was persistent callus proliferation at both the establishment/initiation of cultures and the multiplication stage and the use of other plant growth regulators, such as GA3 (Gibberellic acid) and TIBA (2,3,5-triiodobenzoic acid), known to counter callus growth in cultures, did not give positive results. Although in vitro adventitious root formation was erratic, some shoots were able to root when exposed to auxins (IBA [indole-3-butyric acid] and NAA [αnaphthaleneacetic acid]) and were established in compost. IBA was preferable to NAA, as it induced more root formation. Overall, AYB cuttings produced adventitious roots relatively easily with or without auxins. Auxins at low concentrations induced rapid formation of roots in high numbers. Unlike in vitro rooting, adventitious rooting of cuttings was as high as 100% without any auxin treatment, suggesting a possibility of other factors involved in the rooting process in vitro. A cheap source of nitrogen for AYB is in the form of biological nitrogen fixation. AYB nodulated profusely with strains of both a slow growing Bradyrhizobium sp. and a fast growing Rhizobium sp., plants forming nitrogen fixing nodules with strains ORS302, CP279 and NGR234. Nitrogen fixed from the atmosphere accounted for 79-98% of the plant nitrogen and supported plant growth by an increase of up-to 1547% of dry matter in shoots.
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Miller, Steven L. "Basidiosporogenesis and developmental anatomy of spore release in the Russulales: a systematic interpretation." Diss., Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/53574.
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Morphologically and anatomically the Russulales (Basidiomycetes) are a homogeneous group of higher fungi, which contains both ballistosporic and statismosporic, agaricoid and gasteroid taxa. Spore symmetry and ability to forcibly discharge spores are therefore fundamental systematic characteristics in the Russulales. Ballistosporic and statismosporic basidiosporogenesis however, has not been critically compared. Early and late basidiosporogenesis, spore-wall tegumentation, and differentiation of the hilar appendix were ultrastructurally characterized in species selected from eight genera of agaricoid and gasteroid Russulales including: Russula, Lactarius, Macowanites, Arcangeliella, Elasmomyces, Gymnomyces, Martellia, and Zelleromyces. Six spore-wall layers are present in developing spores in all genera. Two wall layers are associated with an evanescent pellicle and four wall layers are derived from the sterigma and young spore. The amyloid portion of the spore wall in the Russulales is an electron-translucent wall layer covered by an electron-dense surface layer. Ontogeny of spore-wall ornamentation is similar in all genera, however diversity in the degree of ornamentation and amyloidity results from differentiation and intermixing of the two outermost enduring wall layers. Establishment of early spore asymmetry in both ballistosporic- and statismosporic-heterotropic basidiospores is highly correlated with the presence of a hilar appendix body. Observation of a demarcated cytoplasmic region, reminiscent of the hilar appendix body, in asymmetric sterigmata of orthotropic Russulales suggests that basidiospore morphology and symmetry are variable features in the Russulales. Late spore development subsequent to nuclear migration is similar in orthotropic and heterotropic Russulales. Orthotropic basidiospores appear to be released from sterigmata upon breakdown of the sterigmata. Heterotropic basidiospores are released while sterigmata are intact. Plugging layers develop in both the sterigma and in the hilar appendix. The hilar appendix plugging material appears to be produced by a plug-forming body which originates in the spore, and possibly controls liquid droplet formation during ballistosporic discharge. Ballistosporic discharge appears to be a conservative phenomenon in most Basidiomycetes resulting from a prescribed sequence of biochemical and developmental processes. The use of ballistospory and statismospory in distinguishing families and genera must be re-evaluated in the Russulales. Recognition of the Lactariaceae and Russulaceae is discussed.Ph. D.
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Denton, Tricia M. "Analyses of the relationship between stable isotope signatures, leaf epidermal morphology and the environment /." [St. Lucia, Qld.], 2003. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18307.pdf.
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Nurtjahja, Kiki. "The fine structure of dormant, ungerminated basidiospores of pluteus cervinis (fr.) kummer and agrocybe acericola (pk.) sing." Virtual Press, 1995. http://liblink.bsu.edu/uhtbin/catkey/955094.
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The fine structure of the basidiospores of Pluteus cervinus and Agrocybe acericola is described using TEM, SEM, and light microscopy.The basidiospore wall of Pluteus cervinus is bipartite. No surface ornamentation or germ pore is present. The protoplasm is surrounded by a typical membrane which lacks distinct invaginations. Spores contain much stored lipid, which is centrally located. Spores are uninucleated with the nucleus closely appressed to the cell membrane, located at the base of the spore near the hilar appendage. Mitochondria with few, well-delineated plate-like cristae are present. Endoplasmic reticulum (ER) is scant. Ribosomes occur regularly attached to the ER and outer mitochondrial membrane, as well as being densely packed throughout the cytoplasm. Various sized vacuoles containing an electron dense material are present. Microbody-like organelles are observed, which are probably glyoxysomes, since assays of malate synthase, a maker enzyme of the glyoxylate cycle, are positive.The basidiospore wall of Agrocybe acericola is composed of two distinct layers, both layers are continuous around the spores, at the germ pore the outer wall is very thin and the inner wall becomes thicker. The plasma membrane is appressed to inner wall and lacks invaginations. The protoplasm is densely packed with small granules, probably ribosomes and/or glycogen. Spores contain very little lipid with bipolar distribution. Mitochondria are well-defined and distributed in cytoplasm. Spores are binucleate with the two nuclei lying on a line nearly perpendicular to the long axis of the cell. Various size single membrane-bound vacuoles are widely distributed in the cytoplasm. These vacuoles were shown to contain acid phosphatase indicating lysosomal activity. Microbodies, probably glyoxysomes, are observed. Malate synthase assays are positive indicating the occurrence of the glyoxylate cycle.Department of Biology
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Smith, Lee Brett. "The molecular genetics of curd morphology and the domestication of cauliflower (Brassica oleracea L. var. botrytis L.)." Thesis, University of Warwick, 2000. http://wrap.warwick.ac.uk/78594/.
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The characteristic curd phenotype of the Brassica cauliflower consists of proliferating, arrested inflorescence and floral meristems. Recent analysis of the similar phenotype in the ap1-1/cal-1 mutant of the related crucifer Arabidopsis thaliana has led to speculation that the orthologous genes from Brassica oleracea L. may be responsible for this characteristic trait. Application of molecular genetic analysis to this hypothesis allows the presentation of a genetic model based on specific, mapped loci of BoCAL and BoAP 1. This model accounts for differences in the stage of arrest between the heading phenotypes of cauliflower (B. oleracea var. botrytis L.) and Calabrese broccoli (B. oleracea var. italica Plenck), and is also predictive in accounting for intermediate stages of arrest similar to those observed in Sicilian Purple types. Further molecular genetic analysis characterised three independent loci of the floral meristem identity gene BoAP 1. Integration of this data into the genetic model proposed for curd development, suggests a combination of point mutations and expression thresholds of several copies of the key meristem identity genes BoCAL and BoAP 1 respectively may account for the development of curd tissue in the Brassica cauliflower. The association of alleles of the BoCAL-a gene with the curding phenotypes of B. oleracea was also demonstrated through a survey of over 200 crop accessions. This reveals strong correlations between specific BoCAL-a alleles and discrete inflorescence morphologies, and allows the presentation of a possible scenario for the domestication of cauliflowers. Molecular genetic analysis of BoCAL-a utilising monosomic addition lines has also demonstrated the potential for integration of the genetic and cytogenetic maps of B. oleracea. Such analysis may have significant utility for physical characterisation of replicated loci in B. oleracea, prior to the development of a strong physical map. Further examination of inflorescence morphologies amongst the heading brassicas revealed a shared trait, termed Fused Inflorescence. Preliminary investigation suggests this trait may be under the control of multiple loci, providing a possible indication of the delineation between heading and sprouting B. oleracea crops.
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Li, Jianhui. "Cornichon Proteins: Unexpected Roles in Plant Pathogen Infection, ER Morphology Maintenance and Pollen Development." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/77687.
