Tesi sul tema "Seed yield and quality"
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1
Kittock, David L., Wallace C. Hofmann, B. Brooks Taylor, Peter T. Else, Joel Malcuit e Carl Michaud. "Emergence and Yield from High and Low Quality Upland Cotton Seed". College of Agriculture, University of Arizona (Tucson, AZ), 1985. http://hdl.handle.net/10150/204030.
2
Kittock, D. L., W. C. Hofmann, J. Malcuit, P. Else e C. Michaud. "Emergence and Yield from High and Low Quality Upland Cotton Seed". College of Agriculture, University of Arizona (Tucson, AZ), 1986. http://hdl.handle.net/10150/219704.
Abstract (sommario):
The 1985 and 1986 Cotton Reports have the same publication and P-Series numbers.Low quality Deltapine (DP) 41 seed had lower germination, lower cold test germination, reduced stand, and reduced lint yield in four tests in Arizona in 1985.
3
Rethwisch, Michael D., e Steven McGuire. "Effects of Dry Seed+ Applied at Planting on Alfalfa Yield and Quality". College of Agriculture, University of Arizona (Tucson, AZ), 1997. http://hdl.handle.net/10150/202448.
Abstract (sommario):
This experiment tested the effects of a cytokinin containing product (Dry Seed +) on CUF 101 alfalfa when applied with the seed at planting on October 24, 1996, at the rate of 1 /lb product to 100 lb of alfalfa seed. Data indicated a non - statistical yield response averaging 200 lbs an acrefrom treated fields the first cutting, valued at $11 /acre, but yields were identical the second harvest. Alfalfa quality means were very similar for both harvests. A positive net return of $9.76 /acre was noted by using Dry Seed +. More testing is suggested to confirm these findings.
4
Hadavizadeh, Alireza. "The effect of mother plant nutrition on seed yield, quality and vigour in peas (Pisum sativum)". Thesis, University of Bath, 1986. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233622.
5
Husman, S. H., W. B. McCloskey, T. Teegerstrom, P. Clay, R. Norton e K. White. "Yield, Quality, and Economic Comparison of Single and Double Seed Line Per Bed Cotton Production". College of Agriculture, University of Arizona (Tucson, AZ), 2002. http://hdl.handle.net/10150/197719.
Abstract (sommario):
Three experiments were conducted in Maricopa, Marana, and Glendale, Arizona in 2001 to measure cotton growth, yield, micronaire, and production costs in single and double seed line per bed systems on 32 and 40 inch beds. Canopy development was faster and canopy closure was greater in the double seed line than in the single seed line systems and was greater in the 32 inch than in the 40 inch row systems. At Maricopa, the single line 32 inch system yield of 1571 lbs./A was significantly greater than the yields of the other seed line/row spacing systems. The yields of the single line 40 and the double line 32 inch systems were not significantly different at 1476 and 1411 lbs. of lint/A, respectively, and the yields of the double line 32 and the double line 40 inch systems also were not significantly different at 1411 and 1396 lbs. of lint/A, respectively. There were no significant lint yield differences at the Marana or Glendale location. At Marana, the lint yields were 1063 and 1066 lbs./A for the single and double seed line 40 inch row spacing systems, respectively. At Glendale, the single and double seed line 38 inch row spacing systems yielded 1474 and 1551 lbs. of lint/A, respectively. In all 2001 experiments, there was a trend for reduced micronaire in the double seed line per bed systems compared to the single seed line per bed systems. At Maricopa, the average micronaire was 5.0 and 4.7 for the single and double seed line per bed 32 inch row system, respectively, and 5.2 and 4.9 for the single and double seed line per bed 40 inch row systems, respectively. At Marana, the micronaire was 4.7 and 4.5 for the single and double seed line per bed 40 inch row systems, respectively. At Glendale, the micronaire was 5.1 and 4.6 for the single and double seed line per bed 38 inch row systems, respectively. Production costs were similar for the single and double seed line per bed systems. Additional research will be conducted in 2002 to determine the optimum plant populations and in-row plant spacings for double seed line per bed production systems.
6
Ghassemi-Golezani, Kazem. "The effects of seed quality on cereal yields". Thesis, University of Reading, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306481.
7
Hofmann, Wallace C., e David L. Kittock. "The Effect of Low Quality Seed on Lint Yields". College of Agriculture, University of Arizona (Tucson, AZ), 1986. http://hdl.handle.net/10150/219730.
Abstract (sommario):
The 1985 and 1986 Cotton Reports have the same publication and P-Series numbers.Comparison of 23 low quality upland cotton seed lots with high quality lots in 19 tests over 4 years showed consistent lint yield reduction from low quality seed. The low quality seed lots produced an average of 226 pounds less lint/acre than high quality seed. At $0.60/pound of lint that is $135.37/acre. By analysis of covariance, which adjusted lint yield for equal stand, poor stand explained 162 pounds of lint loss ($97.20/acre) and apparent reduced seedling vigor accounted for 64 pounds of lint loss or $38.16/acre.
8
Bianchetti, Grégoire. "Impacts de stress biotique et abiotique sur l’acquisition de la qualité nutritionnelle et physiologique de la graine de colza (Brassica napus L.)". Thesis, Rennes, Agrocampus Ouest, 2021. http://www.theses.fr/2021NSARB250.
Abstract (sommario):
L’acquisition de la qualité de la graine est un processus contrôlé par l’expression de nombreux acteurs moléculaires et métaboliques interconnectés et modulés par l’environnement. Les modélisations climatiques actuelles prévoient l’augmentation des contraintes environnementales multiples et combinées sur les cultures, dont les effets complexes s’avèrent généralement peu prédictibles. Une meilleure compréhension de ces impacts sur le développement des graines représente un levier pertinent pour l’augmentation de la résilience environnementale des productions agricoles. Le travail de thèse s’est inscrit dans cette thématique scientifique et a cherché à répondre à la question suivante : quels sont les impacts d’une combinaison de stress biotique et abiotique sur l’élaboration du rendement et l’acquisition de la qualité de la graine de colza ?Pour y répondre, deux génotypes de colza ont été cultivés au sein d’un large dispositif expérimental et exposés à une combinaison de stress majeurs pour cette culture que sont le déficit hydrique et la hernie des crucifères, causée par le pathogène Plasmodiophora brassicae. Des impacts du déficit hydrique sur les plantes et la qualité des graines matures ont été identifiés. Par la suite, des données RNAseq, métaboliques et physiologiques ont permis de caractériser le programme transcriptionnel développemental des graines de colza et d’identifier des modulations spécifiques d’un stress ou de leur combinaison sur la transcription des gènes et l’acquisition de la qualité de graine en développement. Les corrélations entre ces modulations et leurs perspectives agronomiques sont discutéesSeed quality acquisition is an environmental moduled process that is finely controlled by the expression of many interconnected molecular and metabolic actors. Current climate projections predict that crops will be exposed to an increase of multiple and combined environmental constraints, leading to complex and generally non-deductible impacts. A better knowledge of these impacts on seed development, still poorly studied, appears thus as a relevant lever to enhance environmental resilience of agricultural productions. This thesis work is part of this scientific theme and sought to answer the following question: what are the impacts of a combination of biotic and abiotic stress on the yield elaboration and seed quality acquisition of the rapeseed?To answer this question, two rapeseed genotypes were grown in a large experimental device and subjected to a combination of stresses that are major for this crop, the water deficit and clubroot, caused by the pathogen Plasmodiophora brassicae. Signature impacts of water deficit on plants and mature seed quality have been identified using physiological and metabolic data, as well as germination kinetics. Subsequently, RNAseq, metabolic and physiological data, were used for the characterization of the rapeseed transcritional developing seed gene transcrotions and quality acquisition. The correlations between these modulations and their agronomic perspectives are discussed
9
Bilbe, Sara Ann. "The relationship between soybean (Glycine Max (L.) Merrill) seed quality and the response to molybdenum seed treatment". Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/52010.
Abstract (sommario):
Thesis (MScAgric.)--University of Stellenbosch, 2000.ENGLISH ABSTRACT: Experi!11entsin KwaZulu-Natal showed that seed treatment with molybdenum (Mo) could double the yield and increase the protein content by 1.9% of soybeans grown on acidic soils. However, it was also found that soybean yield at five of the localities was reduced on average by 8% after Mo seed treatment. It was surmised that the yield reductions observed after Mo seed treatment were connected to the quality of the seed used for planting. The aim of this project was to assess the relationship between seed quality and Mo seed treatment and find a fast, easy quality assessment test that could be used to adapt Mo treatments according to seed quality. The first investigation entailed assessing the quality of the seed obtained, from various seed lots, for planting. A number of different seed quality testing techniques were performed and they included the accelerated ageing test, tetrazolium test, conductivity test, standard germination test and an emergence . test planted at different depths with incubation at different temperatures. All the test results were compared with the accelerated ageing test results, to find the test most closely correlated to the accelerated ageing test, which is regarded as the most accurate indicator of soybean seed vigour. It was found that the emergence test where the seeds where planted at 10 cm presented a close correlation with the accelerated ageing test. An assessment of seed quality revealed that the four different seed lots provided seed of three significantly different levels of quality, which could be used for further investigations. The second investigation was concerned with the reaction of the seed of different quality levels to Mo seed treatment. Firstly, seeds from four different seed lots were treated with five different concentrations of Mo and planted under acidic conditions. The establishment was monitored up until six weeks, at which point the experiment was terminated. In the second planting, seeds from the four different seed lots were treated with six different concentrations of Mo and planted under optimum pH conditions. Emergence was monitored and after thinning out the remaining plants were left to mature and produce seed. The emergence percentage results from both of these two plantings did not reveal the alleged positive effect Mo seed treatment has produced in the field and no definite relationship between seed quality and Mo seed treatment was observed. The third investigation was concerned with the effect that osmoconditioning had on the reaction of seed to Mo seed treatment. Seeds from two seed lots, one of very poor quality and the other of good quality, were pre-treated with four different levels of poly-ethylene glycol (PEG 6000) and then treated with four concentrations of Mo. They were planted under optimum pH conditions and establishment was monitored. After being thinned out the remaining plants were allowed to mature and produce seed. The emergence percentage results revealed that the PEG pre-treatments greatly improved emergence percentages, especially in the poor quality seed. There were some positive effects of Mo seed treatment observed where the lower concentrations of Mo were used, but again, no definite relationship between seed quality and Mo seed treatment was found. PEG pre-treatment appeared to help make the seeds more "resistant" to the harmful effects of Mo.
