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Dissertations / Theses on the topic 'Crop storage'
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Subedi-Chalise, Kopila. "Impacts of Crop Residue and Cover Crops on Soil Hydrological Properties, Soil Water Storage and Water Use Efficiency of Soybean Crop." Thesis, South Dakota State University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10265200.
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<p> Cover crops and crop residue play a multifunctional role in improving soil hydrological properties, soil water storage and water use efficiency (WUE). This study was conducted to better understand the role of crop residue and cover crop on soil properties and soil water dynamics. The study was conducted at the USDA-ARS North Central Agricultural Research Laboratory, located in Brookings, South Dakota. Two residue removal treatments that include low residue removal (LRR) and high residue removal (HRR) were established in 2000 with randomized complete block design under no-till corn (Zea mays L.) and soybean (Glycine max L.) rotation. In 2005, cover crop treatments which include cover crops (CC) and no cover crops (NCC) were integrated into the overall design. Soil samples were collected in 2014, 2015 and 2016. Data from this study showed that LRR treatment resulted in lower bulk density (BD) by 7 and 9% compared to HRR in 2015 and 2016, respectively, for 0-5 cm depth. Similarly, LRR treatment significantly reduced soil penetration resistance (SPR) by 25% in 0-5 cm depth compared with HRR treatment. In addition to this, LRR treatment significantly increased soil organic carbon (SOC) concentrations and total nitrogen (TN) by 22 and 17%, respectively, in 0-5 cm. Similarly, CC treatment resulted in lower BD and SPR by 7% and 23%, respectively, in 0-5 cm depth in 2015 compared with NCC treatment. The LRR significantly increased soil water infiltration by 66 and 22% compared to HRR in 2014 and 2015, respectively. Similarly, the CC treatment significantly increased infiltration by 82 and 22% compared to the NCC in 2014 and 2015, respectively. The significant impact of a crop residue was observed on soil water retention (SWR) in 2014 and 2015 for the 0-5 cm depth. The LRR and CC treatments increased the soil volumetric moisture content (VMC) and soil water storage (SWS) on the surface 0-5 cm depth. However, the trend was not always significant during the growing season. The CC treatment significantly impacted the soybean yield by 14% and WUE by 13% compared with NCC treatment. Some interaction of residue by cover crops was observed on BD, SPR, VMC, and SWS, which showed that the use of cover crops with LRR can be beneficial in improving the soil properties.</p>
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Ameobi, John Babatope. "Maize drying with ambient air." Thesis, University of Newcastle Upon Tyne, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386835.
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Zhang, Yuhua. "Genetic manipulation of seed storage protein and carbohydrate metabolism in barley (Hordeum vulgare L.)." Thesis, University of Nottingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368346.
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Thornton, M. S. "Investigations into the problems associated with the development of naked oats as a crop." Thesis, Aberystwyth University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325023.
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Gan, G. "Heat and moisture transfer in deep bed cooling of grain and vegetables." Thesis, University of Newcastle Upon Tyne, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234390.
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Guntrip, John. "Variation and covariation in and between life-history traits of the larger grain borer, Prostephanus truncatus (Coleoptera, Bostrichidae), : and the cowpea weevil, Callosobruchus maculatus (Coleoptera, Bruchidae), with particular reference to trade-offs." Thesis, University of Reading, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259509.
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Makhamad, Basira Mir. "Seeds can speak: functional roles of structures from Early Bronze Age Ib through archaeobotanical investigation at Arslantepe (Turkey)." Master's thesis, Universidade de Évora, 2019. http://hdl.handle.net/10174/28565.
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This thesis illustrates the results of the archaeobotanical study carried out at the long-lived site of Arslantepe (Malatya), Turkey. The study focusses on 131 carpological samples from the village of the Early Bronze Age (VIB2 period, 3100-2900 cal. BCE) destroyed by a fire. The aim of this study was to shed light on the functional roles of structures from Early Bronze Age Ib using plant remains. 63,941 seeds/fruits, including the estimated ones, have been analyzed. This study has identified 15 taxa belonging to 7 plant families. Cultivated species were found together with wild plants and non-economic weeds. The distribution of plant remains in the rooms allows to find out that Building IX inhabitants were mainly specialized in cereal production. This building has been used for crop processing, storing and food consumption. While Building VIII was not a place where crop processing had been practiced. As regards an isolated room A472, inhabitants of this room cultivated not only cereals but also legumes. Based on results, agriculture at Arslantepe was family based.
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Martin, Benjamin A. "TWO ESSAYS ON WHOLE FARM MODELING AND CROP MARKETING IN WESTERN KENTUCKY." UKnowledge, 2018. https://uknowledge.uky.edu/agecon_etds/65.
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This thesis is composed of two essays that investigate whole farm planning and crop marketing in western Kentucky. In the first essay, contracting decisions between food corn producers and a mill are analyzed to observe factors affecting the bushel amount farmers contract. Unbalanced panel data containing seven years’ worth of pricing and contract information are used with a fixed-effects model to generate parameter estimates and quantify their effect on bushels contracted. It was found that contract attributes, market condition, and relationship-specific assets had a significant effect on producers’ food corn contracting decisions. The second essay utilizes mixed-integer programming to optimize resource allocation and marketing strategy for a hypothetical farm. Post-optimal analysis is performed to determine non-binding capacities for drying and storage equipment. The model is re-run with these non-binding capacities to observe changes in net returns as well as planting, harvesting, and marketing strategies. New equipment and associated costs are identified, and the change in net returns from the base case is used as net cash flow in a net present value investment analysis. Results of the investment analysis indicate increasing drying and storage capacity is a wise investment given the scenario modeled.
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Hilli, A. (Anu). "The effect of crop quality and pre-treatment on germination in Scots pine and Norway spruce seeds." Doctoral thesis, University of Oulu, 2009. http://urn.fi/urn:isbn:9789514290121.
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Weather conditions during the growing season are determining the size and quality of the Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) seed crop in northern areas. Pathogens, fungi, and insects also have an effect on seed crops. The varying quality of seeds from forest stands and seed orchards does not full fill the germination requirements of tree nurseries. Multi-phase pre-treatment are therefore used in forest tree seed centres to improve seed lots quality.
The main objectives of this study were to analyse long-term variation in the size and quality of Scots pine seed crops in Northern Finland. Determine the impact of fungal injuries on the structures of Norway spruce seeds. To detect changes in the germination capacity and rate of Norway spruce seeds during pre-treatment phases and to determine the impacts of short-term and long-term storage on the germination of treated seeds.
The study found that in most years, regeneration of Scots pine in Northern Finland is limited by quantity as well as quality the seed crop. The long-term average of the Scots pine seed crop was 77seeds/m2 and the long-term average expected germination percentage was 61%. Aeciospores of the inlad spruce cone rust Chrysomyxa pirolata (Körnicke) Wint. were found to form inside Norway spruce seeds, destroying the nucellar layers and reducing germination of seeds. In general, the germination capacity and rate of Norway spruce seeds increased during pre-treatment phases. The germination capacity of seeds increased about 30% and the rate by more than 40% during pre-treatment. During long-term storage the germination capacity and rate of pre-treated Scots pine seeds were preserved better in frozen storage than in cool storage. It was found that pre-treated Scots pine forest stand seeds can be stored for several years in frozen conditions. The germination capacity and rate of pre-treated orchard seeds were effected significantly more than those from forest stands. It is therefore recommended that Scots pine seeds from orchards be stored without pre-treatment. The germination capacity and rate of treated Norway spruce seeds from orchards was not significantly different after one year of storage.
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Mense, Andrew Lawrence. "Effects of aging new crop wheat and whole wheat flour on breadmaking quality and glycolipid composition." Thesis, Kansas State University, 2012. http://hdl.handle.net/2097/15076.