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Cornichon (CNI) proteins are a conserved family of proteins among eukaryotes, from Erv14 in the yeast Saccharomyces cerevisiae to CNI homologs (CNIHs) in mammals and plants. Erv14 functions as a cargo receptor of coat protein complex II (COPII) for protein trafficking from the endoplasmic reticulum (ER) to the Golgi apparatus, en route to their final destinations. By interacting with specific cargo proteins, CNI proteins regulate key steps of embryo polarity in Drosophila, budding in yeast, and synaptic transmission in the mammalian brain. However, we have very limited understanding of plant CNIHs. Positive-strand RNA viruses assemble their viral replication complexes (VRCs) at specific host organelle membranes. With a better understanding of host factors involved in targeting viral replication proteins to the preferred organelles, we expect to block trafficking of viral replication proteins and thus, viral infection, by manipulating the required host proteins. Brome mosaic virus (BMV) is a model of positive-strand RNA viruses and its replication can be recapitulated in yeast. Importantly, BMV replication protein 1a is the only required viral protein to form VRCs at the perinuclear ER membrane in yeast. I demonstrate that Erv14 and COPII coat proteins are required for targeting BMV 1a to the perinuclear ER in yeast, suggesting a novel function of COPII vesicles in protein trafficking to the perinuclear ER membrane and in the BMV VRC formation. As for cellular functions, I show that plant CNIHs complement the defective distribution of BMV 1a in yeast mutant lacking Erv14. Taking advantage of Arabidopsis thaliana knockout mutants and knockdown of gene expression in Nicotiana benthamina, I also discover that CNIHs unexpectedly play crucial roles in pollen development, infection of a bacterial pathogen, and maintenance of ER tubules. I further confirm that CNI proteins are also required for maintaining ER tubules in yeast, suggesting a novel and conserved role in shaping ER morphology. Therefore, these findings indicate the functional diversity and redundancy of CNI proteins in key cellular processes and suggest a novel strategy to control plant pathogenic viruses and bacteria by manipulating plant CNIHs.Ph. D.
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Frank, Daniel Lee. "Plant-insect interactions between female dogwood borer and apple." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/30215.
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A rearing methodology for dogwood borer was developed, using standardized procedures at each developmental stage. These methods enabled the establishment of a laboratory colony and efficient production of synchronized cohorts of each of its lifestages throughout the year for specific experimental needs.
The behavioral repertoire shown by mated female dogwood borer in an apple orchard was characterized and quantified and the diel periodicity with which those behaviors occurred was determined. Mated females were easily recognized, based on their characteristic casting flight directed toward areas below the graft union of apple trees, and were observed more frequently during the late afternoon and evening. Casting flight, probing with the ovipositor, and oviposition were the most frequent behaviors observed, but the duration of those behaviors was relatively short compared with the much lengthier periods of resting behavior that typically occurred within the canopy.
Data from a previous, three-year study in two newly planted apple orchards were subjected to geostatistical analyses to examine the temporal and spatial patterns of infestation by larval dogwood borer and to gain further information about the spatial scales at which oviposition occurs. There were moderate to high degrees of aggregation of dogwood borer infestations on neighboring apple trees, with ranges of spatial dependence from 7.50â 19.87 m. No directionality was observed in the spatial autocorrelation of infestation and it appears that females utilized oviposition sites equally along and across orchard rows. The aggregated nature of infestations requires that random, independent samples must be taken from a number of sample pairs at distances greater than the range of spatial dependence to ensure that sample data are not autocorrelated. Alternatively, an efficient sampling program for mapping dogwood borer infestation can be achieved by limiting sample points to distances within the range of spatial dependence. These sample points can be used in interpolating algorithms, such as kriging, to predict infestation at unsampled locations in space for use in site-specific pest management programs.
The external morphology of male and female dogwood borer antennae and their sensilla were examined using light and scanning electron microscopy to characterize, measure and compare the types, number, and distribution of sensilla. Although the general shape and size of male and female antennae were similar, those from females possessed a greater number of generally smaller antennal flagellomeres. The flagellum of both male and female antennae contained seven sensillum types including auricillica, basiconica, chaetica, coeloconica, squamiformia, styloconica, and three subtypes of sensilla trichoidea. With the exception of sensilla basiconica, which were present in roughly equal numbers on male and female antennae, all other sensillum types were significantly more abundant on female antennae. The antennae of female dogwood borer appear well equipped to perceive olfactory stimuli, based on the types and number of sensilla present.
Coupled gas chromatography and electroantennogram detection (GC-EAD) analyses of headspace collections from damaged and undamaged tissues from apple and dogwood trees were conducted to examine and compare the antennal responsiveness of female dogwood borer to host plant volatiles. A total of 16 and 9 compounds from apple and dogwood tissues, respectively, consistently elicited an antennal response in females. There were no differences in the response of antennae from virgin and mated females, and the amplitude of the female response to host odors was greater than that of males. Six compounds were identified from the headspace collections from apple trees, four of which (octanal, nonanal, decanal, and methyl salicylate) were identified from all apple tissues sampled. A novel compound, α-bergamotene, was identified from injured apple bark, from apple burr knots infested with dogwood borer larvae and from larval dogwood borer frass, and appears to be produced by apple trees in response to injury. Another novel compound, methyl-2,4-decadienoate, was identified from infested burr knot tissue and appears to be produced in response to an insect-plant interaction. Two compounds, hexanoic and nonanoic acid, were identified from headspace collections from dogwood trees.
Numerous approaches were used to examine the behavioral response of mated female dogwood borer to host plant headspace collections and to individual compounds from those collections that elicited a strong and repeatable antennal response. Under both natural and semi-natural conditions in the field and in laboratory bioassays, neither attraction/orientation or consistent oviposition were documented and it is apparent that correlating the electrophysiological and behavioral responses of mated female dogwood borer to olfactory stimuli from their host plants will require further research on bioassay development.Ph. D.
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Cowie, Neil R. "The dynamic morphology of the wood anemone, Anemone nemorosa L. in an ancient coppice wood." Thesis, University of East Anglia, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357181.
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Meeks, Robin. "Analysis and modelling of morphology and productivity of field-grown cut-flower crops." Thesis, University of Nottingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267671.
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Campbell, Thomas Jay. "A genetic and physiological analysis of hph and bul-D : two growth altered mutants of Arabidopsis /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p3137682.
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Xu, Su. "Impact of agro-forestry systems on coffee yield, coffee plant morphology, physical and chemical attributes of green coffee beans and aroma generation of roasted coffee beans." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/48086/.
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A long experiment has been established since 2000 at CATIE (Tropical Agricultural Research and Higher Education Center), Turrialba, Costa Rica. Twenty agro-forestry systems with different shade types and managements (organic and non-organic) consisting of an incomplete randomized block-design with shade tree as main effect and subplots represented by management were set up. The mean 13-year yield, bienniality index (BI) of coffee yield, pruning, shade cover and morphology (height, diameter, total branches and productive branches) of coffee plants in these agro-forestry systems were measured. The effects of different managements and shade types on the physical and chemical attributes of green coffee beans and aroma and colour generation of roasted coffee beans were investigated. The organic management always showed the more stable production, while the coffee yield and morphology were always worse under the intensive organic (IO) management than under the intensive conventional (IC) management. Comparing with the moderate conventional (MC) management, the intensive organic (IO) management did not only have a similar or even higher productivity, but it also had higher total lipid and protein in the green beans and a stronger ability to generate more flavour and colour. The full sun system had a higher total coffee yield and bienniality index (BI) of coffee yield, green bean density and total protein content and greater flavour generation and colour after roasting. Comparing with the timber system, the service system did not only have the higher coffee yield and better coffee plant morphology, but it also produced green beans with higher total protein and roasted beans with the more flavour and colour. Comparing with the non-legume shade tree, the legume shade tree only influenced the total protein content of green coffee beans and further improved the performance of flavour and colour in the roasted coffee beans.
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Brändström, Jonas. "Morphology of Norway spruce tracheids with emphasis on cell wall organisation /." Uppsala : Swedish University of Agricultural Sciences, 2002. http://diss-epsilon.slu.se/archive/00000236/.
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Thesis (doctoral)--Swedish University of Agricultural Sciences, 2002.Thesis documentation sheet inserted. Appendix reprints four papers and manuscripts, three co-authored with others. Includes bibliographical references. Issued also electronically via World Wide Web in PDF format; online version lacks appendix.
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Jassim, Raad Ahmed. "Effect of haloxyfop and fluazifop on morphology and fatty acid synthesis of annual blue grass (Poa annua L.) seedlings." Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/186541.