AFRIKAANSE OPSOMMING: Navorsing in KwaZulu-Natal het aangetoon dat saadbehandeling met molibdeen (Mo) die opbrengs van sojabone op suurgrond kan verdubbel en die proteieninhoud met tot 1.9% kan verhoog. Daar is egter ook gevind dat sojaboonopbrengs op vyf lokaliteite met gemiddeld 8% gedaal het na saadbehandeling met Mo. "nVermoede bestaan dat die opbrengsverlagings wat voorgekom het na saadbehandeling met Mo verband hou met die kwaliteit van saad wat vir die aanplantings gebruik is. Die doel van die projek was om vas te stel wat die verband tussen saadkwaliteit en Mo saadbehandeling is en om "n vinnige en maklike toets te vind om saadkwaliteit te bepaal om sodoende Mo behandelings aan te pas volgens saadkwaliteit. In die eerste eksperiment is die kwaliteit van verskillende saadlotte wat verkry is, getoets. "n Aantal verskillende tegnieke om saadkwaliteit te bepaal is uitgevoer. Die tegnieke was die versnelde verouderingstoets, tetrazoliumtoets, konduktiwiteitstoets, standaard ontkiemingstoets en "n vestigingstoets waar saad op verskillende dieptes geplant en by verskillende temperature geïnkubeer is. Die resultate van die verskillende toetse is gekorreleer met die resultate van die versnelde verouderingstoets, wat beskou word as die toets wat die beste aanduiding gee van saadgroeikragtigheid. Daar is gevind dat sade wat 10 cm diep in sand geplant is, se opkoms die beste korrelasie met die versnelde verouderingstoets toon en dus as "n goeie aanduiding van die kwaliteit van saad beskou kan word. Daar is gevind dat daar drie saadlotte is met duidelike kwaliteitsverskille wat gebruik kon word in verdere eksperimente. Die tweede eksperiment het die reaksie van saad van verskillende kwaliteitsvlakke teenoor molibdeen saadbehandeling ondersoek. Eerstens is saad van vier verskillende saadlotte behandel met vyf verskillende konsentrasies Mo en onder baie suur toestande geplant. Die vestiging is gemonitor vir ses weke waarna die eksperiment gestaak is. Daarna is saad van dieselfde vier saadlotte behandel met ses verskillende Mo konsentrasies en onder optimum pH toestande geplant. Vestiging is gemonitor en na ses weke is die plante uitgedun en twee plante per pot is gelaat om saad te produseer. Die ~ vestigingspersentasie van beide die eerste en tweede plantings het nie die verwagte positiewe effek teenoor Mo saadbehandeling getoon nie en geen betekenisvolle verwantskap tussen saadkwaliteit en Mo saadbehandeling kon waargeneem word nie. Die derde eksperiment het die invloed van osmokondisionering op die reaksie van saad op Mo saadbehandeling ondersoek. Saad van twee saadlotte, een van goeie kwaliteit en een van swak kwaliteit, is voorafbehandel met poli-etileen glikol (PEG 6000) en daarna met vier konsentrasies van Mo behandel. Die sade is onder optimum pH toestande geplant en die vestiging is gemonitor. Nadat dit uitgedun is, is die oorblywende twee plante gelaat om saad te produseer. Die vestigingspersentasies het getoon dat PEG voorafbehandelings vestiging betekenisvol verbeter, veral in die geval van lae kwaliteit saad. Daar was 'n . positiewe effek van Mo saadbehandeling waar relatief lae konsentrasies molibdeen toegedien is, maar daar kon weereens nie 'n duidelike verwantskap tussen saadkwaliteit en Mo saadbehandeling waargeneem word nie. Dit blyk dat PEG voorafbehandeling die sade meer bestand teen die skadelike invloed van Mo gemaak het.
10
Chappell, Matthew. "Assessment and Reaction of Triticum aestivum Genotypes to Fusarium graminearum and effects on Traits Related to Grain Yield and Seed Quality". Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/30784.
Abstract (sommario):
Fusarium graminearum (Schwabe), causal organism of fusarium head blight (FHB), has become a major pathogen of wheat (Triticum aestivum L.) throughout North America. Since its discovery in the United States, the disease has spread south and east until at present it is an annual threat for growers of winter wheat in the Mid-Atlantic region. Yield losses for soft red winter (SRW) wheat averaged 908 kg ha-1 in the FHB outbreak of 1998 (Griffey et al., 1999). The economic loss from this single FHB epidemic was an estimated 8.5 million dollars.
Environmental conditions favorable for FHB development, including above average rainfall and temperatures during anthesis, have become more common in the Upper-Midwestern wheat-growing region over the past decade, leading to substantial losses in wheat and barley crops. This, coupled with low prices being paid for wheat, has prompted research toward solving the problem of FHB across the nation. The majority of labor and financial resources devoted to FHB research are dedicated to incorporating FHB resistance into adapted wheat lines. While this is a prudent method of combating this disease, this process will take many years to complete.
We have examined all FHB assessment parameters, which include FHB incidence, FHB severity, FHB index, percentage fusarium damaged kernels (percentage FDK), and 15-acetyl deoxynivalenol toxin (DON toxin) accumulation, to ascertain which assessment parameters best quantify FHB resistance levels in addition to grain yield and grain volume weight (GVW) losses. FHB index provides the most reliable in-field assessment of a genotype's resistance level, whereas percentage FDK provides a reliable measure of a genotype's resistance level post-harvest. FHB index and percentage FDK are also the most predictive assessment parameters with regard to grain yield and GVW loss. A wide range in both level and type of resistance was observed among genotypes examined in this study. The cultivars Agripro Patton, Ernie, INW9824, Roane, and the experimental line NY87048W-7388 consistently had lower scores for FHB assessment parameters and lower losses of grain yield and GVW.Master of Science
11
Pinyosinwat, Anan. "The effect of seed rate on the yield and quality of wheat and its interaction with other agronomic practices". Thesis, University of Reading, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367692.
12
Ijaz, Muhammad [Verfasser]. "Effect of Triazole and Strobilurin fungicides on seed yield and grain quality of winter rapeseed (Brassica napus L.) / Muhammad Ijaz". Gießen : Universitätsbibliothek, 2012. http://d-nb.info/106395522X/34.
13
Asare, Eric. "The effects of nitrogen and sulphur fertilizers on the growth, yield and seed quality of oilseed rape (Brassica napus L.)". Thesis, Imperial College London, 1991. http://hdl.handle.net/10044/1/46652.
14
Mackasmiel, Lucas A. "Assessing the Distribution and Impact of Bean pod mottle virus (BPMV) as a Re-emerging Virus, and Soybean mosaic virus (SMV) in Soybean Grown in Virginia". Diss., Virginia Tech, 2004. http://hdl.handle.net/10919/28836.
Abstract (sommario):
Bean pod mottle virus (BPMV, Genus Comovirus, Family: Comoviridae)is an important virus in soybean (Glycine max (L.) Merrill), causing quality and yield loss due to seed coat mottling and seed weight reduction. Although BPMV has been known in Virginia since 1958 and has always been regarded as causing negligible losses, its impact is changing as BPMV incidence has increased in many soybean growing areas of Virginia and the USA in general. From 1997 to 2001, a total of five BPMV isolates (V-W1, V-W2, V-S98-1, V-S98-15 and V-S01-10) were collected in Virginia and characterized. In this study, the effects of these isolates were studied, alone or with Soybean mosaic virus (SMV, Genus Potyvirus, Family Potyviridae) strain SMV G1, and isolates S98-51 and S98-52, on selected soybean cultivars. Individual isolates of BPMV showed variable symptom severity, and resulted in yield loss of between 40.4 to 58.1%, while SMV caused 23.7% in the most severe interactions. Up to 100% yield loss was realized from double inoculations of selected BPMV and SMV isolates, BPMV V-S98-1 + SMV S98-52 and BPMV S98-15 + SMV S98-52 on Hutcheson and Hutcheson Roundup Ready® (BC5) soybeans, respectively. Time of inoculation, a critical factor in the impact of many virus diseases, affected seed coat mottling in four cultivars and seed weight in two cultivars, in tests with four BPMV isolates and three stages of soybean development. All BPMV isolates inoculated to plants at vegetative stage V1-V3 severely increased seed coat mottling and reduced seed weight than those inoculated at V4-V6 and reproductive stage R1-R3. Seedlings grown from non-mottled seeds germinated more uniformly had fewer thin-stemmed seedlings and grew faster than those grown from mottled seeds. Inoculation of various cultivars and breeding lines showed that there was no correlation between the severity of virus-induced foliar symptoms, relative accumulation of SMV, and extent of seed coat mottling. Thus, by avoiding the presence of BPMV at an early growth stage through proper timing of planting to avoid vectors, proper cultural practices like weed control, use of SMV free seeds, and chemical control, it is possible to greatly improve seed quality and reduce yield losses in soybean.Ph. D.
15
Balole, Thabsile Virginia. "Strategies to improve yield and quality of sweet sorghum as a cash crop for small scale farmers in Botswana". Diss., Pretoria : [s.n.], 2001. http://upetd.up.ac.za/thesis/available/etd-05032002-082332.