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Master of Science<br>Department of Grain Science and Industry<br>Jon Faubion<br>Whole wheat flour has become a popular ingredient in baked goods. Consumers are seeking the added benefits of consuming healthy phytochemicals and bioactive compounds. As the demand for wholemeal flour increases it is important to understand the factors contributing to changes in whole wheat flour breadmaking quality as a function of both wheat and flour age. In wholemeal flour, the lipid composition appears to be a factor causing variable baking quality. Changes that occur in both freshly harvested wheat and milled flour can cause variations in baking quality. Bakers’ attempts to adjust formulations and processes are often unsuccessful. The objective of this study was to determine the effects of aging both new crop wheat and freshly milled flour at 2 different temperatures on baking quality and glycolipid composition. This study aged freshly harvested Overley hard red winter wheat at RT (23˚C) and FZ (-26˚C) for 8, 50, and 91 days before milling. Whole wheat flour baking and lipid extraction studies were performed incrementally over 31 days of flour storage after each milling. Glycolipid structure and amounts were measured using automated electrospray ionization-tandem mass spectrometry. The glycolipids analyzed in this study were DGDG (digalactosyldiglycerol), MGDG (monogalactosylmonoglycerol), MGMG (monogalactosylmonoglycerol), and DGMG (digalactosylmonoglycerol). Both the wheat and flour stored at -26˚C produced larger mean loaf volumes than did the 23˚C treatment for all 3 wheat ages. The FZ and RT DGDG:MGDG ratios were similar over both wheat and flour age so changes to the glycolipid fraction did not appear to be the cause of the significant difference between volumes of bread baked from samples stored at RT and FZ. There was limited change in mean volume over flour age except for an increase at the FZ 91 day point. The DGDG:MGDG ratios were generally unchanged over flour age. Loaf volumes were the same over wheat age except for an unexpected drop during the 50 day wheat study. The corresponding DGDG:MGDG ratios did not show any significant differences over wheat age. The FZ storage temperature might be inhibiting some biochemical change not affecting the glycolipids, leading to higher volumes than the RT storage treatment.
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Lea, Krista La Moen. "TALL FESCUE ERGOVALINE CONCENTRATION BASED ON SAMPLE HANDLING AND STORAGE METHOD." UKnowledge, 2014. http://uknowledge.uky.edu/pss_etds/35.
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Ergovaline is produced by the endophyte Neotyphodium coenophialum (Morgan-Jones and Gams) in tall fescue (Schedonorus arundinacea (Schreb.) Dumort. = Festuca arundinacea Schreb.) and is blamed for a multitude of costly livestock disorders. Testing of pastures is common in both research and on farm situations. Since ergovaline is known to be unstable and affected by many variables, the objective of this study was to determine the effect of sample handling and storage on the stability of this compound. Homogeneous milled tall fescue sub-samples were analyzed for ergovaline concentration using HPLC after a range of sample handling procedures or storage. Ergovaline was unstable in milled material after 24 hours in storage, regardless of temperature. The decrease in ergovaline after 24 hours ranged from 17 to 60%. These results show that tall fescue sample handling and storage have a significant effect on ergovaline concentrations. In conclusion, accurate laboratory analysis of ergovaline content may require that samples be transported immediately to the laboratory on ice for immediate analysis. Most laboratories are not equipped for same day analysis, therefore researchers and producers should acknowledge that laboratory ergovaline results may be lower than the actual content in the field.
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Fehervari, Gabor. "The factors affecting the timing and volume of sales in Hungarian farmers' crop marketing decisions : an alternative perspective on the theory of price of storage." Thesis, University of Reading, 2017. http://centaur.reading.ac.uk/75020/.
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The existence of convenience yield has become an axiom in the analysis of intertemporal price relations for commodities. However, the link between the macro level convenience yield concept and the micro-level sell/store decisions of stock holders lacks empirical evidence. The main objective of the study is to establish the drivers behind timing and volume of stock holders' actual commodity sales and to establish whether the decision-making process can be linked to convenience yield. Regression analysis of intertemporal price spreads, monthly dummies and stocks for Hungarian com are performed both to establish the relevance of the convenience yield concept, and to confirm its relationship to stocks. The GSADF (Generalized Sup-ADF) method is applied on consecutive expiries of corn futures, in order to validate convenience yield related assumptions of explosiveness. An alternative explanation of the convenience yield concept formulated in the spatial-temporal interpretation of storage is also tested on a large volume of actual Hungarian com logistics data. Finally, a choice model with hypothetical sales scenarios, filled by a large sample of Hungarian farmers is performed in order to validate whether a two-step Heckman model offers a good approximation of the actual decision-making process behind stock sales. Both convenience yield's existence and its inverse relation to stocks are demonstrated for Hungarian com. However, evidence does not support the hypothesis that nearby prices show greater tendencies for bubble formation than later expiries. Contrary to expectations, spatial¬temporal storage conclusions are validated on Hungarian corn, as delivery distance to central markets does increase through the season. Some variables proposed are found to be individually significant in driving stock sales, and the expectation that selling is best explained by a two-step Heckman model is also partly confirmed. Besides testing existing models on the data of a new geography, it is the additional step taken towards real decision-makers, where this study of commodity sales is expected to contribute both to convenience yield theory and to our current knowledge of how the physical grain markets work.
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Munhuewyi, Karen. "Postharvest losses and changes in quality of vegetables from retail to consumer : a case study of tomato, cabbage and carrot." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71946.
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Thesis (MScFoodSc)--Stellenbosch University, 2012.<br>ENGLISH ABSTRACT: Postharvest losses of three different vegetables (tomato - a fruit, cabbage - a leaf and carrot - a root vegetable) were investigated directly after retail purchasing and during consumer simulated storage. To conduct this study, three retail outlets (2 supermarkets and an outdoor market) were selected in Stellenbosch, South Africa. Retail prices of each vegetable were recorded from each respective Outlet. Surrounding environmental conditions (air temperature and relative humidity) at retail and during simulated consumer storage were also monitored. Vegetable postharvest losses were determined by quantifying the incidence of physical loss and changes in physico-chemical properties (colour, firmness, weight loss, ascorbic acid, total pigments, total soluble solids, titratable acid and proximate composition) over time. The percentage losses observed were then used to estimate the associated economic and environmental resource impacts of postharvest vegetable losses at the national level.
Vegetable losses immediately at retail purchase were 14.56%, 21.21% and 17.93% for tomato, cabbage and carrot, respectively. The estimated combined volume lost for all three vegetables at national level was approximately 26 460 t valued at R33.70 million. Overall economic loss was highest for tomatoes and least for carrots. The magnitude of the losses observed differed for all the outlets. Vegetable losses were mostly high for the produce from the outdoor market compared to the supermarkets during storage. Throughout the whole trial, mechanical damage accounted for at least 50 to 70% of the losses while the remainder was due to decay and insect damage. Post retail storage temperature; ambient (22–25ºC) vs. cold store (0ºC and 10–12 ºC) had a significant (P<0.05) effect on the vegetable losses. This was for both quantitative and qualitative attributes. Losses for tomato and cabbage were 18.52% and 16.67% after 3 days while carrot losses were 11.83% at 7 days after having been kept in the recommended respective cold storage temperatures. Ambient storage losses were also lowest for carrots at 22.53% after 7 days, while tomato and cabbage losses stood at 24.27% and 34.34% after 3 days of storage, respectively. Vegetable firmness generally decreased while weight loss increased with storage time. Colour development increased favourably at ambient temperature for the tomato whereas for cabbage and carrot better colour retention was observed in the cold storage. Chemical changes for all three vegetables were also most pronounced at ambient temperature with significant (P<0.05) losses observed for ascorbic acid. Changes were also noted for total pigments, soluble solids and acidity, however there was no common significant trend for all three vegetables.