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Haloxyfop-methyl, methyl-2-[4-[[3-chloro-5-(triflouromethyl)-2-pyridinyl]oxy]phenoxy]propanoic acid] and fluazifop-butyl, (+)-butyl-2-[4-[[5-(trifluoromethyl)-2-pyridinyl] oxy]phenoxy]propanoic acid are used for selective control of annual and perennial gramineous weeds in broadleaf crops. Annual blue grass (Poa annua L.) is controlled by haloxyfop-methyl but not by fluazifop-butyl. Research was conducted to determine the effect of each herbicide on growth, morphology, lipid synthesis and acetyl-CoA carboxylase activity, of this species, and to determine physiological mechanism of annual blue grass tolerance to fluazifop-butyl. Techniques used in this research were growth measurements, light and electron microscopy, TLC, and enzyme assay for acetyl-CoA carboxylase. Haloxyfop-methyl at 15 μM when applied preemergence caused 96% reduction of root growth of annual blue grass whereas fluazifop-butyl at 15 μM caused 42% reduction of root growth. Haloxyfop-methyl at 5 μM and 15 μM caused 35 and 96% inhibition of leaf growth, respectively. Fluazifop-butyl at same rates caused 19 and 32% inhibition of leaf growth. Haloxyfop-methyl at 5 and 20 μM when applied postemergence caused 20 and 56% reduction of leaf growth, respectively. Fluazifop-butyl at same rates caused 11 and 21% reduction of leaf growth. Haloxyfop-methyl at 20 μM caused 80% reduction of annual blue grass seedlings dry weight whereas fluazifop-butyl caused 40% reduction. Morphological studies showed that postemergence applications of 20 μM of haloxyfop-methyl caused severe tissue injury whereas same rates of fluazifop-butyl caused less injury. Ultrastructural studies showed that haloxyfop-methyl at 20 μM caused disruption, elongation, and reduction of chloroplast thylakoids whereas fluazifop-butyl caused less injury to thylakoids. Acetyl-CoA carboxylase activity from annual blue grass was inhibited by about 40% in the presence of 10 μM haloxyfop acid but fluazifop acid caused 6.5% inhibition. The lipid content was reduced by 56% in seedling treated with 20 μM haloxyfop-methyl whereas fluazifop-butyl caused 19% inhibition. Fluazifop-butyl at all rates caused no loss of lipid classes whereas haloxyfop-methyl at 10 and 15 μM caused loss of phospholipid and glycolipid which are part of the cellular membranes. Haloxyfop caused greater reduction of leaf and root growth, greater degree of tissue injury and chloroplast distortion, greater inhibition of acetyl-CoA carboxylase activity than fluazifop. All these effects lead to degradation of cellular components and eventually to the death of the plant.
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Engel, Thaíssa Brogliato Junqueira 1989. "Estudos cariotípicos em Griffinia Ker Gawl e espécies relacionadas (Amaryllidaceae)." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/314933.
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Orientador: Eliana Regina Forni MartinsDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: O gênero Griffinia Ker Gawl pertence à subfamília Amaryllidoideae que, junto às subfamílias Agapanthoideae e Allioideae, compõem a família Amaryllidaceae, com cerca de 73 gêneros e 1605 espécies. As Amaryllidaceae, incluindo as Griffinia, são apreciadas pelas suas flores e cultivadas para a jardinagem e ornamentação. Endêmico do Brasil, esse importante gênero está ameaçado de extinção pela constante degradação de seu ambiente natural, sendo que muitas espécies não foram mais encontradas na natureza e nem em cultivo. A taxonomia de Griffinia é bastante dificultada pela morfologia floral e vegetativa bastante semelhante entre algumas espécies, e pela variação morfológica dentro de uma mesma espécie, ocasionada pelo isolamento entre populações e pela existência de diferentes citótipos. Os objetivos deste trabalho foram obter o cariótipo de diferentes espécies de Griffinia e de espécies proximamente relacionadas, e fornecer à sistemática informações que auxiliem na compreensão das relações filogenéticas e evolutivas das espécies desse gênero. Foram estudadas 10 espécies e duas morfoespécies não identificadas de Griffinia, bem como quatro espécies de gêneros próximos. Pontas de raízes coletadas dessas espécies foram pré-tratadas em colchicina e fixadas em solução Farmer para a produção de lâminas com metáfases mitóticas. Foram determinados número e morfologia cromossômicos e realizados bandamentos com os fluorocromos cromomicina3 (CMA3) e 4',6-diamidino-2-fenilindol (DAPI), e in situ fluorescent hybridization (FISH) com DNA ribossomal (DNAr 5S). Todas as espécies de Griffinia apresentaram 2n=20. Os números cromossômicos para as espécies analisadas de Eithea, Hippeastrum, Tocantinia e Worsleya foram 2n=18, 44, 22, e 42 respectivamente. Foram observadas espécies de Griffinia com duas, quatro, cinco e seis bandas CMA3+. De um a três sítios de DNAr 5S foram observados em dois a seis pares cromossômicos, em posição terminal, subterminal ou pericentromérica. Para cada espécie, foi observado um padrão único de distribuição de sítios de DNAr 5S, sendo assim possível a delimitação de espécies por meio das técnicas citogenéticas aplicadas. As espécies do grupo reportado na literatura como complexo Liboniana apresentaram semelhanças cariotípicas que podem corroborar a proximidade entre espécies: possuem apenas um par cromossômico com banda CMA3+ e dois pares cromossômicos com sítios de DNAr 5S. Variações cariotípicas foram observadas não apenas entre as espécies, mas também entre populações de uma mesma espécie. Casos de variação intraespecífica são conhecidos para plantas. Contudo, essa variação pode não ser uma variação interpopulacional, mas sim, reflexo da dificuldade taxonômica no gênero. Os resultados obtidos nesse estudo, apontam a citogenética como uma ferramenta útil na delimitação dos gêneros e espécies, e no reconhecimento de grupos dentro de Griffinia.
Abstract: The genus Griffinia Ker Gawl belongs to the subfamily Amaryllidoideae which together with the subfamilies Agapanthoideae and Allioideae, forms the Amaryllidaceae family, with about 73 genera and 1605 species. Amaryllidaceae plants, including Griffinia, are aprecciated because of their flowers and cultivated for gardening and ornamentals. Endemic to Brazil, the genus is endangered by the continuous degradation of their natural environment, and many species have not been found in nature. Taxonomy of Griffinia is very complicated because of its vegetative and floral morphology, which are quite similar between some species. There is also some morphological variation within a single species, caused by the isolation between populations and the existence of different cytotypes. The aim of this study was to obtain the karyotype of different species of Griffinia and closely related species, thus providing for systematic studies some information to assist in the understanding of the evolutionary and phylogenetic relationships of the species of this genus. We studied 10 species and two unidentified morphospecies of Griffinia, as well as four species of closely related genera. Root tips collected from these species were pretreated with colchicine and fixed in Farmer solution for the production of slides with metaphasic cells. We determined the number and chromosomal morphology. We performed banding with chromomicin3 (CMA3) and 4',6-diamidino-2-phenilindole (DAPI) fluorochromes and fluorescent in situ hybridization (FISH) with ribosomal DNA (5S rDNA). All Griffinia species presented 20 chromosomes. Chromosome numbers for the analyzed species of Eithea, Hippeastrum, Tocantinia and Worsleya were 2n= 18, 44, 22 and 42 respectively. Griffinia species presented two, four, five or six CMA3+ bands. One to three 5S rDNA sites were observed in two to six chromosome pairs in the terminal, subterminal or pericentromeric position. For each species, there was a unique pattern of distribution of DNAr 5S sites, so it is possible to delimitate species trough this cytogenetic technique. The species of a group reported in the literature as Liboniana complex showed similar karyotypes that can corroborate the closeness among the species of the group: they have only one chromosome pair with a CMA3+ band and two chromosome pairs with 5S rDNA sites. We observed karyotypic variations not only among species but also between populations of the same species. Cases of intraspecific variation are known for plants. However, this variation may be either an interpopulational variation, or a simple reflection of the difficulty in taxonomy of the genus. The data found at this analysis proved cytogenetic studies to be a quite useful tool in the delimitation of genera and species, and recognition of groups within Griffinia.
Mestrado
Biologia Vegetal
Mestra em Biologia Vegetal
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Osman, Mohammed A. "Effect of water stress on the physiology, growth, and morphology of three pearl millet genotypes." Diss., The University of Arizona, 1988. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1988_11_sip1_w.pdf&type=application/pdf.
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Lock, Allan Arthur. "The use of changing plant morphology in developing a simulation model for winter wheat (Triticum aestivum)." Thesis, University of Aberdeen, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274802.
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Leaf appearance of winter wheat in relation to thermal time has been studied during the past twenty years but as yet models have insufficient accuracy for predictive use.
This project investigated different methodologies used previously to describe leaf appearance. These were applied to data collected from tagged plants to compare results from the different systems and investigate possibilities for unification and improving accuracy. The different methodologies could not be unified. Phyllochrons, measured as thermal time intervals between either leaf tip or ligule appearances, varied throughout the life of the plant, those calculated by ligule appearances produced phyllochrons least affected by seed size. Lamina length was influenced by total solar radiation received during its external appearance. Lamina extension rates, calculated as mm 0Cd-1, were correlated with solar radiation and influenced by ontogenetic rank. Calculating proportional lamina appearance values using self-referencing methodology produced fewer errors than by referencing the previous lamina, but results from both systems were influenced by seed weight. Seed weight influenced the 'tip to indent' length of a lamina, but not the 'indent to ligule' length and its effect was greatest on leaf two thereafter diminishing. The tip of the second leaf appeared earlier in plants grown from heavy seed compared with light seed.