16
Cunha, Ricardo Pereira. "Rendimento de sementes de azevém anual BRS Integração em função de desfolha e adubação nitrogenada". Universidade Federal de Pelotas, 2017. http://guaiaca.ufpel.edu.br:8080/handle/prefix/4017.
Abstract (sommario):
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
O azevém anual cultivar BRS Integração, no Sul do Brasil, em solos hidromórficos, diferencia-se dos demais, especialmente por apresentar alta produtividade de forragem de boa qualidade em um ciclo produtivo mais curto. Característica fundamental para a integração com lavouras de estação quente. No entanto, são poucas as informações sobre respostas desta cultivar ao manejo de desfolha e produção de sementes de alta qualidade. Neste sentido, foi conduzido um experimento no Sul do Rio Grande do Sul sobre solos hidromórficos das terras baixas para verificar a influência da frequência, intensidade de desfolha e dose da adubação nitrogenada sobre a produção e a qualidade da semente da cultivar BRS Integração. Foram testadas duas frequências de desfolha (duas e três desfolhas), duas intensidades de desfolha (7,5 e 15cm de altura do resíduo) e, após a última desfolha, foram testados diferentes níveis de adubação nitrogenada (50; 100; 150 e 200kg.ha-1). O delineamento foi em faixas para o fator adubação e os manejos de desfolha foram alocados ao acaso dentro das faixas. Os dados foram submetidos à análise de variância, comparação de médias pelo teste Tukey e regressão polinomial para descrição do fator nitrogênio, ambas ao nível de 5% de probabilidade. A execução da terceira desfolha mantendo 7,5cm de altura residual, prejudica o rendimento e a qualidade fisiológica da semente, bem como, a execução da terceira desfolha mantendo 15cm de altura residual possibilita alto potencial de resposta da planta para a produção de sementes de alta qualidade, desde que suprida a necessidade de nitrogênio.
The annual ryegrass BRS Integration, in the South of Brazil, in hydromorphic soils, differs from the others, especially because it presents high productivity of good quality fodder in a shorter productive cycle. Key feature for integration with hot season crops. However, there is few information on the responses of this cultivar to the management of defoliation and production of high quality seeds. In this sense, an experiment was carried out in the south of Rio Grande do Sul on lowland hydromorphic soils to verify the influence of frequency, defoliation intensity and nitrogen fertilization dose on the production and seed quality of BRS Integration. Two defoliation frequencies (two and three defoliation), two defoliation intensities (7,5 and 15cm height of the residue) were tested and, after the last defoliation, different levels of nitrogen fertilization (50, 100, 150 and 200kg.ha-1). The design was in bands for the fertilization factor and the defoliation maneuvers were randomly allocated within the ranges. The data were submitted to analysis of variance, comparison of means by Tukey test and polynomial regression to describe the nitrogen factor, both at the 5% probability level. The execution of the third defoliation, maintaining 7,5cm of residual height, impairs the yield and the physiological quality of the seed, as well as, the execution of the third defoliation, maintaining 15 cm of residual height, allows high plant response potential for high seed production quality.
17
Šiūpelytė, Vaida. "Priešsėlio poveikio vasarinių kviečių veislių produktyvumui ir sėklų kokybės rodikliams tyrimai". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140616_110632-58487.
Abstract (sommario):
Magistrantūros studijų baigiamajame darbe pateikiami 2013 metų vasarinių kviečių veislių, sėtų po skirtingų priešsėlių, derlingumo ir sėklų kokybės rodiklių duomenys ir atliktas priešsėlių poveikio veislėms įvertinimas.
Darbo objektas - vasariniai kviečiai 'Triso' ir 'Hamlet', sėti po skirtingų priešsėlių (vasarinių miežių ir vasarinių rapsų).
Darbo metodai ir vieta. Tyrimai vykdyti 2013 m. Vilmos Žliobienės ūkyje, Antušavos kaime, Kėdainių rajone. Eksperimento įrengimo vietoje dirvožemis karbonatingas glėjiškas rudžemis (RDg4-k2). Buvo nustatytas grūdų derlingumas, derliaus struktūros komponentai (produktyvių stiebų skaičius, vidutinis grūdų skaičius varpoje, 1000 grūdų masė, varpos produktyvumas). Grūdų kokybės rodikliai (baltymų, šlapiojo glitimo, krakmolo kiekis, sedimentacijos rodiklis ir kiti) nustatyti AB :Linas agro" laboratorijoje.
Darbo rezultatai. Esmingai didžiausias derlingumas (5,9 t ha-1) ir 1000 grūdų masė (43,84 g) nustatyti `Hamlet` veislės vasariniams kviečiams po vasarinių rapsų priešsėlio. Patikimai didžiausias produktyvių stiebų skaičius (432,8 vnt. m-2) ir vidutinis grūdų skaičius varpoje (34,8 vnt.) buvo `Triso` veislės augalų. Genotipo (veislės) savybės ir 1000 grūdų masė turėjo didesnę įtaką grūdų derlingumui ir esmingai padidino ‘Hamlet` veislės derlingumą.
Esmingai didžiausias vasarinių kviečių grūdų baltymų (14,9 proc.) ir sedimentacijos rodiklis (71 proc.) nustatytas ‘Triso‘ veislės grūduose po vasarinių rapsų priešsėlio. Esmingai didžiausias... [toliau žr. visą tekstą]In Master's thesis is a submitted spring wheat variety of 2013, which were sown under different preceding crops, yield and seed quality indicators in data and performed assessment of preceding crop varieties impact. The object. Spring wheat 'Triso' and 'Hamlet', which were sown after different preceding crops (spring barley spring oilseed rape). Working methods and location. Research was carried out in 2013 at Vilmos Žliobienės farm in the Antušavos village in the Kėdainių area. The soil is endohypogleyic cambisol (RDg4-k2) at installation site of the experiment. It was established grain yield, harvest structure components (the number of productive stems, average number of wheat-ear, 1000 grain weight, productivity of wheat-ear). Grain quality indicators (protein, wet gluten, starch content sedimentation rate and others) were determined at AB Linas Agro laboratory. Results. Essentially the highest grain yield (5.9 t ha-1) and 1000 grain weight (43.84 g) were obtained in the fields of `Hamlet` variety, which were sown after spring oilseed rape. Reliably largest number of productive tillers number (432.8 units. m-2) and the average number of grains per ear (34.8 pc) was the variety of `Triso` compared to the variety of `Hamlet`, which was investigated in the same influence of forecrop. But a variety of properties and weight of 1,000 grain had a greater impact on grain yield and substantially increased varieties of 'Hamlet `yield. Substantially the largest spring wheat grain... [to full text]
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Huarachi, Morejon Nancy. "Genetic and Environmental Factors Affecting Improvement of Rootstocks for Tomato". The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1376666605.
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Eicholz, Eberson Diedrich. "Produção de sementes de mamona no sul do Rio Grande do Sul". Universidade Federal de Pelotas, 2009. http://repositorio.ufpel.edu.br/handle/ri/2398.
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Previous issue date: 2009-03-16The success of any agricultural business based in commercial exploitation of plant crops requires the use of high quality seeds, with potential to grow vigorous and high yielding plants in a short period of time. Regarding to castor bean, there are few articles related to seed production in Rio Grande do Sul. This work aimed to study the seed production viability in southern of Rio Grande do Sul. There were carried out experiments in two farms, season of 2006/07, in Canguçu, using IAC 80 and AL Guarany 2002 cultivars, sowed in two different dates (November and December). It was evaluated the agronomic performance of plants in the field and yield components, as well as the physiological and physic quality of seeds from different parts of raceme (divided in three parts) and different raceme-orders. These analyses were conducted at Embrapa Clima Temperado, Pelotas/RS. According to the results, it was observed genotype x environment interaction effects on the yield components and physiological and physic quality of seeds in AL Guarany 2002 e IAC 80 cultivars, considering that the first raceme-order seed position doesn t affect the seeds physiological and physic quality. In AL Guarany 2002 , the seeds from the first and second raceme-order presented quality, with no environment or sowing date influence, meanwhile IAC 80 cultivar showed quality in November sowing, with no environment influence. It is concluded that it is possible to produce seeds with physiological and physic quality of castor bean in southern of Rio Grande do Sul.
O sucesso de qualquer empreendimento agrícola baseado na exploração comercial de cultivos vegetais requer a utilização de sementes de alta qualidade, com potencial de produzir plantas vigorosas e produtivas, de maneira uniforme e no menor tempo possível. Na cultura da mamona (Ricinus communis L.), são poucos os estudos relacionados a produção de sementes no Rio Grande do Sul. O objetivo do trabalho é estudar a viabilidade de produção de sementes, na Região Sul do Rio Grande do Sul. Para tanto foram implantados experimentos em duas propriedades de agricultores familiares na safra 2006/07 no município de Canguçu, utilizou-se as cultivares IAC 80 e AL Guarany 2002 em duas épocas de semeadura (novembro e dezembro). Foi avaliado o desempenho agronômico das cultivares, assim como as sementes provenientes das diferentes ordens e posições de racemo (dividido em três partes), quanto aos componentes do rendimento, qualidade física e fisiológica. As análises foram realizadas na Embrapa Clima Temperado, Pelotas/RS. De acordo com os resultados observou-se efeito da interação genótipo x ambiente nos componentes de rendimento e qualidade da semente para as cultivares AL Guarany 2002 e IAC 80, sendo que a qualidade física e fisiológica não apresenta diferença em função da posição para racemos de primeira ordem. Para cultivar AL Guarany 2002, as sementes dos racemos de primeira e segunda ordem são de melhor qualidade, independente de local e época de semeadura, enquanto que para IAC 80 , as sementes dos racemos de primeira e segunda ordem são de qualidade na semeadura de novembro, independente de local. Conclui-se que é possível produzir vii sementes de mamona de alta qualidade física e fisiológica nas condições do sul do Rio Grande do sul.