Estimates of carbon dioxide emissions reveal that postharvest vegetable losses contribute to unwarranted emissions of at least 1.37 – 13.77 million tonnes of carbon dioxide equivalents (CO2eq.) at the national level. The losses are also accompanied by wastage of approximately 3.74 – 4.35 million m3 of fresh water as well as 14.79 – 111.63 million MJ of fossil energy. The vegetable with highest production volumes and retail price was the tomato and accordingly, its postharvest losses had the severest environmental and resource impacts.<br>AFRIKAANSE OPSOMMING: Die ná-oes-verliese van drie verskillende groentes (tamatie – 'n vrug, kool – 'n blaar, en wortel – 'n wortelgroente) is direk ná kleinhandelaankope en tydens gesimuleerde verbruikersberging ondersoek. Ten einde hierdie studie uit te voer, is drie kleinhandelsafsetpunte (twee supermarkte en 'n opelugmark) in Stellenbosch, Suid-Afrika gekies. Die kleinhandelpryse van elke groente van die drie onderskeie afsetpunte is opgeteken. Omliggende omgewingstoestande (lugtemperatuur en relatiewe humiditeit) tydens verkope en gesimuleerde verbruikersberging is ook gemonitor. Die ná-oes-verliese van die groentes is bepaal deur die voorkoms van fisiese verlies en veranderings in fisio-chemiese eienskappe (kleur, fermheid, gewigsverlies, askorbiensuur, totale pigmente, totale oplosbare suikers, titreerbare suur en algemene samestelling) met verloop van tyd te versyfer. Die waargenome persentasie verliese is gebruik om die geassosieerde ekonomiese en omgewingshulpbron-impak van ná-oes-groenteverliese op nasionale vlak te beraam.
Groenteverliese met kleinhandelaankope was onderskeidelik 14.56%, 21.21% en 17.93% vir tamaties, kool en wortels. Die beraamde saamgestelde volume verlies vir al drie groentes op nasionale vlak was ongeveer 26 460 t, met 'n waarde van R33.70 miljoen. Die algehele ekonomiese verlies was die hoogste vir tamaties en die laagste vir wortels. Die omvang van die waargenome verliese het vir al die afsetpunte verskil. Groenteverliese tydens berging was hoofsaaklik hoog vir die produkte van die opelugmark in vergelyking met dié van die supermark. Tydens die algehele proefneming was meganiese skade verantwoordelik vir ten minste 50 tot 70% van die verliese, terwyl die res aan verrotting en insekskade toegeskryf kan word. Bergingstemperatuur ná kleinhandelaankope: omgewingstemperatuur (22 – 25 ºC) vs. koue berging (0 ºC en 10–12 ºC) het 'n beduidende (P < 0.05) uitwerking op groenteverlies gehad. Dit geld vir sowel kwantitatiewe as kwalitatiewe attribute. Verliese vir tamaties en kool was onderskeidelik 18.52% en 16.67% ná drie dae, terwyl dit vir wortels 11.83% teen sewe dae was nadat dit teen die aanbevole onderskeie koue bergingstemperature geberg is. Bergingsverliese in omgewingstemperatuur was ook die laagste vir wortels teen 22.53% ná sewe dae, terwyl die verlies van tamaties en kool onderskeidelik 24.27% en 34.34% was ná drie dae se berging. Die fermheid van die groente het oor die algemeen met die duur van berging verminder, terwyl gewigsverlies toegeneem het. Kleurontwikkeling het gunstig teen omgewingstemperatuur toegeneem vir die tamaties, terwyl die kleur van kool en wortels beter in die koue berging behou is. Chemiese veranderinge vir al drie groente was die sterkste teen omgewingstemperatuur, met beduidende (P < 0.05) verliese van askorbiensuur wat waargeneem is. Veranderinge is ook gemerk rakende totale pigmente, oplosbare vaste stowwe en suurgehalte. Daar was egter geen algemene beduidende neiging vir al drie groentes nie.
Beramings van koolstofvrystellings toon dat ná-oes-groenteverlies tot ongeoorloofde vrystelling van ten minste 1.37 tot 13.77 miljoen ton koolstofekwivalente (CO2eq.) op nasionale vlak bydra. Die verliese gaan ook gepaard met verbruik van ongeveer 3.74 tot 4.35 miljoen m3 vars water asook 14.79 tot 111.63 miljoen MJ fossielbrandstof. Die groente met die hoogste produksievolume en kleinhandelprys was die tamaties, en gevolglik het tamaties se ná-oes-verliese die ernstigste impak op die omgewing en op hulpbronne.
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Iqbal, Akhtar. "Effets de la nature et décomposition des mulchs de résidus végétaux sur les services assurés par les sols en agriculture de conservation : Étude expérimentale et modélisation." Thesis, Reims, 2013. http://www.theses.fr/2013REIMS001.
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En agriculture de conservation (AC), les résidus de cultures sous forme de paillis à la surface du sol associés à la suppression du travail du sol sont une composante intrinsèque des systèmes de culture. L'objectif principal de ce travail était de comprendre les effets de la nature et de la décomposition de mulch de résidus s sur les services d'approvisionnement et de régulation fournis par les sols dans les agrosystèmes en AC de régions tempérées (France) et tropicales (Madagascar et le Brésil). Des études expérimentales ont été réalisées pour obtenir des paramètres de décomposition pour une large gamme représentative de la qualité des résidus végétaux des agrosystèmes étudiés et pour tester et améliorer un modèle de décomposition des mulchs. Ensuite nous avons utilisé le modèle PASTIS_MULCH qui simule les biotransformations C et N et le transport de solutés dans les sols lors de la décomposition des mulchs.Pour la gamme de résidus de tiges testées, la rétention d'eau maximale a varié considérablement et ceci a été expliqué par les caractéristiques physiques du résidu. Avec les données obtenues par une série d'incubations de décomposition de résidus, nous avons proposé un ensemble de paramètres biologiques unique pour le module de décomposition CANTIS, simulant une large gamme de qualité des résidus de culture. L'étude expérimentale dans les colonnes de sol a montré que le mulch de maïs + dolique se décompose plus rapidement que mulch de blé + luzerne. Un régime de pluies fines et fréquentes augmente la décomposition du mulch par rapport à des pluies plus rares et plus fortes et cela est dû au maintien de l'humidité du mulch.Les simulations de scénarios avec PASTIS_MULCH ont montré que la pluie et les conditions d'évaporation classent les résidus de culture vis-à-vis de la décomposition lorsque ceux-ci sont placés en mulch à la surface des sols, tandis que les caractéristiques chimiques des résidus classent ceux-ci vis-à-vis de la décomposition lorsqu'ils sont incorporés. Aucune des situations étudiées pourrait être définie au vu des résultats de simulation comme étant adaptée à toutes les conditions pédo-climatiques et agricoles<br>In conservation agriculture (CA), crop residues mulches are associated to reduction or suppression of soil tillage and are an intrinsic component of CA. The objective of this work was to understand the effects of nature and decomposition of crop residue mulches on the provisioning and regulating services of agrosystems provided by soils under temperate (France) and tropical (Madagascar and Brazil) conditions. Experimental studies were realized to get decomposition parameters for a large range of residue quality representative of the agrosystems studied and to test and improve a MULCH model. Then we used PASTIS_MULCH model which simulates the C and N biotransformations and solutes transport in soils during mulch decomposition.For a range of plant-stem residues tested, the maximal water retention varied greatly and was only explained by the physical features of the residue. With a series of decomposition incubations, we proposed a single set of biological parameters for CANTIS decomposition module, simulating a large range of crop residue quality. Experimental study in soil columns showed that maize+dolichos mulch decomposed faster than wheat+alfalfa mulch. Frequent and light rain enhanced mulch decomposition compared to infrequent and heavy rain and this was due to the mulch remaining wetter with frequent rain.The simulations of scenarios with PASTIS showed that rain and evaporation conditions ranked crop residues decomposition when placed as mulches while the residue chemical characteristics ranked crop residues decomposition when incorporated. None of the situations studied would be defined as suitable in all pedo-climatic and agricultural conditions
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Milan, Abd Rahman. "Genetic manipulation of storage root development in horticultural crops." Thesis, De Montfort University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246516.