Internal leaf development in plants was investigated by dissection. Lower ridge extension continued until awn extension occurred at the apex, indicating that final leaf number might not be determined until then. The ligule on one leaf remained synchronised to an 'indent' on the next lamina until the ligule emerged. Several developing leaf systems were similarly 'mechanically linked' and this may explain similarities between phyllochrons. The project identified that the amounts of stored or received energy available for assimilation influenced rates of leaf appearance and possibly the number of leaves. The process was undoubtedly regulated by temperature and possibly influenced by ontogenetic rank.
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Xiao, Qiying. "PLANT RESPONSE TO MAGNESIUM AVAILABILITY: ROOT MORPHOLOGY ADAPTATION AND INVESTIGATION OF A ROLE FOR THE CLOCK." Doctoral thesis, Universite Libre de Bruxelles, 2017. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/252836.
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Understanding the dynamical bases of the interaction between the plant mineral nutrition and the circadian clock could contribute to improve crop yield and resistance to adverse conditions, such as mineral element deficiencies. Magnesium is an essential element that catalyzes more than six hundred enzymatic reactions and occupies the center of the chlorophyll structure in plants. Physiological targets of magnesium deficiency are generally better described in aerial than in belowground organs. In this thesis, we first characterized the root morphology of the model species Arabidopsis thaliana (Columbia-0) in response to magnesium supply during in vitro culture. The length of primary root and the number and length of lateral roots decreased during magnesium depletion. A local magnesium-rich source does not enhance the root foraging capacity, unlike some other major nutrients. Auxin and abscisic acid emerged as two hormones shaping root morphology in response to magnesium deficiency. Second, we investigated the natural variation of the root morphology response to magnesium supply in Arabidopsis. Thirty-six accessions were screened in vitro. Compared to the reference Columbia-0, some accessions had higher number and length of lateral roots at low magnesium supply. Root or shoot magnesium concentrations did not implicitly correlate with the root morphological traits. However, shoot calcium and root phosphorus concentrations correlated positively with the lateral root number and length, while root iron negatively with the length of primary root. Third, we focused on the interaction between the plant magnesium nutrition and the circadian clock circuit. We tested for a possible involvement of PHYTOCHROME INTERACTING FACTOR 3-LIKE 1 (PIL1) - a clock-associated gene that is down-regulated during magnesium depletion - in morphological and physiological responses, and for a circadian connection of PIL1 in the context of magnesium deficiency. The phenotypes of loss-of-function and overexpression lines did not reveal a major role of PIL1 in the magnesium deficiency symptom manifestation but rather in the plant mineral profile. The expression of PIL1 was apparently not under any circadian control. However, PIL1 seemed to regulate the expressions of some core clock genes (CCA1, LHY and PRR9), which were also targets during magnesium deficiency. In conclusion, PIL1 has a link with the circadian rhythm machinery but it does not emerge as a pivotal regulator of magnesium stress responses.Doctorat en Sciences
info:eu-repo/semantics/nonPublished
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Wikberg, Per-Erik. "Occurrence, morphology and growth of understory saplings in Swedish forests /." Umeå : Dept. of Silviculture, Swedish Univ. of Agricultural Sciences, 2004. http://epsilon.slu.se/s322.pdf.
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Correia, António Henrique Costa Gomes Soares. "Designing Eucalyptus globulus Labill. seedlings morphology using nitrogen fertilization during nursery production." Master's thesis, ISA, 2010. http://hdl.handle.net/10400.5/15195.
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Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de AgronomiaA Eucalyptus globulus Lab. Situa-se como a terceira espécie mais importante ao nível da área florestal Nacional, de extrema importância na indústria florestal, utilizada como material base na produção de pasta de papel (CELPA, 2009). Neste trabalho produziram-se plantas de Eucaliptus globulus, utilizando quatro níveis de fertilização, em condições semelhantes às utilizadas em viveiros comerciais com o objectivo de (1) modelar o crescimento (dimensões das plantas e periodo de produção), tendo em conta os limites legais morfológicos impostos por decreto lei (Decreto-Lei) e (2) desenvolver indicadores de qualidade das plantas de forma a estimar a sua performance no campo. Os resultados demonstram que existiu correlação entre crescimento de raízes finas e a performance no campo. A correlação observada entre conteúdo de clorofila e o conteúdo em azoto das plantas permite optimizar a produção, pela avaliação das necessidades em azoto que as plantas apresentem. A fertilização azotada revelou um grande impacto no crescimento potencial das raízes. O fornecimento de 40 mg de N (nível de fertilização N40) produz plantas com maior capacidade de sobrevivênvia e performance, aplicado a partir dos 2 meses de produção--------------------------------ABSTRACT - Tasmanian blue gum (Eucalyptus globulus Labill) is the third most important specie in the Portuguese forest cover, highly relevant in the forestry industry, and raw material used for pulp and paper production (CELPA, 2009). Growth of this short rotation species in the field is dependent on the initial growth in the nursery. In this experiment, seedlings of Eucalyptus globulus Labill were grown with four levels of Nitrogen (N) fertilization, under growth conditions similar to those used in nursery commercial production, with the objectives of (1) modelling growth (planting stock size and production period), taking into account the legal regulation limits imposed by law (Decreto-Lei) and (2) to develop indicators of seedlings quality to estimate their performance in the field. Results showed high correlation between fine roots growth and field performance. The correlation between chlorophyll content and N seedling content observed allows to optimize seedling production, through the assessment of N needs of seedlings. N nutrition reveals high impact on root growth potential. 40 mg of total supplied N (N40 nutrition level) produces good quality seedlings, applied since 2 month seedlings
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Ruhland, Beverlee M. "Morphological aspects of seedling establishment in four temperate region Phorandendron spp." PDXScholar, 1986. https://pdxscholar.library.pdx.edu/open_access_etds/3702.
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Four species of Phoradendron were examined for seedling morphology: P. bolleanum subsp. densum (on Juniperus), P. californicum (on Prosopis), P. juniperinum subsp. juniperinum (on Juniperus, P. villosum subsp. villosum (on Quercus). The main species used in the study was P. juniperinum, using the other species for comparison. The initial shoot(s) of P. juniperinum may develop from the epicotyl of the developing seedling, from adventitious buds which arise from a cushion of tissue, termed the haustorial cushion, formed beneath the holdfast, or from both positions. When shoots arise only from adventitious buds the original seedling remains attached in a lateral position, often persisting for a number of years, giving the false impression of an autoparasite establishing itself near the base of the plant. In P. bolleanum and P. villosum, initial shoots arise from the epicotyl although adventitious shoots may also develop, particularly in P. bolleanum. In contrast, P. californicum shoots are entirely adventitious in origin, and the initial seedling can frequently be seen near the center of the cluster of adventitious shoots. Cotyledons of all species in the study were found to be persistent and possess a distinctive tip probably resulting from the site of attachment to the endosperm. These distinctive, persistent cotyledons and other clearly identified morphological features, allow to readily distinguish between plumular and adventitious shoots.
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O'Connell, Dean Michael, and n/a. "Plant-arthropod interactions : domatia and mites in the genus Coprosma (Rubiaceae)." University of Otago. Department of Botany, 2009. http://adt.otago.ac.nz./public/adt-NZDU20090807.160026.
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Plant-based defence mutualisms involve aspects of plant morphology that influence the performance of plant parasites, their natural enemies and trophic interactions. Leaf domatia, small indentations on the underside of leaves, can be structurally complex, and are often inhabited by potentially beneficial mites and other arthropods. Plant morphological traits such as domatia that enhance mutualistic relationships may result in increased plant growth rates, and reproductive success. New Zealand supports ~60 plant species that have domatia, the most speciose genus being Coprosma. The aim of this thesis was to examine factors that affect the production of leaf domatia and their relationship with foliar mite assemblages. The three main objectives of this thesis are: First, to investigate the production of foliar domatia and their susceptibility to limited resources, particularly to carbon availability. Second, to test if domatia are inducible structures during leaf ontogeny in the presence of foliar mites and/or fungi. Finally, to explore the effect of domatia availability on foliar mite assemblages on leaves with and without resident mites. This thesis tested the stated objectives using C. lucida, C. ciliata, C. foetidissima and C. rotundifolia, with a combination of field investigations and controlled manipulative experiments. The cost of domatia production was investigated using two field surveys and two controlled experiments. Under natural conditions the relationship between leaf morphology and domatia were measured in situ and across an altitudinal gradient. The experimental manipulations used carbon and nutrient stress, induced by temperature, light and fertilizer application. The second objective was experimentally tested under field conditions by manipulating foliar mites and fungal densities on C. rotundifolia. The third objective was investigated by manipulating domatia availability on C. lucida shrubs across three different vegetation types. Under field conditions, the number of domatia per leaf was associated with leaf morphology in C. lucida and C. foetidissima, but not C. rotundifolia. Foliar carbon showed a positive, but weak association with domatia production in C. foetidissima and C. ciliata. Altitudinal induced-carbon stress on domatia production was ambiguous. Domatia production in C. foetidissima was positively associated to altitude in field survey (1), and negatively associated in the second survey, with no correlation found between carbon and altitude. Experimental C. rotundifolia shrubs held under elevated night-time temperatures showed a 2.5 fold increase in respiration, a 34% to 91% decrease in daily carbon gain, and 38% decrease in domatia per leaf mass. Domatia production showed no significant differences under nutrient stress. The results showed little evidence to support a role for induction of domatia. Domatia production in new leaves was similar across all experimental treatments. Diverse vegetation types supported 60% higher mite species. Leaves with domatia supported ~22 to 66% higher mite densities, greater colonisation success and more diverse mite assemblages, than those without domatia. In the pastoral vegetation, the absence of predatory mites on experimental shrubs resulted in no differences in fungivorous mite densities regardless of domatia availability. Plant investment in foliar domatia appears associated with the number of available sites on the leaf under field conditions. The role of carbon availability during leaf ontogeny suggests a complex and highly variable association with domatia production. Domatia are constitutive defence structures that influence mite assemblages, mediating both beneficial and antagonistic relationships. This thesis concludes that domatia are in part, carbon-based non-inducible structures that influence mite assemblages, plant-mite and mite-mite interactions, and increase the probability of successful colonisation.