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Pino, Mateus. "Desempenho individual e em comunidades de plantas de soja formadas por diferentes proporções de sementes de alto e baixo vigor na linha de cultivo". Universidade Federal de Pelotas, 2013. http://repositorio.ufpel.edu.br/handle/ri/1429.
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Previous issue date: 2013-10-11The objective of this study was to evaluate the influence of low and high vigor of soybean seeds on agronomic characteristics , yield components and seed yield, in individually plants and on the communities of plants generated by different proportions of plants originated from high and low vigor seeds on the crop row. The experiment was conducted in the county of Selbach - RS, in a no-till seeding system over ryegrass straw, in 2012/2013 crop year. Was used the cultivar of soybean FPS Urano RR, of short-cycle. The experiment design was completely randomized, with five replications. Were selected seven different proportion of high and low vigor seed, along the sowing row. Were evaluated agronomic characteristics, yield components and seed yield on plants and on the communities formed. Based on the results obtained it was found that: plants from high vigor seeds show higher than plants arising from low vigor, in V5 and R8 phenological stages; Based on the results obtained it was found that: plants from high vigor seeds show greater height than plants arising from low vigor, in V5 and R8 phenological stages; even when communities are formed only by plants arising from low vigor seeds, these can not reach yield levels found in plants arising from high vigor seeds; number and weight of seeds per plant, are the yield components that more contributed to increase yield; the plant community formed only of plants grown from seeds of high vigor, shows seed yield per area 29% more, comparatively, to one formed only of plants from low vigor seeds.
O objetivo do presente trabalho foi avaliar a influência do alto e baixo vigor de sementes de soja sobre características agronômicas, componentes de rendimento e rendimento de sementes, nas plantas individualmente e nas comunidades de plantas geradas por diferentes proporções de plantas originadas de sementes de alto e baixo vigor dentro da linha de cultivo. O experimento foi conduzido no município de Selbach - RS, com sistema de semeadura direta sobre palhada de azevém, no ano agrícola de 2012/2013. Utilizou-se a cultivar de soja FPS Urano RR, de ciclo precoce. O delineamento experimental foi totalmente casualizado, com cinco repetições. Foram selecionadas sete diferentes proporções de sementes com alto e baixo vigor, ao longo da linha de semeadura. Avaliaram-se características agronômicas, componentes de rendimento e o rendimento das plantas e das comunidades formadas. Com base nos resultados obtidos verificou-se que: plantas originadas de sementes de alto vigor apresentam maior altura nos estádios fenológicos V5 e R8; mesmo que a comunidade seja oriunda apenas de sementes com baixo vigor, essas não conseguem alcançar níveis de produtividade encontrados em plantas originadas de sementes de alto vigor; o número e peso de sementes por planta, são os componentes que mais contribuíram no aumento de rendimento; a comunidade de plantas formada apenas por plantas oriundas de sementes de alto vigor, apresenta rendimento de sementes por área 29% a mais, comparativamente, a uma formada apenas por plantas originadas de sementes de baixo vigor.
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Leite, Ricardo Figueiredo Cavalheiro. "Rendimento e qualidade de sementes de arroz irrigado em função da adubação com boro". Universidade Federal de Pelotas, 2008. http://repositorio.ufpel.edu.br/handle/ri/1491.
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Previous issue date: 2008-04-24Boron is an essential plant nutrient. Its functions are related to cellular growth and flower development. At flowering, the micronutrient deficiency reduces male-fertility due to damage to microsporogenesis and to the pollen tube growth. This work aims to define the phases of higher sensibility of the culture, with the purpose of identifying appropriate times for applying of boron to the rice crop. Boron application, in form of sodium borate (Na2B4O7.10H2O), in dosage of 10 kg.ha, was made in five different phases: base fertilization; tillering; primary flower differentiation; booting stage; and full flowering. Evaluation on yield, sterility and rice yield components, as well as physiological quality of the seeds produced have been done. The results allowed the verification that the amount of sodium borate applied is not harmful to the flooded rice crop, and there are no effects of application of the nutrient in different times of cultivation.
O boro é um nutriente essencial para as plantas. Suas funções estão envolvidas com o crescimento celular e o desenvolvimento da flor. Na floração, a deficiência do micronutriente reduz a macho-fertilidade em função do prejuízo à microesporogênese e ao crescimento do tubo polínico. Neste trabalho, objetivou-se definir as fases de maior sensibilidade da cultura, com o intuito de identificar épocas apropriadas para a aplicação de tratamentos corretivos de boro. A aplicação do boro, na forma de borato de sódio (Na2B4O7.10H2O), na dosagem de 10 kg.ha, foi realizada em cinco épocas diferentes (na base; no perfilhamento; na diferenciação do primórdio floral; no emborrachamento; e na floração plena). Foram realizadas avaliações sobre o rendimento, esterilidade e componentes de rendimento do arroz, bem como sobre a qualidade fisiológica das sementes produzidas. O trabalho pode constatar que a quantidade aplicada de borato de sódio não é prejudicial à cultura do arroz irrigado, embora não haja efeito da aplicação do nutriente em diferentes épocas do cultivo.
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Filho, Carlos Pieta. "Cereal seed development and seed quality". Thesis, University of Reading, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.280316.
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Pieta, Filho Carlos. "Cereal seed development and seed quality". Reading (U.K.), 1991. http://repositorio.ufsc.br/xmlui/handle/123456789/75763.
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Grotenhuis, Timothy P. "Superoptimal CO2 Reduces Seed Yield in Wheat". DigitalCommons@USU, 1996. https://digitalcommons.usu.edu/etd/6747.
Abstract (sommario):
Although projected terrestrial CO2 levels will not reach 1000 μmol moI-1 (0.1%) for many decades, CO2 levels in growth chambers and greenhouses routinely exceed that concentration. CO2 levels in life support systems in space can exceed 10,000 μmol moI-1 (1%) CO2. Numerous studies have examined CO2 effects up to 1000 μmol mol-1, but theoretical and some experimental evidence indicates that the beneficial effects of CO2 continue past 1000 μmol mol-1 and are near-optimal for wheat at about 1200 μmol mol-1.
We studied the effects of near-optimal and superoptimal CO2 levels (>1200 μmol mol-1) on yield of two cultivars of hydroponically grown wheat in 12 trials. Increasing CO2 from suboptimal to near-optimal (350 to 1200 μmol mol-1) increased vegetative growth by 25% and seed yield by 15% in both cultivars. Yield increases were primarily the result of an increased number of heads m-2. Further elevation of CO2 to 2500 μmol mol-1reduced seed yield by 22% in cv. 'Veery-10' and by 15% in cv. 'USU-Apogee'. Superoptimal CO2 did not decrease the number of heads m-2, but reduced seeds per head by 10% and mass per seed by 11%. CO2 toxicity occurred over a wide range of light levels. Subsequent trials revealed that superoptimal CO2 in the 2 weeks before and after anthesis mimicked the effect of constant superoptimal CO2. Furthermore, near-optimal CO2 in the 2 weeks before and after anthesis mimicked the effect of constant near-optimal CO2. Nutrient concentration of leaves and heads was not affected by CO2. The yield decreases may be a response mediated by ethylene.
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Christenson, Brent Scott. "Characterization of soybean seed yield using optimized phenotyping". Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/16030.
Abstract (sommario):
Master of ScienceDepartment of Agronomy
William T. Schapaugh Jr
Crops research moving forward faces many challenges to improve crop performance. In breeding programs, phenotyping has time and economic constraints requiring new phenotyping techniques to be developed to improve selection efficiency and increase germplasm entering the pipeline. The objectives of these studies were to examine the changes in spectral reflectance with soybean breeding from 1923 to 2010, evaluate band regions most significantly contributing to yield estimation, evaluate spectral reflectance data for yield estimation modeling across environments and growth stages and to evaluate the usefulness of spectral data as an optimized phenotyping technique in breeding programs. Twenty maturity group III (MGIII) and twenty maturity group IV (MGIV) soybeans, arranged in a randomized complete block design, were grown in Manhattan, KS in 2011 and 2012. Spectral reflectance data were collected over the growing season in a total of six irrigated and water- stressed environments. Partial least squares and multiple linear regression were used for spectral variable selection and yield estimation model building. Significant differences were found between genotypes for yield and spectral reflectance data, with the visible (VI) having greater differences between genotypes than the near-infrared (NIR). This study found significant correlations with year of release (YOR) in the VI and NIR portions of the spectra, with newer released cultivars tending to have lower reflectance in the VI and high reflectance in the NIR. Spectral reflectance data accounted for a large portion of variability for seed yield between genotypes using the red edge and NIR portions of the spectra. Irrigated environments tended to explain a larger portion of seed yield variability than water-stressed environments. Growth stages most useful for yield estimation was highly dependent upon the environment as well as maturity group. This study found that spectral reflectance data is a good candidate for exploration into optimized phenotyping techniques and with further research and validation datasets, may be a suitable indirect selection technique for breeding programs.
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Marin, Rosidelma da Silva Felicio. "Fósforo na qualidade de sementes de soja e consequente desempenho na produção de grãos". Universidade Federal de Pelotas, 2012. http://repositorio.ufpel.edu.br/handle/ri/1369.