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Figer, Luiz. "Simulating a storage-production system with three oilseed crops." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/77462.
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Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology, Engineering Systems Division, 2012.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 53-54).<br>This work developed a simulation model that is intended to be used for strategic investment decisions by a company that operates in a wide range of activities in the agriculture business in Brazil. Mostly, it is a tool that allows the user, in this case the company management, to quantitatively assess the results of their qualitative expectations for the business environment. I found that the supply of grains is potentially a higher uncertainty factor than demand, that different configurations of crushing capacity and storage impact the results with significant difference, depending on the demand and supply scenarios even in the near future. Knowing that uncertainty is unavoidable and largely impacts the business, I measured it and found that, yield uncertainty alone can impact profits dramatically. The model developed in this paper can easily be leveraged to include more sophisticated crushing rules and up to date market data. It can also be run timely and produce tailored reports.<br>by Luiz Figer.<br>M.Eng.in Logistics
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Bowra, Steve. "Characterisation of storage lipid accumulation in developing fruits and cell cultures of coriander." Thesis, University of East Anglia, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302229.
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Awoh, Akué Sylvette. "Influence d'un plan d'eau de surface sur la vulnérabilité de l'eau pompée d'un puits en milieu rural /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 2006. http://theses.uqac.ca.
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Thèse (M.Sc.T.) -- Université du Québec à Chicoutimi, 2006.<br>La p. de t. porte en outre: Mémoire présenté à l'Université du Québec à Chicoutimi comme exigence partielle de la maîtrise en science[s] de la terre. CaQCU Bibliogr.: f. 120-125. Document électronique également accessible en format PDF. CaQCU
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Martinez-Kawas, Adrian. "A feasibility study of postharvest handling, storage and logistics of bioenergy crops." Diss., Kansas State University, 2013. http://hdl.handle.net/2097/16304.
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Doctor of Philosophy<br>Department of Grain Science & Industry<br>Dirk E. Maier<br>The feasibility of utilizing cellulosic biomass as an energy feedstock is dominated by factors such as facility location, feedstock availability, and transportation cost. The main goal of this research was to develop a GIS-based method that will generate more accurate biomass residue availability data as input data to biomass supply chain logistics models. This research was carried out in four objectives to ensure that, as improvement parameters were implemented, the methodology remained valid and became more accurate. The first objective compared an existing method to a proposed method to quantify feedstock availability given a facility’s location using a geographical information system. The proposed method proved to be more robust (by a factor of 1.45) than the existing method because it calculates the distance from the facility to farm fields using a real road network, and the acreage of crop-specific fields in a given service area based on crop season specific satellite images. The second objective implemented two improvement parameters to the previously proposed constant removal rate (CRR) method. It examined the effect of field-level yield variance and variable removal rates (VRR) on quantification of the feedstock availability supply for a biorefinery. The new VRR method predicted on average 113,384 ± 38,770 dry tons (DT) of additional residue per service area compared to the CRR method. The third objective further improved the VRR method by utilizing multiple crops as biomass sources and estimating VRR based on crop rotation. On average a 3,793 ± 5,733 DT per service area difference resulted when increasing the number of crop-specific VRR rates used to estimate feedstock quantification. The supplementary use of crop-specific VRR rates affected residue availability given a crop’s residue removal rate is influenced by crop yield, crop rotation, soil characteristics, as well as field location and management. The fourth objective assessed the suitability of potential feedstock storage locations (FSL) to store multi-crop biomass remotely based on a spatial and location-allocation analysis. The sensitivity analysis showed that scenario 2 (16-km; 10-mile service area) appeared to be the more cost-effective option given fewer FSLs (35) were needed and more demand points could be serviced (98.1%) compared to scenario 1 (8-km; 5-mile service area; 62.1% demand points; 50 FSLs), despite presumably higher transportation costs.
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Peddie, D. C. "Modelling and control of crop conditions in a bulk potato store." Thesis, University of Newcastle Upon Tyne, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372933.
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Prayogo, Cahyo. "Carbon storage and sequestration under different land uses with a focus on biomass crops." Thesis, University of Warwick, 2013. http://wrap.warwick.ac.uk/57556/.
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Climate change is caused by rising quantities of greenhouse gases, particularly CO2, in the atmosphere, largely through consumption of fossil fuels. There is interest in sustainable energy generation from renewable resources, particularly biomass crops to reduce reliance on fossil fuels. A key advantage of such energy systems is that they assimilate atmospheric CO2 and thus help mitigate climate change. Soil represents one of the largest pools of C in the biosphere and there is potential to use soil as a sink to sequester C to mitigate climate change. The aim of this project was to investigate soil C storage and sequestration in short rotation coppice (SRC), which is one of the major biomass cropping systems in temperate climates. 14 year old plantations of willow and poplar established at Rothamsted Research in Harpenden were used to investigate how the quantity and quality of organic matter under the SRC compare to that under adjacent land uses, including arable cropping, set-aside grassland and natural woodland. It was shown that change in land use to SRC led to increased C storage in soil relative to alternative agricultural systems, while conversion to setaside had no effect on soil C stocks. There was no difference in C storage under different poplar or willow cultivars. Differences in C storage between arable, SRC and set-aside plots reflected changes in C stocks at 0-30 cm depth with no change occurring to C at 30-60 cm. The quality of C was investigated by analysis of the light fraction organic matter pool which acts as an early indicator of long term changes in total soil organic matter. The work showed that the free LFOM pool responded to land use change while the physically protected intra-aggregate LFOM pool did not. While changes to amounts of LFOM following land use change occurred in soil at 0-30 cm depth, there were no changes at 30-60 cm depth. Fourier Transform Infra Red spectroscopy showed that the chemical composition of free and intra aggregate LFOM was different, and that composition of both pools was affected by land use. Fourier Transform Ion Cyclotron Resonance Mass spectroscopy was shown to provide fine level resolution of the composition of soluble organic matter, and demonstrated that the aromaticity and chain length of C was higher in woodland than arable soil. The potential to sequester C in soil as biochar is a promising option to promote longterm sequestration of C in soil. The potential to use a fluidised bed reactor to produce biochar was investigated. Life Cycle Analysis showed that 4700C was the optimal temperature to promote retention of C in biochar during pyrolysis, while minimising losses of C as bio-oil and gases. Addition of steam during pyrolysis was shown to increase the surface area of the resulting biochar. Addition of biochar to soil reduced net C mineralisation of soil organic matter and litter at a rate of 2 % w/w, but not at 0.5 % w/w. However both concentrations of biochar affected net mineralisation of N. Phospholipid fatty acid analysis showed that both concentrations of biochar altered microbial community structure, with fungal biomass in particular promoted by the addition of biochar. Overall the work demonstrates that SRC promotes significant storage of C within soil organic matter, which has implications for the overall energy budget of SRC biomass. Furthermore, conversion of biomass to biochar for land application provides opportunities for sequestration of C within soil. Application of biochar to soil would provide further benefits to the overall energy balance of SRC by reducing mineralisation rates of native soil organic matter and litter.
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Zan, Claudia. "Carbon storage in switchgrass (Panicum virgatum L.) and short-rotation willow (Salix alba x glatfelteri L.) plantations in southwestern Québec." Thesis, McGill University, 1998. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=20614.