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Edelman, Sara M. "Morphology, Architecture and Growth of a Clonal Palm, Acoelorrhaphe wrightii." FIU Digital Commons, 2017. http://digitalcommons.fiu.edu/etd/3201.
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Palms provide valuable commercial resources in the tropics and are dominant species in tropical lowland forests. While general biology of palms is well studied, there are gaps in the literature on palm growth through life stages and in response to environmental conditions. Literature gaps on palm growth could be caused by the slow growth of palms; it is difficult to monitor morphology and architecture for the periods of time necessary to capture changes. Acoelorrhaphe wrightii is a threatened palm native to southern Florida with an unusual adult architecture. The purpose of this dissertation was to study growth A. wrightii throughout its life stages and in response to changes in environmental conditions. In order to do study growth, I first had to understand the evolutionary history and types of vegetative branching in palms to identify vegetative branching possibilities in A. wrightii. I described branching types for 1903 species from all 181 genera using literature reviews and hands-on analysis. I then studied adult morphology and architecture in a common garden setting by monitoring leaf morphology, ramet growth and architecture of A. wrightii in two gardens in Miami, FL, over a two year period. I tested the effects of water and light on germination and growth of juvenile plants in a mesocosm where water and light were manipulated, following growth for a year. Finally, I compared leaf morphology and architecture of adult individuals in four populations in Belize and Florida. I found five branching types were present in the palms: lateral axillary branching, shoot apical division, false vivipary, abaxial branching and leaf-opposed branching. In the garden, Acoelorrhaphe wrightii displayed two types of lateral axillary branching: basal suckering and rhizomatous branching. The two branching types produced tiers in adult clones, which were used to model architecture. Ramets had an establishment period and growth varied seasonally in establishing and established phases. Low water levels and full sun yielded greater germination of A. wrighti and produced juveniles with a greater number of leaves, more root mass and more branches. Variability between populations and environmental conditions was observed in adult individuals in the field but differences were minimal.
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Hinsberg, Arjen van. "On phenotypic plasticity in Plantago lanceolata : light quality and plant morphology = Over fenotypische plasticiteit in Plantago lanceolata /." [S.l. : s.n.], 1996. http://www.gbv.de/dms/bs/toc/227500458.pdf.
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Boothroyd, Richard James. "Flow-vegetation interactions at the plant-scale : the importance of volumetric canopy morphology on flow field dynamics." Thesis, Durham University, 2017. http://etheses.dur.ac.uk/12363/.
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Vegetation is abundant in rivers, and has a significant influence on their hydraulic, geomorphological, and ecological functioning. However, past modelling of the influence of vegetation has generally neglected the complexity of natural plants. This thesis develops a novel numerical representation of flow through and around floodplain and riparian vegetation, focusing on flow-vegetation interactions at the plant-scale. The plant volumetric canopy morphology, which comprises the distribution of vegetal elements over the three-dimensional plant structure, is accurately captured at the millimetre scale spatial resolution using Terrestrial Laser Scanning (TLS), and incorporated into a Computational Fluid Dynamics (CFD) model used to predict flow. Numerical modelling, with vegetation conceptualised as a porous blockage, is used to improve the process-understanding of flow-vegetation interactions. Model predictions are validated against flume experiments, with plant motion dynamics investigated, and analysis extended to consider turbulent flow structures and the plant drag response. Results demonstrate the spatially heterogeneous velocity fields associated with plant volumetric canopy morphology. The presence of leaves, in addition to the posture and aspect of the plant, significantly modifies flow field dynamics. New insights into flow-vegetation interactions include the control of plant porosity, influencing ‘bleed-flow’ through the plant body. As the porosity of the plant reduces, and bleed-flow is prevented, the volume of flow acceleration increases by up to ~150%, with more sub-canopy flow diverted beneath the impermeable plant blockage. Species-dependent drag coefficients are quantified; these are shown to be dynamic as the plant reconfigures, differing from the commonly assigned value of unity, and for the species’ investigated in this thesis range between 0.95 and 2.92. The newly quantified drag coefficients are used to re-evaluate vegetative flow resistance, and the physically-determined Manning’s n values calculated are highly applicable to conveyance estimators and industry standard hydraulic models used in the management of the river corridor.
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Ralston, S. "Rehabilitation of dune forests in KwaZulu-Natal: predicting slow colonisers and vulnerable species based on plant morphology." Thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/26025.
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González, Esteban Roberto. "Transformação genética de Eucalyptus grandis e do híbrido E. grandis x E. urophylla via Agrobacterium." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/11/11137/tde-23102002-174613/.
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A produção de papel e celulose representa um importante componente do setor industrial brasileiro, com perspectivas a expandir-se nos próximos anos, sendo o Brasil o principal produtor de celulose a partir de eucalipto. A técnica de transformação genética pode contribuir significativamente para introduzir caracteres de interesse econômico que permitam: aumentar a produtividade da cultura, resistência a doenças e melhorar a qualidade da madeira. Os sistemas de transformação genética requerem um sistema de regeneração de plantasin vitro eficiente associado a um sistema de integração estável do transgene ao genoma das mesmas. Por este motivo o trabalho foi dividido em duas etapas. A primeira parte foi orientada para o desenvolvimento de um sistema de regeneração eficiente e reproduzível por organogênese indireta tanto para E. grandis como para o híbrido E. grandis x E. urophylla. Foram realizados experimentos para avaliar-se o efeito dos diferentes tipos de explantes, genótipos, concentrações de reguladores de crescimento e taxa regenerativa de diferentes clones. A regeneração de cotilédones e folhas de plântulas apresentou uma eficiência de 30 % e 25 respectivamente. Além destes sistemas, o protocolo de regeneração a partir de folhas de clones comerciais de E. grandis mostrou-se bastante eficiente. Na segunda parte do trabalho desenvolveu-se a metodologia de transformação genética de E. grandis e E. grandis x E. urophylla, via Agrobacterium tumefaciens. O efeito de diferentes tempos de pré-cultivo dos explantes, tempo de sonicação, influência dos meios de co-cultivo e dos agentes seletivos, foram avaliados. As sementes pré-cultivadas durante 2 e 15 dias apresentaram as maiores porcentagens de expressão da???? -glucuronidase (GUS) (21,7 e 37,4 %, respectivamente), quando sonicadas. As sementes pré-cultivadas por 2 dias apresentaram mais de 90 % das áreas transformadas localizadas nos cotilédones e no colo. Já as sementes pré-tratadas por 15 e 17 dias apresentaram 60 % das áreas de transformação localizadas no primeiro par de folhas. A condição mais adequada para a transformação de cotilédones foi a sonicação por 120 s, de sementes pré-cultivadas por 2 dias, sendo o melhor meio de co-cultivo o MS. Plantas transgênicas de E. grandis e E. grandis x E. urophylla foram obtidas, abrindo assim uma grande perspectiva na área de melhoramento do eucalipto, com a introdução das técnicas de transformação gênica.The pulp and paper industry is an important sector of Brazilian industry, showing good perspectives of expansion, once Brazil is the main cellulose producer from Eucalyptus. Genetic transformation may contribute to increase productivity by the introduction of desirable traits, such as pest resistance and improvement of wood quality. However, the prerequisite for the success of the transformation strategy is the establishment of an efficient, in vitro, regeneration system. The recovery of transgenic plants is only possible from cells that respond to both processes: the integration of the transgene and also the plant regeneration. Hence, this work was divided in two phases. The first study was carried out to develop an efficient and reproducible regeneration system by indirect organogenesis of E. grandis and the hybrid E. grandis x E. urophylla. The experiments were organized to evaluate the effect of the different seedling explants, genotypes, hormonal concentration and regenerative rate of clonal material. The regeneration efficiency of cotyledons and leaves of seedling explants was around 30 % and 25 %, respectively. In addition, an efficient regeneration protocol of Eucalyptus grandis was developed which uses leaf explants from clonal plants. In the second study the procedure for genetic transformation of E. grandis and E. grandis X E. urophylla using Agrobacterium is described. Several experimental parameters were evaluated such as the length of precultivation, the sonication effect, the cocultivation media and the selective agents. Germinating seeds of 2 and 15 days had the highest percentage of ? -glucuronidase (GUS) expression (21.7% and 37.4%, respectively), when sonicated. Germinating seeds imbibed for 2 days showed over 90% of the blue sectors localized in cotyledons and in the intersection of the hypocotyls and roots, whereas, seedlings that had germinated for 15-17 days had an average of 60% of the transformed sectors localized in the first pair of leaves. The best condition for an efficient genetic transformation was 2-day precultivation, associated with 120-s sonication and MS media for cocultivation. Transgenic plants of E. grandis and E. grandis x E. urophylla were obtained by this method, opening an important perspective for the breeding of Eucalyptus through genetic transformation techniques.