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Previous issue date: 2012-05-22The objective of this study was to evaluate the effect of application different doses of phosphorus in the seed quality and productivity in the next generation. The experiment was conducted in Itiquira, MT, during the harvest 2009/2010 and 2010/2011. In the season 2009/2010, soybean seeds were sown under different doses of phosphorus in the line from the chemical analysis of soil, in the following proportions in accordance with the recommendation: control - 50%, 100%, 150%, 200% of the recommended dose P2O5. Its was used triple superphosphate as phosphorus source. Fertilization with 100 kg/ha of potassium chloride was distributed broadcast post-emergence. After harvesting, it s was analyzed viability and vigor, and yield components as insertion height of the first pod, number of pods per plant, number of seeds per plant, number of plants per meter, yield and mineral in the seed. Part of the seed was stored with 13% humidity under controlled temperature between 20° and 22°C. In 2010/2011, harvesting the seeds from each treatment for 2009/2010 crop were sown in the field, receiving fertilizer as soil analysis. The floor area for each treatment was 270 m². After the harvesting treatments in the second year, it was evaluated the yield. The experimental design was from blocks at random with five replicates. The average were submitted to analysis of variance. Subsequently subjected to Dunnett's test and polynomial regression. The seeds with higher phosphorus levels influence positively the number of seeds and pods per plant, contributing to the increase of soybean yield. Higher phosphorus concentrations in the line of sowing improve soybean seeds vigor, also they contribute to the increase of phosphorus, iron and zinc of seeds produced, however, manganese concentrations are reduced.
O objetivo do presente trabalho foi avaliar o efeito da aplicação de diferentes doses de fósforo na qualidade fisiológica da semente, bem como a produtividade na geração seguinte. O experimento foi conduzido em Itiquira, MT, nas safras 2009/2010 e 2010/2011. Na safra 2009/2010, as sementes de soja foram semeadas sob diferentes doses de fósforo na linha a partir da análise química do solo, nas seguintes proporções, de acordo com a recomendação: controle - 0%, 50%, 100%, 150% e 200% da dose de P2O5 recomendada. A fonte de fósforo utilizada foi superfosfato triplo. A adubação de cobertura com 100 kg/há de cloreto de potássio foi distribuída a lanço em pós-emergência. Após a colheita, foram analisados a viabilidade e o vigor das sementes, além dos componentes do rendimento, como altura de inserção do primeiro legume, número de legumes por planta, número de sementes por planta, número de plantas por metro, produtividade e nutrientes minerais na semente. Parte da semente foi armazenada com umidade de 13%, em condições controladas de temperatura entre 20° e 22º. Na safra 2010/2011, as sementes provenientes de cada tratamento da safra 2009/2010 foram semeadas em campo, recebendo adubação conforme análise de solo. A área útil para cada tratamento foi de 270 m². Após a colheita dos tratamentos, no segundo ano, avaliouse a produtividade da cultura. O delineamento experimental foi de blocos ao acaso, com cinco repetições. As médias foram submetidas à análise de variância e, posteriormente, submetidas ao teste de Dunnett e regressão polinomial. Sementes com teores superiores de fósforo influenciam positivamente o número de sementes e de legumes por planta, contribuindo para o aumento de produtividade da soja. Concentrações maiores de fósforo na linha de semeadura melhoram o vigor das sementes de soja, além de contribuir para o aumento de fósforo, ferro e zinco das sementes produzidas. No entanto, as concentrações de manganês são reduzidas
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Hughes, Rhiannon. "Determinants of seed size and yield in Arabidopsis thaliana". Thesis, University of Bath, 2009. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.519024.
Abstract (sommario):
It is becoming increasingly important to improve the yield of seed crops to feed an expanding population and, more recently, to cope with additional strains on food-oriented agriculture posed by biofuel production and global climate change. One strategy to increase yield is to increase seed size. However in nature, due to the limited resources of the mother plant, an enlarged seed size is often associated with a concomitant reduction in seed number. Using the model plant Arabidopsis thaliana, a biotechnological approach to increase seed size through the modification of the triploid endosperm or the ovule integuments was shown to be a viable strategy to improve seed yield. Targeted over-expression of the ANT transcription factor specifically within the endosperm significantly increased seed size without negative effects on fertility. Overcoming compromised fertility in arf2 mutants established that ARF2 and the integuments are important factors in determining seed size and yield. To ensure agronomic relevance, both the gross yield and the harvest index (HI, ratio of seed yield to biological yield) were used to assess the impact of traits, such as increased integument size, introduced into Arabidopsis. To uncover novel regulators of seed size and further develop the current understanding of seed development, second-site mutations were induced in the auxin response factor 2 (arf2) mutant, which produces large seeds due to extra cell division in the ovule integuments. The ARABIDOPSIS CRINKLY 4 (ACR4) gene was identified as a suppressor of the arf2 seed phenotype. In arf2-8 acr4 double mutants, an additive effect on cell proliferation was observed, indicating that ACR4 affects the seed coat through a developmental pathway independent of ARF2. Natural variation present in Arabidopsis was used to study seed yield and its components. Considerable variation in seed size, yield and HI was revealed. Significantly, high seed weight was not associated with high yield or high HI. In contrast, high seed number and reduced plant stature were revealed as important components of high yield and yield efficiency. Additionally, ERECTA was identified as a potential ‘Green Revolution’ gene. Seed size in Arabidopsis was shown to be an extremely plastic trait in response to alterations in the post-flowering source-sink ratio, increasing by 35.0 – 66.2% in the ecotypes tested. Furthermore, a difference in seed weight between restricted (high source-sink ratio) and unrestricted (low source-sink ratio) pollinations was first observed remarkably early in seed development. However, reducing seed number by restricting pollination did not substantially alter integument or endosperm development in order to facilitate increased nutrient uptake.
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MARIN, MARIA. "Improving seed quality in large-scale production of native seed". Doctoral thesis, Università degli studi di Pavia, 2017. http://hdl.handle.net/11571/1214854.
Abstract (sommario):
The use of native species has been increasingly advocated to achieve the sustainable recovery of degraded areas and in Europe considerable effort has also been invested into grassland restoration using such species. However, little attention has been paid to the evaluation and significance of aspects of the seed quality of native species, which may have implications for the success of these projects. The current research examined three aspects of seed quality in the context of commercial seed production and the use of seed in the restoration of vegetation. Firstly, the effect of plant and seed responses to a range of maternal environments during seed production was examined using the perennial herb Primula vulgaris as a model. Different shading conditions, imposed in the field over two seasons during seed maturation, produced a range of red : far-red light ratios (R:FR) received by the parent plants. The competitiveness of P. vulgaris plants grown in the different environments was evaluated though measurements of plant gas exchange, membrane integrity, leaf chlorophyll concentration, photosynthetic efficiency, specific leaf area and above ground plant biomass; the weight and number of seeds produced was also assessed. This revealed the phenotypic plasticity of P. vulgaris and that growth, competitiveness and seed production were favoured in shaded conditions. Subsequent germination of the harvested seeds at five temperatures (5 – 25oC) and high to low R:FR revealed that there was no effect of shading of the maternal plant on seed quality, either the rate of germination or final germination. In addition, the maternal environment did not affect the subsequent light and temperature requirements for germination. An increased germination capacity in response to a higher R:FR for all maternal environments suggested the potential for seedling establishment under vegetative shade only in the presence of canopy gaps. Secondly, the germination potential and dormancy-breaking requirements of 113 commercially available seed lots of eight European native species was examined. This revealed a wide range in the germination of seed lots within a species and surprisingly low levels of dormancy. Alternative and more rapid methods to the routine germination methods were subsequently developed. A tetrazolium testing protocol was developed that predicted germination of each of the eight native species in only two days. In addition, the electrical conductivity (EC) of seed soak water provided a quick and inexpensive measure of final germination in a day and even within a day. However, its application may be limited to large and exalbuminous seeds, such as Cyanus segetum, which are dominated by the embryo and lack an endosperm. The third aspect of seed quality investigated was its impact on establishment and growth of Rhinanthus minor, a hemi-parasite. Ten seed lots from commercial sources were sown in the field and their germination characteristics were investigated in the laboratory. Field emergence was influenced by both the radicle emergence of each lot and the mean germination time, which is indicative of seed vigour. Seeds from four lots with >90% radicle emergence were then germinated to radicle emergence and sown in pots alongside plants of two host species, Lotus corniculatus and Holcus lanatus. Plant establishment, height and flowering density were evaluated for the hemi-parasite, while plant biomass was measured for both R. minor and its host. A longer lag period (lower vigour) was associated with higher levels of seedling mortality and lower plant vigour, in terms of plant height and biomass accumulation, and was also reflected in the parasitic impact of the seed lots, with the least vigorous seed lot having no impact on the biomass of its host, Lotus corniculatus. These observations highlight that the quality of the seed is significant to the potential use of R. minor as a hemi-parasite.
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Menegaz, Winícius. "Taxa de multiplicação de sementes de soja em baixa densidade". Universidade Federal de Pelotas, 2014. http://repositorio.ufpel.edu.br:8080/handle/prefix/3201.
Abstract (sommario):
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A máxima produtividade das cultivares de soja é definida pela interação entre a planta, o ambiente de produção e o manejo, essa interação é específica de cada cultivar e seu uso é determinante para atingir o objetivo proposto. Dentre as práticas de manejo, o momento ideal de semeadura, o tipo de solo, a região, a escolha do cultivar, o espaçamento e a densidade de semeadura são fatores que influenciam diretamente a produtividade das plantas e os componentes de rendimento. O fator densidade de semeadura é determinante para atingir o stand de plantas no ambiente de produção, e este, tem influencia direta no crescimento da soja. O objetivo deste trabalho foi avaliar o efeito da densidade de semeadura nos componentes de rendimento, na produção e na qualidade fisiológica de sementes de soja. O delineamento experimental foi de blocos ao acaso. Os tratamentos foram constituídos de cinco densidades de semeadura de 35, 50, 65, 80, 95 e 110mil plantas por hectare, com quatro repetições totalizando 24 parcelas. Cada parcela foi composta por 6 linhas de 3 m de comprimento cada, com espaçamento de 0,5 m. Utilizou-se a cultivar BMX POTENCIA RR, de ciclo precoce e hábito de crescimento indeterminado. A produção de sementes de soja em baixa densidade é viável sem comprometimento na qualidade fisiológica das sementes produzidas. A redução na densidade de semeadura provoca redução na altura de inserção da primeira vagem e aumento no número de ramos laterais e legumes com duas e três sementes. A maior produção de sementes por planta em baixas densidades não compensa a produção por área obtida em densidades próximo do ideal. A cada aumento de 15 mil plantas por hectare há incremento de até 6,7 sacas nas densidades estudadas porém o fator de multiplicação de sementes é diminuído em 9%.