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Carbon storage was compared between two perennial biomass energy systems, namely switchgrass (Panicum virgatum L.) and short-rotation willow Salix alba x glaffelteri L.) at 2 adjacent sites, and further compared with a corn cultivation, a 20-year-old abandoned field, and a mature hardwood forest, in southwestern Quebec. Aboveground carbon results indicated that switchgrass and corn had significantly greater carbon levels than willow at the less fertile site, but no significant differences were detected at the more fertile site. Root carbon results indicated that corn had significantly lower carbon levels than both perennial systems to a depth of 30 cm at both sites. However, switchgrass had significantly greater root carbon levels beyond 30 cm compared with willow and corn, and beyond 45 cm compared with the forest and abandoned field. These findings indicate that deep-rooted perennial grasses such as switchgrass have the potential to sequester carbon at deeper soil layers. Soil carbon results showed that at the more fertile site, willow was associated with significantly greater soil carbon levels than switchgrass. Moreover, both perennial crops had soil carbon levels that were greater than for corn, the abandoned field, and the forest. In contrast, at the less fertile site, no significant differences in soil carbon were detected between the various plant systems examined. The results of this study suggest that the perennial energy crops used, when grown on relatively fertile soils, have the potential to substantially increase soil carbon levels compared with conventional agricultural and/or forest systems. Consequently, when these crops are grown on less fertile soils, their added advantage of increasing carbon storage is lost.
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Neveur, Nancy. "Recherches sur la physiologie de la germination des graines et de la tuberisation des plantules de cyclamen persicum mill." Paris 6, 1987. http://www.theses.fr/1987PA066059.
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Examen de l'action de la temperature, de la lummiere et de traitements par la gibberelline sur la germination des graines de cyclamen. Developpement de la plantule et formation du tubercule au niveau de l'hypocotyle. Etude biochimique de l'utilisation des reserves et de la synthese d'amidon et de glucofructosanes dans le tubercule
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Shikwambana, Kingsly. "Effect of harvest time, post-harvest storage and ripening temperature on fruit quality of reed avocado cultivar." Thesis, University of Limpopo, 2016. http://hdl.handle.net/10386/2049.
Full textAbstract:
Thesis (M. Sc. (Agriculture, Horticulture)) --University of Limpopo, 2016<br>‘Reed’ avocado is a late season cultivar introduced to South Africa from California. The cultivar has shown good adaptation and produces quality fruit with export potential. Its pre-harvest adaptation and production aspects have been researched and documented. However, the effect of harvest time, post-harvest storage and ripening temperature has not been comprehensively studied on this newly introduced ‘Reed’ avocado cultivar. Therefore, the aim of this work was to investigate the effect of different harvest time, post-harvest storage and ripening temperature on the quality of late season ‘Reed’ avocado fruit. Matured ‘Reed’ avocado fruit were harvested based on moisture content indexing in December (2015) and January (2016). The experiment was carried out in a factorial, arranged in a completely randomised design (CRD) with three replicates. Treatment factors were: 2 x harvest time (mid-and late), 2 x post-harvest storage (2.0 and 5.5°C), 3 x ripening temperature (16, 21 and 25°C) and 5 x ripening day (0, 2, 4, 6 and 8). Fruit were stored at 2.0 and 5.5°C for 28 days, thereafter, ripened at 16, 21 and 25°C until fully ripe. During ripening, fruit were evaluated for weight loss, skin colour, firmness, respiration rate, physiological and pathological disorders. Mid-harvest fruit had higher moisture content when compared with late harvest fruit. However, harvest time, post-harvest storage, ripening temperature and ripening time (days) significantly influenced fruit weight loss, firmness, respiration rate, ripening percentage of ‘Reed’ avocado fruit during ripening. Moreover, fruit firmness decreased faster at higher temperatures (25 and 21°C) with fruit ripening within 4 and 6 days, respectively. In addition, ripening at a lower temperature (16°C) was slower with fruit fully ripened within 8 days after withdrawal from cold storage at both harvest times. ‘Reed’ avocado fruit respiration rate followed a climacteric pattern, however, significantly higher rate at higher temperature (25°C) when compared with lower temperature (16°C) after withdrawal from cold storage during both harvest times. Interestingly, mid-harvest fruit showed high electrolyte damage after withdrawal from 2.0°C when compared with late harvest fruit at the same temperature. Furthermore, mid-harvest fruit stored at 2.0ºC and ripened at 21°C showed higher chilling injury when compared with fruit ripened at 16 and 25°C. High electrolyte leakage positively correlated (R2 = 0.242) with high chilling damage for
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mid-harvest fruit stored 5.5°C. Treatment factors had a significant effect (P < 0.05) on lightness (L *) and hue angle (h
) but no significant effect (P > 0.05) on chroma (C *) and eye colour of ‘Reed’ avocado fruit during ripening, irrespective of harvest time. Overall results showed a visual change in ‘Reed’ avocado skin colour, with eye colour changing from green to bright yellow. Furthermore, late harvest fruit showed high post-harvest pathological diseases after removal from high temperature (5.5°C) when compared with mid-harvest fruit stored at low storage temperature (2.0°C). Ripening at a higher temperature (21 and 25°C) resulted in higher incidence of stem-end rot and body rot when compared with lower temperature (16°C) for both harvest times. Late harvest fruit showed a higher incidence of vascular browning at higher ripening temperatures (21 and 25°C) when compared with lower temperature (16°C) after withdrawal from cold storage. Moreover, overall results showed that harvest time, post-harvest storage and the ripening temperature had a profound influence on the quality of ‘Reed’ avocado fruit. In conclusion, ‘Reed’ avocado fruit can be harvested during mid- or late season and stored at recommended low temperature (2.0ºC); and thereafter, ripened at either 16 or 21ºC. In addition, future studies should focus on identifying pre-harvest practices that promote higher post-harvest fruit quality for ‘Reed’ avocado fruit under South African production environment.
Keywords: ‘Reed’ avocado fruit; firmness; electrolyte leakage; respiration rate; stem-end rot; body rot; vascular browning
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Sundberg, Markus. "I skuggan av stormaktens sista krig : Inre förhållanden i den svenska militärstatens Jämtland under stora nordiska kriget." Thesis, Mittuniversitetet, Institutionen för humaniora och samhällsvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-36318.
Full textAbstract:
This paper is focused on the consequences of the drawn-out conflict, known as ”the great northern war”, which lasted from the start of the 18th century up to 1721. More precisely the focus is at the economic situation facing the agrarian lower classes during these years, as well the nature in which their discontent presented itself. The study is restricted to one particular region of early-modern Sweden, Jämtland. The subjects that are examined are: - The amount of tax that were not paid or delivered to the proper authorities in time. - Contemporary depictions of the situation for the agrarian lower classes in Jämtland. - Taxes from earlier years yet to be paid.- Abandoned farms during the period. - Crop failures and their connection to the economic situation. - The so called ”everyday forms of resistance” in Jämtland as an expression of the people’s discontent towards the ruling figures in Stockholm – manifested against their local representatives.<br><p>Betygsdatum 2019-06-13</p>
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Lindner, Steve [Verfasser], and Dennis [Akademischer Betreuer] Otieno. "Determining the Role of Agro-Ecosystems in a Changing Climate : Quantification of CO2 exchange, Carbon allocation and Storage in the Main Agricultural Crops of South Korea / Steve Lindner. Betreuer: Dennis Otieno." Bayreuth : Universität Bayreuth, 2016. http://d-nb.info/1108406114/34.
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Ben, Salem Moncef. "Etude comparative de la resistance a la secheresse de quelques varietes de ble." Paris 7, 1988. http://www.theses.fr/1988PA077012.