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Moreira-Coneglian, Inara Regiane. "Morfologia e ontogenese do pericarpo e da semente de Eugenia punicifolia (H. B. & K.) DC., Myrcia bella Camb. e Campomanesia pubescens (DC.) Berg (Myrtaceae)." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315670.
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Orientador: Sandra Maria Carmello-GuerreiroDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: O cerrado vem sendo destruído e os aspectos estruturais de suas plantas são pouco conhecidos perante sua diversidade. A maioria das espécies nativas de Myrtaceae, uma das mais representativas da flora brasileira e dos cerrados, não possui estudos de suas estruturas reprodutivas; as análises de frutos e sementes de membros desta família limitam-se a espécies de interesse econômico e raramente envolvem aspectos anatômicos e ontogenéticos. Este trabalho objetiva detalhar a morfologia e ontogênese dos frutos e sementes de Eugenia punicifolia, Myrcia bella e Campomanesia pubescens, espécies comumente encontradas no cerrado sensu lato, comparando-as. O material foi processado seguindo técnicas anatômicas usuais para inclusão em resina plástica. Nas três espécies, tanto na parede ovariana quanto no pericarpo, destaca-se a região fundamental, dividida em três áreas, a grande freqüência de células com conteúdo fenólico e a presença de cavidades secretoras com conteúdo lipídico. Os óvulos são campilótropos; em E. punicifolia, a calaza é extensa e há hipóstase; nas outras espécies, a calaza é menos extensa e não observa-se hipóstase. Durante o desenvolvimento dos frutos, há, inicialmente, intensa atividade mitótica em todas as regiões dos frutos. Formam-se espaços intercelulares no mesocarpo de E. punicifolia e M. bella; em C. pubescens, diferenciam-se esclereídes isoladas no mesocarpo e as camadas mais internas do mesocarpo e o endocarpo concrescem com o tegumento seminal. No fruto maduro, as células mesocárpicas alongam-se radialmente, originando a polpa carnosa nas três espécies. Embora pertençam a subtribos diferentes, o desenvolvimento dos pericarpos de E. punicifolia e M. bella mostraram-se bastante semelhantes; C. pubescens apresentou características particulares, seguindo o padrão descrito para o gênero. Durante o desenvolvimento seminal, ocorre maior crescimento na região antirafeal, originando sementes reniformes. Em Eugenia punicifolia, a calaza se expande, evidenciando o desenvolvimento paquicalazal da semente. Em Myrcia bella e Campomanesia pubescens, desenvolve-se a hipóstase. Em M. bella, forma-se uma pericalaza. Em C. pubescens, a expansão da calaza é restrita ao hilo. As células da exotesta alongam-se radialmente. Divisões celulares aumentam o número de camadas da mesotesta, e em E. punicifolia e M. bella, esta torna-se fenólica em todo o envoltório seminal. A epiderme interna da testa e o tegumento interno não apresentam modificações. O eixo embrionário de E. punicifolia é curto e contínuo com os cotilédones espessos e parcialmente concrescidos; os de M. bella e C. pubescens são bastante alongados. Em M. bella, identifica-se dois cotilédones foliáceos torcidos. Em C. pubescens, os cotilédones são bastante reduzidos e não foram encontrados anatomicamente. As sementes maduras são campilótropas. A exotesta de Eugenia punicifolia é constituída por uma camada paliçádica lignificada; em M. bella, depositamse espessamentos em forma de ¿U¿, e em C. pubescens, origina-se uma camada de esclereídes. As células mesotestais de E. punicifolia apresentam espessamentos secundários; em M. bella e C. pubescens, elas permanecem sem lignificação e são comprimidas tangencialmente. No embrião da semente madura, diferenciam-se idioblastos fenólicos e depositam-se grãos de amido nas três espécies e cavidades secretoras subepidérmicas em E. punicifolia e M. bella. Os caracteres seminais também seguiram os já descritos para os gêneros
Abstract: The Brazilian cerrado has been devastated and the structural aspects of the plants in this biome have been scarcely investigated considering its great diversity. In literature, there are no studies about the reproductive structures of the majority of the indigenous species of Myrtaceae, one of the most representative of the Brazilian flora and cerrados. Analyses of fruits and seeds are limited to economically important species and rarely include anatomical and ontogenetic aspects. The present work aimed at detailing and comparing the morphology and ontogenesis of the fruits and seeds of Eugenia punicifolia, Myrcia bella and Campomanesia pubescens, three species commonly found at cerrado sensu lato. Material was processed according to standard anatomical techniques for inclusion in plastic resin. In all three species, both in the ovarian wall and in the pericarp, there were a fundamental region, which was divided into three areas; a great number of cells with phenolic content; and secretory cavities with lipidic content. Ovules were campylotropous; in E. punicifolia, chalaza was extensive; in the remaining species, chalaza was less extensive. In the beginning of the fruits development, intense mitotic activity was noticed in all regions of the fruits. There were intercellular spaces in the mesocarp of E. punicifolia and M. bella as well as differentiated and isolated sclereids in the mesocarp and concrescence of the most inner layers of the mesocarp and endocarp with the seminal tegument of C. pubescens. The mesocarpic cells of mature fruits elongated radially, originating the fleshy pulp in all three species. E. punicifolia and M. bella presented very similar pericarp development; C. pubescens showed particular characteristics, following the pattern already described for its genus. During seminal development, more intense growth occurred in the anti-raphe region, originating reniform seeds. In Eugenia punicifolia, chalaza expanded, making evident the pachychalazal development of the seed. Perichalaza was formed in M. bella. In C. pubescens, chalaza expansion was restricted to the hilum. Exotesta cells elongated radially. Cell divisions increased the number of layers of mesotesta, which was phenolic all over the seminal involucrate in E. punicifolia and M. bella. The testa inner epidermis and the inner tegument did not show any alterations. The embryonic axis of E. punicifolia was short and continuous to the thick and partially concrescent cotyledons; those of M. bella and C. pubescens were very elongated. In M. bella, two twisted foliaceous cotyledons were identified. In C. pubescens, cotyledons were extremely small and could not be found anatomically. Mature seeds were campylotropous. The exotesta of Eugenia punicifolia had a lignified palisadic layer. In M. bella, ¿U¿-shaped thicknesses were noticed, and sclereids layers were observed in C. pubescens. Mesotestal cells of E. punicifolia showed secondary thicknesses; those of M. bella and C. pubescens did not show lignification and were tangentially compressed. In the embryo of the mature seed, differentiated phenolic idioblasts were observed as well as deposits of amid granules in all three species and subepidermic secretory cavities in E. punicifolia and M. bella. Seminal characters also followed the pattern already described for their genera
Mestrado
Mestre em Biologia Vegetal
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Coneglian, Inara Regiane Moreira [UNESP]. "Morfoanatomia de ovário, pericarpo e semente de sete espécies de Myrteae DC. (Myrtaceae)." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/104003.