The maximum productivity of soybean is defined by the interaction between the plant, the production environment and management, this interaction is specific for each cultivar, and its use is crucial to achieve the proposed objective. Among the management practices, the ideal time of sowing, the soil, the region, the choice of cultivar, spacing and seeding rate are factors that directly influence plant yield and its yield components. The seeding density factor is crucial to achieve the stand of plants in the production environment and this has a direct influence on the growth of soybean. The objective of this study was to evaluate the effect of planting density on yield components, production and physiological quality of soybean seeds. The experimental design was a randomized block design. Treatments were five sowing densities of 35, 50, 65, 80, 95 and 110 thousand plants per hectare, with four replicates. Each plot consisted of 6 rows of 3 m long, spaced 0.5 m. It was used the cultivar BMX POTENCIA RR, medium maturity and indeterminate growth habit. The physiological quality of seed produced in low density of sowing was no reduced. The reduction in seeding rate causes a reduction in the height of the first pod and increase in the number of lateral branches and the number of legumes with two or three seeds. The highest seed yield per plant at low densities does not compensate for the production obtained at densities close to the ideal. In the increase of 15 thousand plants per hectare there is an increase up to 400 kg, in densities studied.
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Goszka, Abigail R. "Seed Production and Seed Quality in Red Maple (Acer rubrum L.)". Ohio University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1564752025178858.
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Ndirangu, Christopher Mwangi. "Soybean seed yield and size as influenced by row spacing and seeding rate and seed-size heritability". Diss., This resource online, 1997. http://scholar.lib.vt.edu/theses/available/etd-10052007-143343/.
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Hofmann, Wallace C., David L. Kittock, B. Brooks Taylor, Peter T. Else, Joel Malcuit e Carl Michaud. "Emergence and Yield from Six Seed Densities of DPL 90 Cotton". College of Agriculture, University of Arizona (Tucson, AZ), 1985. http://hdl.handle.net/10150/204031.
33
Demir, Ibrahim. "Changes in seed quality during seed development in pepper, tomato and marrow". Thesis, University of Reading, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.304497.
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Moussavi-Nik, Mohsen. "Seed quality and crop establishment in wheat". Title page, contents and abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phm933.pdf.
Abstract (sommario):
Bibliography: leaves 247-268. A series of laboratory, greenhouse and field experiments were conducted to investigate aspects of seed quality in a range of bread wheat genotypes important in South Australia as well as a durum cultivar, Yallaroi. It was concluded that sound healthy seed does vary in quality and this affects seedling vigour, crop establishment and grain yield. Seed source can affect genotype performance in evaluation trials. There is genetic variability for embryo size, coleoptile length, nutrient efficiency and nutrient loading in to the seed which can be exploited by breeders. Agronomically, seed quality can be improved by managing seed crops to aid accumulation of mineral nutrients in the seed and then selecting, by grading, only large seed for sowing.
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Basu, Krishna Rachel. "Improving seed quality in winter oilseed rape". Thesis, University of Nottingham, 2003. http://eprints.nottingham.ac.uk/31239/.
Abstract (sommario):
The majority of UK oilseed rape (Brassica napus L.) is September-sown on heavy clay soils where straw has been incorporated following the cereal harvest in August. A series of germination, emergence and field experiments was conducted to assess the effects of variation in seed quality on establishment and to evaluate the improvements possible by mother crop nitrogen management and pre-sowing seed treatments on commercial and farm-saved seedlots. In germination experiments designed to examme the performance of commercial seed lots at temperatures ranging between 5 and 25°C significant differences were recorded in the speed and unifonnity of germination, particularly at 10 and 15°C, which are comparable to UK field temperatures in late-August to September. The analysis of Apex variety seeds grown from nitrogen-managed mother crops in 1996 and 1998 showed a negative correlation between their nitrogen and oil percentage, which was significantly affected by both the amount (kg ha -1) and timing (vegetative growth period or flowering period) of nitrogen application. The highest nitrogen seeds were produced from mother crops that had received medium (160 kg ha -1) amounts of nitrogen fertiliser during the flowering period. Seeds that were harvested from pods taken from the lower < 1.5 m) section of the crop canopy also had a significantly higher nitrogen and significantly lower oil percentage than those taken from the upper (> 1.5 m) section of the canopy. In germination and emergence experiments the highest nitrogen (3.46 to 3.61 %) seeds germinated significantly faster than the seeds of lowest nitrogen (2.30 to 2.95%) content but they did not emerge as well as low nitrogen seeds from depth. Selecting small (< 2 mm diameter) seeds over large (> 2 mm diameter) seeds significantly improved the rate of geTI11ination and emergence and the final percentage emergence at 10 mm sowing depth although the final percentage emergence at 20 mm sowing depth was significantly greater from the large seeds. Hydrating seeds in water for 18 hours at 15 grad. C before drying them back in the laboratory at 20 grad. C significantly improved the speed of germination and the speed and final percentage emergence at 10 mm sowing depth compared with control treatments provided that the radicle had not emerged before drying back; small seeds derived the most benefit from hydration. Seed heat treatment at temperatures of 80 grad. C significantly delayed the onset of germination and emergence but significantly hastened field establishment. The effects of seed nitrogen percentage, seed size and heat treatment on seedling emergence and subsequent plant growth and development were examined in the field between October 1999 and July 2000. Growth analyses, which were performed in February (growth phase), May (flowering) and July (pre-harvest), showed that the high nitrogen, large seeded and heat-treated populations had a significantly lower rate of plant loss than the low nitrogen, small seeded and control populations. Under field conditions, the higher growth rates and growth parameters of the seedlings produced from the high nitrogen and! or large seeds were not always significant nor were they consistently maintained until harvest. Large seed size and heat treatment significantly increased the number of established plants per m2 and significantly increased the initial plant size. The final yield was not significantly affected by seed nitrogen percentage, seed size or seed heat treatment.
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Nel, Andries Abraham. "Determinants of sunflower seed quality for processing". Diss., Pretoria : [s.n.], 2001. http://upetd.up.ac.za/thesis/available/etd-09012001-132144.
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Keep, Nathan R. "Characterization of physiological parameters in soybean with genetic improvement in seed yield". Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/15621.
Abstract (sommario):
Master of ScienceDepartment of Agronomy
William T. Schapaugh
Recent results from a genetic gain study have illustrated the contribution of plant breeding to the improvement in seed yield of soybean (Glycine max (L.) Merr.). The objective of this research was to characterize the changes in several physiological parameters that have occurred in the released cultivars with improvement of seed yield. Sixty maturity group III and 54 maturity group IV cultivars, released from the 1920's through 2010, were evaluated in dryland and irrigated environments at Manhattan, KS in 2010 and 2011. Genotypes were planted in four-row plots, 3.4 m long, spaced 76 cm apart, arranged in a randomized complete block design with four replications. Genotypes were evaluated for canopy temperature, leaf chlorophyll content, pollen germination, leaf chlorophyll fluorescence, leaf antioxidants, and yield components. Canopy temperature measurements were captured between 1000h and 1400h using an infrared camera multiple times from R1 continuing through R6. Leaf chlorophyll content was measured using a SPAD meter several times from R1 through R6. In vitro pollen germination was measured using incubation temperatures of 28 and 34° C, beginning at late R1 through the end of flowering. Leaf chlorophyll fluorescence was measured beginning at R1 through R6. Leaf antioxidants were analyzed for total antioxidant capacity and electrolyte leakage by collecting leaves from the top 3rd to 5th trifoliate at R4 and R6. Yield components were analyzed from a hand harvested 0.33 m section of one border row. Genotypes differed significantly for canopy temperature, leaf chlorophyll content, pollen germination, and yield components. No significant differences were found for leaf chlorophyll fluorescence or leaf antioxidants. Seed yield increased with year of release. Canopy temperature was negatively correlated and leaf chlorophyll content was positively correlated with year of release in both maturity groups. No significant correlation with year of release was found for in vitro pollen germination or electrolyte leakage. Leaf chlorophyll fluorescence, yield components, and total antioxidant capacity was positively correlated in the maturity group IV genotypes with year of release. Evaluation of these parameters may serve as a basis to select for seed yield, or to assess the abiotic stress tolerance of a genotype.
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Hofmann, W. C., D. L. Kittock, J. Malcuit, P. Else e C. Michaud. "Seedling Emergence and Lint Yield of DP-90 Seed of Different Densities". College of Agriculture, University of Arizona (Tucson, AZ), 1986. http://hdl.handle.net/10150/219729.
Abstract (sommario):
The 1985 and 1986 Cotton Reports have the same publication and P-Series numbers.Six lots of Deltapine (DP) 90 of different seed densities were planted at three planting rates in four tests in Arizona in 1985. The lowest density seed lot had significantly lower standard germination, cold test germination, field emergence, and lint yield than other seed lots. The highest density seed lot had slightly higher lint yield and field emergence than other lots on an average.
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Zanakis, George N. "Changes in seed quality of soyabean (Glycine max) during seed production and storage". Thesis, University of Reading, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316161.
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Rossi, Rubiana Falopa 1986. "Towards understanding the influence of seed maturation on physiological seed quality in legumes /". Botucatu, 2016. http://hdl.handle.net/11449/144406.