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On montre que la resistance du ble a la contrainte hydrique est associee au maintien d'un nombre d'epis fertiles et d'un nombre de grains par epi eleves, a une petite taille du grain et a une capacite de recuperation elevee. On a evalue les besoins globaus optima en eau a 440 mm et on a montre qu'une mauvaise efficacite de l'utilisation de l'eau peut etre la consequence d'un developpement foliaire surdimensionne. Une production en grains stable en cas de carence hydrique est liee a une photosynthese globale elevee, a de grandes capacites d'accumulation et de mobilisation der reserves glucidiques. Les mecanismes de resistance differant d'une variete a l'autre, on tente de definir un ideotype de ble adapte aux zones arides
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Müller, Cecilia. "Wrapped forages for horses /." Uppsala : Dept. of Animal Nutrition and Management, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/200744.pdf.
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Mngqawa, Pamella. "Preliminary investigation of the natural contamination of agricultural crops with selected mycotoxins in northern rural South Africa (Limpopo and Mpumalanga Provinces)." Thesis, University of Western Cape, 2013. http://hdl.handle.net/11394/3456.
Full textAbstract:
>Magister Scientiae - MSc<br>Subsistence farmers may contribute significantly to food production, food
security, and employment in South Africa. However poor storage practices and
contamination with mycotoxins, particularly fumonisins and aflatoxins impacts
adversely on production, food safety and food security. Mycotoxins are toxic
natural food-borne compounds which frequently contaminate agricultural produce
worldwide. They are hazardous to humans and animals and result in significant
production losses for farmers. This study focused on former Bantustans in Northern South Africa, namely Vhembe District Municipality (Limpopo) and Gert Sibande District Municipality (Mpumalanga). The aim was to assess mycological and mycotoxin contamination of crops grown by subsistence farmers. A semi-structured questionnaire was administered to randomly thirty-nine households. Data on demographics, storage
practices and production during period of 2011 and 2012 cropping seasons were
collected. One hundred and fifteen (115) crop samples (maize, beans and peanuts)
were collected for analysis. Standard mycological methods and validated mycotoxin analysis methods (HPLC and LC- MS/MS) were used. It was found that maize was the staple food in both provinces, with a significant difference (p = 0.0184) in its production between the two districts; Vhembe produced 0.6 tonnes compared to 2.4 tonnes in Gert Sibande. The majority of the farmers for storage used traditional open wooden cribs (15/20) and steel tanks (5/20) while VDM farmers used sealed store houses 5/19 and 15/19 used polystyrene sacks. Aflatoxin occurrence was low with <1% of GSDM samples
contaminated compared to 11% of VDM samples. No significant difference (p >
0.05) was observed in the aflatoxin contamination in VDM samples between the
year 2011 and 2012. Samples from VDM households had higher Aspergillus
fungal infection (maximum incidence 69%) compared to GSDM (27%) over both
seasons. The most frequently isolated Fusarium species in VDM samples was F.
verticillioides (92%; 93%), and F. subglutinans (97%; 80%) in GSDM samples over seasons 2011 and 2012, respectively. Highest levels of fumonisins (FB1+ FB2) ranged between 1010 μg/kg and 12168 μg/kg with less than 30% extremely contaminated above the regulated limit in 91% of samples from Limpopo over both seasons (2011 and 2012). Fumonisin levels between the two seasons in VDM showed no significant difference (p>0.05). Only three (less than 5%) from 68% GSDM contaminated maize samples were above the FB1 and FB2 limit. In 2011, there were two highly contaminated maize samples (1762 μg/kg and 4598 μg/kg) with the other samples less than 600 μg/kg, whereas in season two (2012) all samples were below 200 μg/kg, except one highly contaminated sample (26115 μg/kg). None of the beans and peanuts
from Mpumalanga was contaminated with mycotoxins above the recommended limit, but from Limpopo 1/5 peanuts was found contaminated with aflatoxin G1 (41 μg/kg).
Natural occurrence and contamination of both fumonisin and aflatoxin in stored
home-grown maize from VDM was significantly (p < 0.0001) higher than GSDM
over both seasons. In general, Limpopo farmers’ experience lower harvests and
greater mycotoxin contamination of agricultural produce. This may be attributed
in part to poor storage practices and environmental and climatic conditions in that
agro-ecological zone.
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Ricks, Christian B. "The Prolamins of Pearl Millet." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd1969.pdf.
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Ourry, Alain. "Contribution a l'etude du metabolisme de l'azote chez le ray-grass anglais en depart de croissance apres une coupe." Caen, 1988. http://www.theses.fr/1988CAEN2016.
Full textAbstract:
Trois axes de recherches ont ete etudies: mobilisation - renouvellement des reserves azotees (turn-over de l'azote organique des racines et des chaumes, proteolyse), nutrition azotee et role osmotique du nitrate
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(6668768), Smith G. Nkhata. "POST HARVEST STORAGE OF BIOFORTIFIED MAIZE IN PURDUE IMPROVED CROP STORAGE (PICS) BAGS AND EFFECT ON SUBSEQUENT FLOUR RHEOLOGY AND CAROTENOID BIOACCESSIBILITY." Thesis, 2019.
Find full textAbstract:
<p>Successful adoption of biofortified orange maize in developing countries requires careful consideration of factors across the chain from farm to fork. This includes consideration of post-harvest storage conditions optimal for the retention of both proviatamin A carotenoids and cooking quality critical to consumers. In these considerations, identification of economical storage methods is critical considering the limitations within specific countries that biofortified maize is being disseminated. To address these points, this dissertation research focused on evaluation of the utility of the Purdue Improved Crop Storage (PICS) bags as a post-harvest storage solution for biofortified maize. The specific focus of this research was to monitor retention of provitamin A and other carotenoids in two biofortified maize genotypes (OPVI and OPVII) as well as storage effect on flour functionality. Finally, a preliminary assessment of the impacts of storage on carotenoid bioaccessibility was completed to begin to translate findings to practice.</p><p>Maize grain from 2016 harvest was stored at ambient conditions for eight months in either PICS bags with or without an O<sub>2</sub> scavenger, (PICS-oxy) and (PICS-noxy), respectively and compared to storage in common polypropylene woven bags (control). After 4 months of storage carotenoid content was significantly higher (p<0.05) in PICS-oxy compared to PICS-noxy and woven bags demonstrating the importance of entrapped oxygen on maize carotenoid degradation. Furthermore, differences in carotenoid stability between maize genotypes were observed with OPVI having higher retention than OPVII. After 8 months, carotenoid retention remained dependent on storage bag and genotype with retention being greater in PICS-oxy and PICS-noxy compared to woven bags. However, final levels after 8 months were more similar between storage methods. Overall, oxygen content and genotype were found to be determining factors in the effectiveness of PICS to mitigate carotenoid degradation during post-harvest storage of maize.</p><p>While reducing the rate of carotenoid degradation during postharvest storage of biofortified maize is important, success of biofortified maize is also dependent on consumer adoption of these grains and their performance in traditional food preparation. Assessment of the rheological and functional properties of these two biofortified maize genotypes as a function of post-harvest storage was completed to assess the impact of post-harvest storage in PICS bags on flour functionality and rheological properties for the two biofortified orange maize genotypes and a control white maize genotype. Flour pasting profiles were assessed initially and at 4 and 8 months. After 8 month storage in woven and PICS bag, OPVI and OPVII produced porridges with similar viscosities to their initial viscosities regardless of postharvest storage type. White maize viscosities progressively decreased with storage and were significantly lower (p<0.05) in woven compared to PICS storage. Sequestration of oxygen (PICS-oxy) had modest but significant effects (p<0.05) on key pasting parameters including peak and final viscosities. These results suggest that oxygen sequestration has a critical effect on final flour functionality. DTT treatment partially restored flour pasting profiles suggesting disulfide linkages may modify pasting profiles of flour. There was also an increase in free ferrulic and <i>p</i>-coumaric acids during storage which may have contributed to observed decreases in porridge viscosities. Evidence of this was found through Raman spectroscopy with spectral intensity at both 478cm<sup>-1</sup> and 2911cm<sup>-1</sup> decreasing with storage suggesting the potential for structural changes induced by storage on starch polymer. While storage in PICS bags does not seem to adversely affect flour functionality it may provide some additional economic benefit resulting from requiring proportionally less flour to achieve similar final viscosities as flour from woven bag stored grains. </p><p>Finally, the effect of postharvest storage on bioaccessibility of carotenoids was explored using experimental wet cooked porridges made from ‘fresh’ and stored grains using an established three stage in-<i>vitro</i> digestion model. Relative carotenoid bioaccessibility (% micellarization) was generally higher in less viscous porridge made from grains stored in woven bags compared to porridge from initial or PICS bags stored grains suggesting that higher viscosity might partly explain lower relative bioaccessibility in porridge from grains stored in PICS bags. Absolute carotenoid bioaccessibility from experimental porridge was dependent on carotenoid species and storage system. Extrapolation of relative bioaccessibility (%) to absolute bioaccessibility (µg/g flour) suggests that fresh grains and their corresponding porridges would provide more absolute bioaccessible carotenoids compared to stored grains despite some improvement in relative accessibility. As such, storage losses remain the main factor impacting total available carotenoids and should continue to be an area of focus for future mitigation. With the potential to minimize post-harvest losses, improve carotenoid retention and provide a product with improved cooking performance, PICS bags do appear to offer a viable storage alternative to improve both food and nutrition security in developing countries.</p><p></p>
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Tsai, Ching-Ying, and 蔡晴瀅. "Effects of Crop Season, Harvesting Time and Storage Time on the Quality of Sweet Potato (Ipomoea batatas (L.) Lam.) var Simon No.1." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/77682925865602057764.