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coneglian_irm_dr_botib.pdf: 1880517 bytes, checksum: 8f54e43516be2d23550fba138b8614d6 (MD5)Myrtaceae é uma das mais relevantes famílias da flora brasileira. Foi tradicionalmente dividida em duas subfamílias, Myrtoideae, com frutos carnosos, e Leptospermoideae, com frutos secos. Esta classificação vem sendo questionada e estudos moleculares atuais vêm reorganizando a família; a classificação mais recente divide a família em Myrtoideae e Psiloxyloideae, sendo que todas as espécies nativas do Brasil encontram-se em Myrteae. Dentro de Myrteae, trabalhos clássicos reconhecem três subtribos, distintas com base na morfologia do embrião e nas características do tegumento seminal, Eugeniinae, Myrciinae e Myrtinae; no cerrado sensu stricto da região de Botucatu, há representantes destas três subtribos. Atualmente, reconhecem-se espécies cuja posição nas subtribos é indefinida, caso de Blepharocalyx salicifolius. Apesar de sua importância taxonômica, os órgãos reprodutivos de Myrtaceae ainda são pouco conhecidos e poderiam fornecer informações relevantes para a compreensão da evolução dos caracteres nos grupos infrafamiliares. Estudos envolvendo a ontogênese de tais órgãos são ainda mais raros, e estudos ontogenéticos que busquem diferenças no desenvolvimento entre estados de caráter aparentemente idênticos com origens independentes, caso dos frutos carnosos, podem fornecer novas informações, passíveis de aplicação em classificações infrafamiliares. Desta forma, sete espécies de Myrteae tiveram seus órgãos reprodutivos analisados anatomicamente, fazendo-se uso de técnicas usuais de anatomia vegetal, com relação aos seguintes aspectos: 1) Vascularização do ovário de botões florais, a fim de se definir o tipo de ovário ínfero e de se reconhecerem possíveis características utilizáveis em estudos filogenéticos; 2) Desenvolvimento dos pericarpos, procurando...
Myrtaceae is one of the most relevant families of the Brazilian flora. It was traditionally divided into two subfamilies, Myrtoideae, with fleshy fruits, and Leptospermoideae, with dry fruits. This classification has been questioned and current molecular studies have been reorganizing the family; the most recent classification has divided the family into Myrtoideae and Psiloxyloideae, and all species native to Brazil are included in Myrteae. Considering Myrteae, classic studies have recognized three subtribes that are different based on the embryo morphology and on the seed coat features, Eugeniinae, Myrciinae and Myrtinae; in sensu stricto cerrado in the region of Botucatu, there are representatives of these three subtribes. Currently, species with undefined position in the subtribes, such as Blepharocalyx salicifolius, have been recognized. Although taxonomically important, the reproductive organs of Myrtaceae are still little known and could yield relevant information to understand the evolution of traits in infrafamilial groups. Studies involving the ontogeny of such organs are even scarcer, and ontogenetic studies searching for development differences between character states apparently identical with independent origins, such as fleshy fruits, may provide new information that could be applied in intrafamilial classifications. Thus, seven Myrteae species had their reproductive organs anatomically analyzed by adopting usual techniques of plant anatomy for the following aspects: 1) Vasculature of the ovary of floral buds, to define the type of inferior ovary and to recognize characters that may be used in phylogenetic studies; 2) Pericarp development, attempting to recognize phases and/or traits that may be used in phylogenetic studies; 3) Seed development, attempting to recognize differences that... (Complete abstract click electronic access below)
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Lemmons, Justin M. "Nutrient Availability Affects Flowering Rate but has Limited Influence on Morphology of the Hooded Pitcher Plant, Sarracenia minor." UNF Digital Commons, 2013. http://digitalcommons.unf.edu/etd/475.
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Carnivorous plants perform as both producers and consumers. Botanical carnivory has evolved in sunny, moist, nutrient-poor environments, and the primary nutrient supplied by prey is proposed to be nitrogen. There is a trade-off between carnivorous and photosynthetic structures which corresponds to degree of carnivory expression and available nutrients. This study was conducted on the hooded pitcher plant, Sarracenia minor, which is a facultative wetland plant and Florida-threatened species. Sarracenia minor is considered a specialist myrmecophage and ants characterize the majority of attracted and captured prey. Ants not only provide nutritional benefit, but also protection against herbivory. A natural population of S. minor in northeast Florida was selected to test response to prey and fertilizer nitrogen in a press-experimental design. Introduced fire ants (Solenopsis invicta) and ammonium nitrate (NH4NO3) were used as prey and fertilizer nitrogen sources, respectively. Treatments included: 1) ant addition; 2) fertilizer addition; 3) ant addition/fertilizer addition; 4) no ants/no fertilizer; 5) control. Treatments were administered biweekly and morphological characteristics and herbivory were measured monthly from April-November 2012. Results indicated no significant treatment effects on plant performance and morphological characteristics, except for a significantly greater number of flowers displayed by the nutrient-deprived group (p < .005). Herbivory by Exyra semicrocea also showed a marginally significant negative effect on the tallest pitchers per ramet. Since nitrogen is primarily stored by pitchers and allocated to new growth in the following growing season, the predictive power of this study may be limited. However, increased flowering rate in the nutrient-deprived group suggests that plants were induced to flower from nutrient stress. Also, a burn at the beginning of the study likely influenced nutrient availability and plant response to experimental treatments. In conclusion, stress may have occurred from both fire and nutrients, and S. minor showed resistance and poor response to nitrogen addition.
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Gray, Brandan L. "Ecology, Morphology, and Behavior in the New World Wood Warblers." Ohio University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1565180087270449.
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Cosme, Marco Paulo Rebeca. "Effects of interaction between arbuscular mycorrhizal fungi, rhizobacteria, soil phosphorus and plant cytokinin content on tobacco growth." Master's thesis, ISA, 2010. http://hdl.handle.net/10400.5/15193.
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Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de AgronomiaA rizosfera é uma zona importante em termos de actividade e diversidade microbiana, onde ocorrem associações benéficas entre plantas e microorganismos, e é fundamental na produção agrícola. Ao proliferarem num meio complexo e heterogéneo como o solo, as raízes desenvolvem-se de forma estruturada, mas flexível, por forma a optimizar suas funções. Factores endógenos, como fisiologia e genética da planta, bem como factores exógenos abióticos e bióticos são elementos determinantes. Neste estudo proponho testar a hipótese de que os efeitos dos microorganismos do solo sobre o crescimento da planta estão associados a efeitos sobre a morfologia radicular e dependentes dos níveis endógenos de fitohormonas e disponibilidade de nutrientes no solo. Uma experiência factorial foi instalada na estufa, com a presença ou ausência de Glomus intraradices ou Pseudomonas fluorescens, com dois regimes de fertilização de fósforo, e com a linhagem selvagem de tabaco (Nicotiana tabacum) ou a transgénica 35S:CKX2 com teor de citoquinina reduzido. Os efeitos dos microorganismos sobre a biomassa alternaram entre o negativo, neutro ou positivo, dependendo da linhagem, do regime de fertilização e a presença de microorganismos, e explicam-se parcialmente com alterações na morfologia da raiz. A micorrização aumentou na linhagem 35S:CKX2 ou em presença de P. fluorescens-------------------------------------------------ABSTRACT - The rhizosphere is an important zone for microbial activity and diversity, where several beneficial associations between roots and microorganism occur, and is fundamental in terms of defining terrestrial food production. When growing in a complex and heterogeneous medium such as soil, roots develop in a structured but flexible manner to optimize their functions. Endogenous factor, such as plant physiology and genetics, as well as abiotic and biotic exogenous factors are important determinants. In the present study I hypothesized that the effects of soil microorganisms on root morphology are associated with plant growth and differ depending on endogenous phytohormone levels and soil nutrient availability. A full factorial experiment was set up in the greenhouse, with presence or absence of Glomus intraradices or Pseudomonas fluorescens, with two phosphorus amendments, and with the tobacco wild type (Nicotiana tabacum) or the 35S:CKX2 transgenic line with reduced cytokinin content. The effects of microorganisms on plant biomass changed from negative to neutral and positive depending on plant type, phosphorus amendment and microorganism presence, and are partially explained by alteration on root morphology. Mycorrhization was enhanced in the 35S:CKX2 mutant or in presence of P. fluorescens
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Buchman, Natalie L. "Influences of Pea Morphology and Interacting Factors on Pea Aphids (Acyrthosiphon pisum)." Ohio : Ohio University, 2008. http://www.ohiolink.edu/etd/view.cgi?ohiou1218819576.
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Heinken, Thilo, Marcus Schmidt, Goddert von Oheimb, Wolf-Ulrich Kriebitzsch, and Hermann Ellenberg. "Soil seed banks near rubbing trees indicate dispersal of plant species into forests by wild boar." Universität Potsdam, 2006. http://opus.kobv.de/ubp/volltexte/2010/4647/.