Abstract (sommario):
Orientador: Edvaldo Aparecido Amaral da SilvaCoorientador: Olivier Henri Leon Leprince
Banca: José Marcio Rocha Faria
Banca: Julia Buitink.
Banca: Nathalie Nesi
Resumo: Durante a maturação da semente, a germinação, a tolerância à dessecação e a longevidade são adquiridos sequencialmente. A maturação da semente termina com a fase de dessecação que traz o embrião a um estado de repouso. Na cadeia de produção de sementes, o estádio de maturação no momento da colheita é o primeiro fator que influencia a longevidade das sementes e estabelecimento da cultura. Após a colheita, as sementes são normalmente secas para um teor de água compatível com os tratamentos pós-colheita e armazenamento a longo prazo. No entanto, há uma falta de compreensão de como a longevidade das sementes é adquirida durante a maturação da semente e qual o impacto da secagem prematura na longevidade e na retomada das atividades celulares durante a embebição. Esta questão foi abordada aqui, comparando alterações transcriptoma associados com a secagem maturação e embebição de sementes de soja e Medicago truncatula, colhidos em um estádio imaturo e estádio seco maturo. A fase imatura correspondeu final de enchimento de grãos, quando a longevidade não foi adquirida enquanto outros traços de vigor foram adquiridos. A caracterização do transcriptoma de soja revelou que a secagem forçada não era semelhante à maturação de secagem na planta, o que estimulou a degradação da clorofila e síntese de chaperones de proteção. Oitenta e nove % dos genes diferencialmente expressos durante um período de 18 horas de embebição mostrou um padrão similar entre as sementes imaturos e maduros, consist... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: During seed maturation, germination, desiccation tolerance and longevity are acquired sequentially. Seed maturation is terminated by a desiccation phase that brings the embryo to a quiescent state. In the seed production chain, the stage of maturity at harvest is the first factor that influences seed longevity and crop establishment. After harvest, seeds are usually dried to water content compatible with long term storage and post-harvest treatments. However, there is a lack of understanding of how seed longevity is acquired during seed maturation and how premature drying impacts longevity and resumption of cellular activities during imbibition. This was addressed here by comparing transcriptome changes associated with maturation drying and imbibition of seeds of soybean and Medicago truncatula, harvested at an immature stage and mature dry stage. The immature stage corresponded to end of seed filling when longevity was not acquired while other vigor traits were acquired. Transcriptome characterization in soybean revealed that enforced drying was not similar to maturation drying in planta, which stimulated degradation of chlorophyll and synthesis of protective chaperones. Eighty-nine % of the differentially expressed genes during a 18h-imbibition period showed a similar pattern between immature and mature seeds, consistent with a comparable germination between stages. An analysis of the 147 transcripts that increased during imbibition of mature seeds but not in immature seeds... (Complete abstract click electronic access below)
Resumen: Pendant la maturation des graines, la germination, tolérance à la dessication et longévité sont acquises de manière séquentielle. La maturation s'achève par la dessication qui amène l'embryon à l'état de quiescence. Au cours de leur production, la maturité des graines à la récolte est le premier facteur qui influence la longévité et l'établissement de la culture lors du semis. Les graines récoltées sont ensuite séchées à une teneur en eau permettant leur conservation. On ne comprend pas comment la longévité est installée pendant la maturation et comment un séchage prématuré influence la longévité et la reprise des activités cellulaires pendant l'imbibition. L'objectif de la thèse était de répondre à ces questions en comparant les transcriptomes de graines immatures et matures de soja et Medicago truncatula pendant la dessication et l'imbibition. Les graines immatures furent récoltées après le remplissage avant la dessiccation, lorsque la longévité n'est pas encore acquise. Chez le soja, la comparaison des transcriptomes des graines immatures et matures montre que le séchage forcé n'est pas identique à la dessication in planta qui se caractérise par la synthèse de protéines chaperones. Plus de 89% des gènes différentiellement exprimés après 18 h d'imbibition présentent des profils d'expression identiques dans les graines immatures et matures, en accord avec la germination comparable de celles-ci. L'analyse des transcrits dont la teneur augmente uniquement pendant l'imbibition... (Resumen completo clicar acceso eletrônico abajo)
Doutor
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Dillon, Kevin Alan. "Double-Crop Soybean Vegetative Growth, Seed Yield, and Yield Component Response to Agronomic Inputs in the Mid-Atlantic, USA". Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/49380.
Abstract (sommario):
Maximizing productivity and profitability are the primary reasons for double-cropping soybean with small grain in the Mid-Atlantic, USA. Reduced double-crop yield can be attributed to: delayed planting that results in a shortened growing season and less vegetative growth; later-maturing cultivars that terminate main stem growth after flowering and have less growth and nodes; less soil moisture and plant-available nutrients due to small grain uptake; greater air and soil temperatures during vegetative stages that reduce early-season growth; and more favorable conditions for disease development during pod and seed formation. Field experiments were conducted in 2012 and 2013 in eastern Virginia to 1) evaluate cultivar stem growth habit, seeding rate, seed-applied inoculant, starter nitrogen (N) applied at planting, and foliar fungicide on soybean vegetative growth, total N uptake (TNU), seed yield and quality, and yield components; 2) determine the effect of starter N rate, applied with and without inoculant, on soybean vegetative growth, TNU, seed yield and quality, and yield components; and 3) evaluate the response of maturity group (MG) IV and V soybean cultivars to foliar fungicide.
Greater seeding rates, inoculant, N, and fungicide typically were not required together to increase yield. Although cultivar interacted with other factors, early-maturing indeterminate 95Y01 yielded more than late-maturing determinate 95Y20 at 4 of 6 locations. Seeding rate interacted with other factors, but the greater seeding rate increased MG IV yield at 1 of 6 locations and decreased MG V yield at 2 of 6 locations. Starter N increased seed yield by 6 kg ha-1 per kg N applied until yield plateaued at 16 kg N ha-1, which continued to 31 kg N ha-1. When N rate was increased greater than 31 kg N ha-1, yield decreased. Fungicide increased yield for MG IV and V cultivars at 4 of 6 and 3 of 6 locations, respectively and prevented yield loss via mid- to late-season disease control, delayed leaf drop, and greater seed size. Optimum fungicide timing depended on environment and disease development. These data assisted in understanding agronomic inputs' combined or individual effects on double-crop soybean growth, canopy, N uptake, seed yield, and yield components.Ph. D.
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Delamare, Jeremy. "Analyses de deux stratégies d’acclimatation à un stress thermique intense reposant sur une thermo-sensibilisation ou une sensibilisation médiée par des bactéries PGPR chez le colza et la caméline". Electronic Thesis or Diss., Normandie, 2023. http://www.theses.fr/2023NORMC243.
Abstract (sommario):
Le changement climatique auquel nous sommes confrontés est caractérisé notamment par une modification des profils thermiques en termes d’intensité, de durée et de répétition des vagues de chaleur. Ces vagues de chaleur surviennent lors des stades reproducteurs des plantes qui sont également les plus critiques pour l’élaboration des composantes de rendement et des critères de qualité grainière des grandes cultures. Les oléagineux tels que le colza et la caméline sont des espèces particulièrement impactées par le stress thermique, causant de fortes pertes de rendement et une diminution de la qualité grainière. Ainsi, il est nécessaire d’identifier de nouveaux leviers d’acclimatation, telles que des stratégies reposant sur l’acclimatation des plantes. Le thermopriming consistant à préparer les plantes à répondre de façon plus rapide, efficace, intense et/ou sensible à un stress thermique par une exposition préalable à un stress de même nature pourrait permettre d’acclimater les plantes qui mettraient en place des mécanismes de réponses adaptés. L’inoculation des plantes avec des PGPR est un levier d’acclimatation de plus en plus étudié, qui permet de limiter les impacts du stress thermique. Cependant, bien que ces deux types de stratégies d’acclimatation soient principalement étudiés pour limiter l’impact des stress sur le développement des parties aériennes et sur le rendement, peu d’études se sont intéressées à leurs effets sur la morphologie et les fonctions racinaires comme l’exsudation racinaire. Dans le cadre de cette thèse, nous avons analysé chez le colza et la caméline (i) d’une part les effets d’une augmentation graduelle de température précédant un stress thermique, sur le rendement et la qualité grainière et sur la morphologie et l’exsudation racinaire et (ii) d’autre part les effets de l’inoculation de deux Pseudomonas présentant des activités PGPR afin de limiter les impacts du stress thermique sur le rendement et la qualité grainière. De plus, afin de connaitre l’impact du stress thermique et de l’inoculation de PGPR (combinés ou non) sur la plante et la rhizosphère associée, les effets de ces traitements ont été étudiés sur l’exsudation racinaire, l’allocation de carbone (C) dans le système sol-plante, les traits morphologiques racinaires et les communautés microbiennes du sol. Nos résultats ont montré que le colza et la caméline présentent des stratégies contrastées quant à leur réponse au stress thermique. En effet, la caméline semble réagir au stress en augmentant son investissement dans les parties racinaires, en améliorant qualitativement son exsudation et en stimulant l’activité des communautés microbiennes à l’inverse du colza qui semble plutôt endurer le stress. De plus, ces deux espèces ont réagi différemment aux deux stratégies d’acclimatation appliquées. En effet, chez le colza, le thermopriming a permis de diminuer l’exsudation en C et de maintenir son rendement et sa qualité grainière alors qu’il a eu un impact plus négatif sur l’exsudation et la morphologie racinaire chez la caméline. L’inoculation des PGPR est une stratégie d’acclimatation qui tend à limiter les effets du stress thermique sur le rendement et la qualité grainière chez le colza. Cependant, les PGPR agissent comme un puits supplémentaire chez le colza impactant son développement, son exsudation ainsi que l’activité et la composition des communautés microbienne. A l’inverse, la caméline est peu impactée par l’apport de PGPR et semble par conséquent piloter les interactions plante/bactéries