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(10752345), Pragya Kandel. "ASSESSMENT OF POSTHARVEST PEST MANAGEMENT PRACTICES IN NEPAL AND EFFICACY OF HYPOXIA FOR CONTROLLING SITOPHILUS ORYZAE L. (COLEOPTERA: CURCULIONIDAE)." Thesis, 2021.
Find full textAbstract:
Farmers in Nepal lose about a third of their harvested grain due to postharvest handling and storage. This has led to food insecurity and economic losses. Despite the importance of postharvest, the grain storage system in Nepal relies on traditional storage structures like bamboo granaries. The incidence of storage pests is reported up to 100% in these structures. To minimize the storage loss, farmers use different grain protection methods including toxic chemicals. Multiple cases of pesticides-related poisoning and deaths have been caused by misuse and overuse of pesticides. To push safer, chemical-free alternatives like hermetic storage it is important to understand current pest challenges and management practices in Nepal. Adaptation of chemical-free pest management strategies like hermetic storage largely depends upon basic and applied laboratory research findings. Determining the baseline adult mortality under various hypoxia levels and subsequent insect emergence will help determine the effectiveness of a low oxygen environment in controlling <i>Sitophilus oryzae</i> (L.). This would increase our understanding of hermetic storage technology and help improve its application to both farmers and commercial users and serve as a possible substitute to traditional or chemical pest control methods. In chapter one, I report the result of the survey conducted in Nepal to understand i) current post-harvest storage practices and (ii) assessment of the best delivery approach for storage innovations. In chapter 2, I report the result from laboratory experiment conducted to understand the lethality of hypoxia at 5% oxygen level and below against <i>Sitophilus oryzae</i> (L.), which is a major storage pest reported by farmers in Nepal.
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Nketia, Kwabena Abrefa. "Space-time modelling of seasonal soil moisture for improved crop production – the case of the Guinea savannah region, Ghana." Thesis, 2020. http://hdl.handle.net/21.11130/00-1735-0000-0005-1527-8.
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Siboza, Xolani Irvin. "Methyl jasmonate and salicylic acid enhance chilling tolerance in lemon (citrus limon) fruit." Thesis, 2013. http://hdl.handle.net/10413/10872.
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South African ‘Eureka’ lemon fruit must be exposed to chilling temperatures (± 0.6°C) as a mandatory quarantine treatment against insect pests for all its overseas markets. Chilling lemon fruit at such temperatures may develop chilling injury (CI) symptoms on the flavedo. This negative effect on fruit quality reduces fruit marketability. This study evaluated postharvest factors influencing physiological, biochemical and ultra-structural mechanisms involved in alleviating CI in lemon fruit. It was hypothesised that treatment with methyl jasmonate (MJ) and salicylic acid (SA) may enhance chilling tolerance in lemon fruit by maintaining cellular integrity and inducing synthesis of enzymatic and non-enzymatic antioxidants. Furthermore, fruit susceptibility to CI was associated with the source of fruit. Lemon fruit were harvested from three locations representative of moderate subtropical, warm temperate and cool subtropical environments. Harvested fruit were treated either with 10 μM MJ, 2 mM SA or 10 μM MJ plus 2 mM SA, stored either at -0.5, 2 or 4.5°C for 0, 7, 14, 21, or 28 days and afterwards transferred to 23°C for a week as shelf-life simulation. Thereafter, fruit were evaluated for alterations in physiological, biochemical and ultra-structural features involved in the manifestation of CI symptoms.
Chilling damage was more severe in untreated lemon fruit than in treated lemon fruit. Storing lemon fruit at 4.5°C accelerated the manifestation of CI symptoms more so than at 2°C while storage at -0.5°C delayed the manifestation of CI symptoms. Lemon fruit of moderate subtropical origin were more chilling-tolerant than lemon fruit of warm temperate and cool subtropical origin. Treatment with 10 μM MJ plus 2 mM SA significantly (P < 0.05) improved chilling tolerance in lemon fruit. This treatment effectively maintained membrane integrity, thereby retarding electrolyte leakage and membrane lipid peroxidation as well as mass loss and respiration rate. Treatment with 10 μM MJ plus 2 mM SA was also effective in enhancing the antioxidant concentrations of
vitamin E and carotenoids. The production of these antioxidants could have been part of a defence system against chilling damage, reducing CI and maintaining fruit quality.
Treatment with 10 μM MJ plus 2 mM SA enhanced the concentration of compounds involved in chilling resistance, such as proline, soluble sugars, ascorbic acid and total phenolics as well as the enzyme phenylalanine ammonia-lyase (PAL). The enhancement of the defence mechanisms may have played a role in enhancing chilling tolerance in lemon fruit. The treatment also inhibited certain enzymes involved in tissue browning, such as peroxidase (POD) which might have contributed to delaying manifestation of symptoms. Polyphenol oxidase (PPO) was found to not be a good biochemical marker of the occurrence of CI. Treatment with 10 μM MJ plus 2 mM SA appeared to be able to enhance chilling tolerance in lemon fruit by maintaining the ultra-structure of the cuticle, cell wall integrity, cell membrane of parenchyma cells of the flavedo. This treatment also preserved the mineral nutrients of the flavedo (carbon, oxygen, phosphorus, potassium, calcium, magnesium, sulphur, sodium, silicon and aluminium) during cold storage. This could have played a role in protecting the fruit against chilling stress and maintaining fruit quality.
Treatment with 10 μM MJ plus 2 mM SA reduced ROS production, while the activity of enzymatic antioxidants such as catalyse (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR), and accumulation of essential proteins was enhanced. This increase in activity of enzymatic antioxidants and the presence of stress-responsive proteins in the lemon flavedo could have been directly involved in enhancing chilling tolerance. The CI symptoms were accompanied by an increase in membrane permeability, membrane lipid peroxidation as well as phospholipase D (PLD) and lipoxygenase (LOX) activity; however, treatment with 10 μM MJ plus 2 mM SA effectively reduced the membrane permeability, membrane lipid peroxidation, and PLD and LOX activity induced by the cold treatment. This could have contributed to the efficacy of 10 μM MJ plus 2 mM SA in inhibiting the manifestation of CI symptoms.