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Current knowledge about processes that generate long-distance dispersal of plants is still limited despite its importance for persistence of populations and colonization of new potential habitats. Today wild large mammals are presumed to be important vectors for long-distance transport of diaspores within and between European temperate forest patches, and in particular wild boars recently came into focus. Here we use a specific habit of wild boar, i.e. wallowing in mud and subsequent rubbing against trees, to evaluate epizoic dispersal of vascular plant diaspores. We present soil seed bank data from 27 rubbing trees versus 27 control trees from seven forest areas in Germany. The mean number of viable seeds and the plant species number were higher in soil samples near rubbing trees compared with control trees. Ten of the 20 most frequent species were more frequent, and many species exclusively appeared in the soil samples near rubbing trees. The large number of plant species and seeds – approximated > 1000 per tree – in the soils near rubbing trees is difficult to explain unless the majority were dispersed by wild boar. Hooked and bristly diaspores, i.e. those adapted to epizoochory, were more frequent, above that many species with unspecialised diaspores occurred exclusively near rubbing trees. Different to plant species closely tied to forest species which occur both in forest and open vegetation, and non-forest species were more frequent near rubbing trees compared with controls. These findings are consistent with previous studies on diaspore loads in the coats and hooves of shot wild boars. However, our method allows to identify the transport of diaspores from the open landscape into forest stands where they might especially emerge after disturbance, and a clustered distribution of epizoochorically dispersed seeds. Moreover, accumulation of seeds of wetness indicators near rubbing trees demonstrates directed dispersal of plant species inhabiting wet places between remote wallows.Das aktuelle Wissen über Prozesse, die zur Fernausbreitung von Pflanzen führen, ist trotz ihrer Bedeutung für das Überleben von Populationen und die Besiedlung neuer potenzieller Habitate noch immer sehr begrenzt. Wildlebende Großsäuger sind heutzutage vermutlich wichtige Vektoren für den Ferntransport von Diasporen innerhalb und zwischen den einzelnen Waldflächen in Mitteleuropa, und speziell das Wildschwein (Sus scrofa L.) spielt dabei offenbar eine herausragende Rolle. Wir nutzen hier ein spezifisches Verhalten des Wildschweins – Suhlen im Schlamm und nachfolgendes Scheuern an sogenannten Malbäumen – um die epizoochore Ausbreitung von Gefäßpflanzen-Diasporen einzuschätzen. Dargestellt werden die Ergebnisse von Samenbank-Untersuchungen von 27 Malbäumen im Vergleich zu 27 Kontrollbäumen aus sieben Waldgebieten in Deutschland. Sowohl die mittlere Zahl lebensfähiger Samen als auch die Artenzahl waren höher in Bodenproben neben Malbäumen. Zehn der 20 in der Samenbank verbreitetsten Pflanzenarten hatten hier ihren Schwerpunkt, und viele Arten kamen ausschließlich in den neben Malbäumen gewonnenen Proben vor. Die große Zahl von Pflanzenarten und Samen – zumindest > 1000 pro Baum – im Boden an Malbäumen lässt sich nur durch die Aktivität der Wildschweine erklären. Mit Haken oder Borsten ausgestattete, d.h. an Epizoochorie angepasste Diasporen waren häufiger, aber auch viele Arten mit unspezialisierten Diasporen kamen ausschließlich in der Samenbank bei Malbäumen vor. Anders als weitgehend an Wald gebundene Pflanzenarten waren solche, die sowohl im Wald und im Offenland vorkommen, sowie nicht im Wald vorkommende Arten häufiger neben Malbäumen als neben Kontrollbäumen. Diese Befunde stimmen mit denen früherer Untersuchungen von Diasporenladungen im Fell und in den Hufen geschossener Wildschweine überein. Unsere Methode erlaubt darüber hinaus aber die Identifizierung des Diasporentransports aus dem Offenland in die Waldbestände, wo sie insbesondere nach Störungen keimen dürften, sowie einer ungleichmäßigen Verteilung epizoochor ausgebreiteter Diasporen. Außerdem zeigt die Akkumulation von Samen von Nässezeigern neben den Malbäumen eine gezielte Ausbreitung nasse Standorte bewohnender Pflanzenarten zwischen entfernt gelegenen Suhlen.
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Gonzalez, Eugenia. "Characterization of isolates of Glomerella cingulata causal agent of Glomerella leaf spot and bitter rot of apples based on morphology and genetic, molecular, and pathogenicity tests." NCSU, 2003. http://www.lib.ncsu.edu/theses/available/etd-10302003-213733/.
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Isolates of Glomerella cingulata, Colletotrichum gloeosporioides and C. acutatum, obtained from symptomatic fruit and leaves collected from apple orchards in the US and Brazil, were characterized based on morphological and cultural characteristics, vegetative compatibility groups (VCGs), mtDNA RFLP haplotypes, and the sequence analysis of a 200 bp intron of the glyceraldehyde 3-phosphate dehydrogenase (GDPH) gene. The isolates were also tested for pathogenicity on leaves and fruit. The population structure of the species associated with bitter rot of apples in two orchards of cv. Granny Smith was also studied. Multiple VCGs and mtDNA RFLP haplotypes were found within each of the species tested. Phylogenetic trees constructed based on Neighboring-Joining and Maximum Parsimony methods, using the intron sequence, produced similar topologies. Each species was separated into distinct groups. All isolates tested were pathogenic on fruit. Only isolates with haplotypes G1, G1.1, G3, and G4 and VCGs 1, 4, and 5 were capable of causing Glomerella leaf spot (GLS). G. cingulata was the predominant species associated with bitter rot in the two orchards of cv. Granny Smith. Vegetative compatibility was a better indicator than molecular characterization for distinguishing isolates of G. cingulata pathogenic on both leaves and fruit from the ones pathogenic only on fruit. Isolates of G. cingulata from the US and Brazil which cause GLS were included in different haplotypes and phylogenetic groups. Therefore, our results suggest that isolates of G. cingulata from the US capable of causing both GLS and bitter rot arose independently of Brazilian isolates of G. cingulata, and may have arisen from isolates of G. cingulata from the US that originally were capable of causing bitter rot only. Slower growth, lower optimum growth temperature, and less sensitivity to benomyl distinguished isolates of C. acutatum from isolates of G. cingulata and C. gloeosporioides.
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Mfeka, Nonkululeko. "Morphology and mineral content of cowpea lines in response to planting date and zinc application rate." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2672.
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Thesis (MTech (Agriculture))--Cape Peninsula University of Technology, 2017.Cowpea (Vigna unguiculata (L.) Walp) is an important grain and fodder legume grown around the world. It is a dual purpose grain legume crop, providing food for man and livestock. Cowpea is identified as a potential crop to diversify food production, minimize production input by improving soil fertility and improve micronutrients of seed, therefore, improving human nutrition. There is limited information available on cowpea production and suitable agronomic practices including planting date to best suit different environmental conditions in South Africa. The objective of this study was therefore to i) evaluate two soil types (sandy and clay soil) and its effect on cowpea, yield components and mineral composition, ii) the effect of different planting date and iii) assess the effect of zinc fertilizer application rate on vegetative, reproductive parameters and mineral content of cowpea seed. A field trial was conducted in Agricultural Research Council (ARC), in two locations Nietvoorbij (clay loam soil) and Bien Donne’ (sandy soil) during the 2015 summer planting season. The trial layout was conducted in a randomised complete block design (RCBD) with five replicates. The factors of the study include three cowpea lines: Cowpea Veg1, M217 and Qukawa with zinc application rate of (0, 15 and 30 kg/ha) through soil application and two planting date (2 October and 2 November 2015). The following agronomic variables were collected, in both locations: germination rate, number of leaves, number of branches, plant height, number of seed per pod, number of pods per plant, pod length, pods per treatment, pod weight, 100 seed weight, morphological traits, moisture content and seed mineral content. Vegetative data was collected on a fourth-night basis on six middle plants per treatment and reproductive parameters were taken after harvest. The variables were subjected to ANOVA using software SAS (2012). Treatments were tested at 5% level of significance and differences between treatments were separated using LSD and DMRT of the SAS 2012 test. The results indicated that vegetative and reproductive parameters measured varied significantly among cowpea lines in each location and across locations due to different cowpea lines and soil type. Line Cowpea Veg1 and Qukawa were the best performing line in both vegetative and yield parameters across the two planting dates in 2015. These lines significantly obtained higher plant height than line M217. Yield and yield parameters were significantly affected by cowpea line. Qukawa obtained the highest seed yield at Bien Donne’ with a mean of 1184.2 kg/ha and seed yield of 686.25 kg/ha for Cowpea Veg1 at Nietvoorbij. The second planting date (2 November 2015) improved germination of plants across the two locations, therefore improving vegetative growth. Zinc (Zn) fertilizer significantly improved plant height across all treatments. An inconsistent response to yield parameters due to Zn application rate was observed. However, though not significant, Zn application of 15 kg/ha increased most of the measured parameters. It was concluded that line Cowpea Veg1 and Qukawa were the best performing lines. The second planting date (2 November) increase germination rate for both locations. It is therefore, recommended that future research should evaluate Zn fertilizer time of application.