Treatment with 10 μM MJ plus 2 mM SA enhanced flavedo total antioxidant capacity measured by ferric reducing ability of plasma; 2,2-diphenyl-1-picrylhydrazyl; 2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) and the oxygen radical absorption capacity assays. The enhancement of antioxidant capacity in lemon flavedo could have contributed to the fruit’s chilling tolerance. Therefore, the effect of 10 μM MJ plus 2 mM SA treatment, enhancing chilling tolerance, may be attributed to its ability to enhance enzymatic and non-enzymatic antioxidants; activate essential proteins and mitigate the effect of ROS accumulation. With the use of 10 μM MJ plus 2 mM SA treatments, the South African citrus industry will be able to meet the quarantine temperature requirements for exportation of lemon fruit whilst reducing economic losses, depending on the preharvest conditions experienced by the fruit in each shipment.<br>Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2013.
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(8071469), Benjamin D. Reinhart. "Evaluating drainage water recycling in tile-drained systems." Thesis, 2019.
Find full textAbstract:
<p>Drainage water recycling (DWR) is the practice of capturing,
storing, and reusing subsurface drained agricultural water to support
supplemental irrigation and has recently been proposed as a practice for
improving the crop production and water quality performance in the tile-drained
landscape of the U.S. Midwest. This study describes the development of a
modeling framework to quantify the potential irrigation and water quality
benefits of DWR systems in tile-drained landscapes and the application of the model
using ten years of measured weather, tile drain flow and nutrient
concentrations, water table, and soil data from two sites in the U.S. Midwest.
From this modeling framework, the development and testing of an open-source
online tool is also presented.</p><p></p><p>A spreadsheet model was developed to track water flows
between a reservoir and drained and irrigated field area at each site. The
amount of tile drain flow and associated nutrient loads that could be captured
from the field and stored in the reservoir was estimated to calculate the
potential water quality benefits of the system. Irrigation benefits were
quantified based on the amount of applied irrigation annually. A reservoir size
representing 6% to 8% of the field area with an average depth of 3.05 m was sufficient
in meeting the annual irrigation requirements during the 10-year period at each
site. At this reservoir size, average annual nitrate-N loads were reduced by
20% to 40% and soluble reactive phosphorus loads by 17% to 41%. Variability in
precipitation within and across years, and differences in soil water
characteristics, resulted in a wide range of potential benefits at the two
sites.</p><p>An online tool was developed from the model, and a
variance-based global sensitivity analysis was conducted to determine
influential and low-sensitivity input parameters. The input parameter, depth of
root zone, was the most influential input parameter suggesting that the
estimation of total available water for the field water balance is a critical
component of the model. Input settings describing the irrigation management and
crop coefficients for the initial establishment and mid-season crop growth
periods were also influential in impacting the field water balance. Reservoir
seepage rate was influential in regard to the reservoir water balance,
particularly at larger reservoir sizes. Sensitivity analysis results were used
to develop a user-interface for the tool, Evaluating Drainage Water Recycling
Decisions (EDWRD).</p><p>This study shows that DWR is capable of providing both irrigation and water quality benefits in the tile-drained landscape of the U.S. Midwest. The developed modeling framework supports future research on the development of strategies to implement and manage DWR systems, and the online tool serves as a resource for users to increase their awareness and understanding of the potential benefits of this novel practice.</p><p></p>
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Daniels, Lisa. "The economics of staggered production and storage for selected horticultural crops in the Gambia." 1988. http://catalog.hathitrust.org/api/volumes/oclc/19617805.html.
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Thesis (M.S.)--University of Wisconsin--Madison, 1988.<br>Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 112-116).
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Damick, Alison. "Complex Ecologies: Micro-Evidence for Storage Landscapes in Early Bronze Age Lebanon." Thesis, 2019. https://doi.org/10.7916/d8-4rf7-hw75.
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This dissertation presents the results of an archaeological investigation into the environmental strategies of emergent aggregated societies in coastal Lebanon over the course of the Early Bronze Age (c. 3200-2400 BCE). The Early Bronze Age marked not only the rise of large-scale urbanized polities in neighboring regions of Mesopotamia and, to a lesser extent, the Southern Levant, but it took place during the dramatic climate variability of the Middle Holocene. This dissertation uses the analysis of microbotanical and ground stone tool data to assess agricultural strategies, land use, and plant processing technologies at two settlements along the Lebanese littoral during this time of political and climatic upheaval. By comparing phytolith data, stone tool use-wear and microbotanical residues from grinding tools from the sites of Sidon and Tell Fadous-Kfarabida, this project reconstructs local plant and stone environments and the choices that populations were making about those resources over time. It concludes that selectivity between conservative and innovative plant management technologies allowed these settlements to maintain small-scale local networks built into the landscape and to participate with, while resisting incorporation into, growing urban and state economies nearby.
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Vilakazi, Busisiwe. "The effect of water stress and storage conditions on seed quality of chickpea genotypes characterized by differences in seed size and coat colour." Diss., 2018. http://hdl.handle.net/11602/1086.
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MSCAGR (Plant Production)<br>Department of Plant Production<br>Chickpea (Cicer arietinum L.) is an excellent utilizer of residual soil moisture in agricultural ecosystems. However, its seed quality and hence reproduction is constrained by water stress, seed size and storage conditions. This study was carried out at the University of KwaZulu- Natal (UKZN), Pietermaritzburg Campus. It was conducted to evaluate the performance of chickpea genotypes (Desi-K, Saina-K and ICCV-K) with different seed sizes on seedling emergence (i), seed ageing effect on seed quality and imbibition of genotypes produced under water stressed and non-stressed conditions (ii), and (iii) the effect of water stress during seed development on sugars and protein accumulation, germination and seed vigour. Pot experiments were conducted under glasshouse / tunnel conditions at the Controlled Environment Facilities (CEF). The experiment for objective 1 was laid out as a single factor in completely randomized design (CRD). Data on emergence rate, final hypocotyl and complete emergence was collected. The small seeded Desi-K showed higher and faster emergence compared to medium sized Saina-K and large seeded ICCV-K. In the experiment of the second objective, seeds of the three genotypes were first obtained by production under water stressed and non-stressed growing conditions. They were then aged for 0, 1, 3, 5, or 7 days at 41 ºC and 100% relative humidity to form a 2 x 3 x 5 (water levels x genotypes x ageing) factorial design. Data was collected on germination percentage (GP), mean germination time (MGT), electrical conductivity (EC), tetrazolium chloride test (TZ) and imbibition weight. Seed ageing caused progressive loss of seed viability and vigour in all genotypes, which resulted in lower GP, delayed MGT, reduced TZ staining, cell death and high solute leakage from the seeds produced under the two water regimes. However, the effect was more severe under water stressed conditions. In the experiment for objective 3, seeds of all three genotypes were larger when grown under non-stressed condition compared to those under water stressed condition. These larger seeds had higher seed viability and germination percentage but lower electrical conductivity and mean germination time. Stressed seeds had higher soluble sugars than non-stressed seeds. It was deduced that irrigation during seed development reduces the final sugars and protein content but increases the seed size and physiological quality parameters allied to production of chickpea. Therefore, water provision to chickpea crop is critical during seed development.<br>NRF
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Agboka, Komi. "Developing and testing plant health management options against the maize cob borer Mussidia nigrivenella Ragonot (Lepidoptera: Pyralidae) in West Africa." Doctoral thesis, 2009. http://hdl.handle.net/11858/00-1735-0000-000D-F24C-4.
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