plutôt que les subir. En résumé, ces leviers d’acclimatation semblent démontrer des effets bénéfiques pour les plantes. De plus, il pourrait être intéressant d’intégrer les effets de la sélection variétale sur les stratégies de réponses des plantes face au stress et notamment la variabilité des fonctions racinaires et des interactions avec la rhizosphère, à la lumière de la sélection variétale différentiellement subie par le colza et la camélineThe on-going climate changes that we are facing are characterized in particular by modifications of temperature profiles in terms of intensity, duration and repetition of heat waves. These heat waves occur during the reproductive stages of the crops, which are also the most critical for seed yield elaboration and grain quality in crops. Oleaginous species such as rapeseed and camelina, are species particularly impacted by heat stress that cause yield penalties and a lower seed quality. Therefore, to cope with heat stress, it has become necessary to identify new acclimation levers that differ avec genetic and agronomic levers, such as strategies based on plants acclimation. Thermopriming which consist in priming the plants in a way to help them respond more rapidly, effectively, intensively and/or sensitively to heat by a prior exposure of a stress of the same nature could allow the plants to acclimate and develop appropriate response mechanisms. The plant inoculation with Plant Growth Promoting Rhizobacteria (PGPR)-type bacteria is also an acclimation lever increasingly studied, that limit the impacts of abiotic stress such as heat stress. However, although these two types of acclimation levers are mainly studied to limit stress impact on aboveground development and yield, few studies have observed their effects on root morphology and functions such as root exudation. In this thesis we analysed in rapeseed and camelina (i) the effects of a gradual increase in temperature prior a heat stress on yield and grain quality and on root morphology and exudation and (ii) the effects of inoculating two Pseudomonas with PGPR activities in order to limit the impact of heat stress on yield and grain quality. Moreover, in order to understand the impact of heat stress and PGPR inoculation (combined or not) on the plant and associated rhizosphere, the effects of these treatments were studied on root exudation, carbon (C) allocation in the soil-plant system, root morphological traits and soil microbial communities. Our results showed that rapeseed and camelina have contrasting strategies in terms of response to heat stress. Indeed, camelina seems to respond to the stress by increasing its investment to the roots thus improving the quality of exudation and stimulating the activity of microbial communities, unlike rapeseed, which seems to undergo heat stress. In addition, these two species respond differently to the two acclimation strategies applied. In rapeseed, thermopriming reduced C exudation and maintained yield and grain quality, whereas it had a more negative impact on exudation and root morphology in camelina. PGPR inoculation is an acclimation strategy that tends to limit the effects of heat stress on yield and grain quality in rapeseed. However, PGPRs act as an additional sink in rapeseed, impacting its development, exudation and the activity and composition of microbial communities in the rhizosphere. By contrast, camelina is slightly affected by the addition of PGPRs and seems to control the plant/bacteria interactions rather than be affected by them. In short, beneficial effects on plants of these acclimation levers have been evidenced. In addition, it could be interesting to integrate the effects of varietal selection on plant response strategies to stress, and in particular the variability of root functions and interactions with the rhizosphere, in the light of the varietal selection differentially undergone by rapeseed and camelina
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Doonan, Gregory Lynn. "Cyst nematode resistance and seed yield of soybean lines derived from SS97-6946". [Ames, Iowa : Iowa State University], 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1470015.
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Mohamed, Osman Ahmed Ali. "Genetic and physiological studies of flowering and seed yield in Vicia faba L". Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/46452.
45
Maxwell, Brett A. "Effects of Herbicides on Industrial Hemp (Cannabis Sativa) Phytotoxicity, Biomass, and Seed Yield". TopSCHOLAR®, 2016. http://digitalcommons.wku.edu/theses/1742.
Abstract (sommario):
Field studies were established in 2015 at Bowling Green and Lexington, KY to evaluate industrial hemp (Cannabis sativa) tolerance to various herbicides. Hemp was planted into conventionally tilled soils in mid to late June at a seeding rate of 39 kg/ha in Bowling Green and 22 kg/ha in Lexington. Five herbicide active ingredients were applied preemergence (PRE) the day of planting and six postemergence (POST) treatments were applied to 30 cm hemp with a CO2-backpack sprayer delivering 140 L/ha. Plots were 3.1 m wide by 6.1 m long and were sprayed with a 2.1 m boom sprayer leaving a 0.46 m visual check on either side of the sprayed area. A weed free check and a non-treated control were included and all treatments were replicated four times in a randomized complete block design.
Hemp phytotoxicity was evaluated at 14 days after treatment for both PREs and POSTs. Hemp above-ground biomass, weed above-ground biomass, and seed yield were also evaluated. PRE herbicides did not injure hemp as much as POST herbicides, especially at the Bowling Green location. Mesotrione was the most injurious PRE evaluated (> 90%) while bromoxynil and MSMA applications resulted in low phytotoxicity (< 15%). Above-ground biomass was higher in the PRE treated plots, with the exceptions of bromoxynil and MSMA. Weed above-ground biomass was higher in the POST treated plots with the exception of mesotrione. At Bowling Green, PRE herbicides resulted in comparable yields to the weed-free check, except mesotrione. Metolachlor increased seed yield compared to the weed-free check and MSMA and bromoxynil had comparable yields to the weed-free check at both locations. Results identified possible herbicides to include in a future integrated pest management weed control program for industrial hemp.
46
Kilby, Christopher. "Evaluation of yield component changes in Australian cotton cultivars". Thesis, Faculty of Agriculture, Food & Natural Resources, 2006. http://hdl.handle.net/2123/914.
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Elder, Kurt David. "Cultural Thinning of Native Sagebrush Stands to Increase Seed Yields". BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3441.
Abstract (sommario):
Wyoming big sagebrush (Artemisia tridentata Nutt.) is an important native shrub in the Great Basin because of its wide distribution where it dominates over 60 million ha and provides essential habitat and forage for many varied species. The hand collection of sagebrush seed often results in seed scarcity and the available seed quantities are at times inadequate to revegetate large areas that have been disturbed, resulting in a demand for sagebrush seed. Study locations were selected near Scipio and Sahara sand dunes of Utah, and treatments were 1-) control, no treatment applied area left undisturbed 2-) general chemical strip thinning 3-) general chemical thinning of entire stand, 4-) general mechanical strip thinning, and 5-) general mechanical thinning of the entire stand. Significant differences among treatments in seed yields were collected in 2011 at Scipio but not at Sahara. At Scipio, the mechanical strip of competing sagebrush in 3m strips was the most effective of all treatment and produced 2.47kg/ha compared to 4.624kg/ha in the control, but the mechanical land area was only utilizing half the compared control area. The chemical treatments produced 1.819kg/ha and 1.31kg/ha. The percent of sagebrush mortality by each treatment determined the level of competition killed in treatment areas. All treatments at both locations killed at least 57% of the sagebrush. Chemical treatments had a consistent kill rate at both locations, although lower than anticipated, but mechanical kill was the highest at 93% in Scipio. Both mechanical and chemical treated plots had increased cover levels of cheatgrass when compared to the control plots.
48
Saeidi, Ghodratollah. "The effect of seed colour and linolenic acid concentration on germination, seed vigour, seed quality and agronomic characteristics of flax". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ27429.pdf.
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McNamara, Denise. "Endocrine associations with beef carcass quality and yield". Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/5954.
Abstract (sommario):
Thesis (Ph. D.)--University of Missouri-Columbia, 2007.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on March 7, 2008) Includes bibliographical references.
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BOZKIR, EDA. "Genotypic variation of French bean yield and quality". Doctoral thesis, Università Politecnica delle Marche, 2020. http://hdl.handle.net/11566/274908.
Abstract (sommario):
Il fagiolino è il baccello immaturo di molte specie di fagiolo e in particolare del Phaseolus vulgaris, e rappresenta un importante coltura orticola in diversi ordinamenti colturali. Tuttavia, le informazioni su determinanti genetici della qualità del fagiolino, e in particolare del contenuto zuccherino e dell’acidità, non sono disponibili in letteratura scientifica. Scopo della presente tesi è quindi stato studiare le differenze genotipiche in diverse accessioni di fagiolino in termini di contenuto zuccherino, contenuto in acidi e pH. In particolare, sono stati condotti tre esperimenti, in laboratorio, serra e campo, e varie metodologie per l’analisi del contenuto zuccherino sono state esplorate.
L’acido malico è stato sempre trovato in campioni concelati/surgelati. Il contenuto zuccherino è stato molto alto, ma variabile nei campioni freschi e basso e poco variabile in quelli congelati/surgelati. Nella prova in serra, sei genotipi sono stati studiati ed è emerso chiaramente che la dimensione del baccello aveva un forte controllo genotipico a parità di epoca di raccolta, mentre la resa e il numero di baccelli sono variati sia in funzione del genotipo, sia del momento di raccolta. Al contrario della serra, nella prova di campo il peso medio del baccello e il contenuto zuccherino non hanno mostrato differenze tra le tesi, mentre i genotipi hanno mostrato variazioni per il contenuto in acido malico e pH de baccello. Nella systematic map sull’amido resistente del fagiolo, è emerso che i lavori nel settore sono pochi, sebbene sufficienti a delineare alcune caratteristiche relazionate a questo carattere. In particolare, sono stati trovati 1893 studi complessivi relazionati al carattere in esame nelle specie vegetali, dei quali solo 327 riguardavano i legumi. Ad ogni modo, i risultati hanno mostrato che l’amido resistente del fagiolo può conferire al prodotto interessanti caratteristiche nutrizionali e tecnologiche, le quali vanno esplorate adeguatamente.
In conclusione, il controllo genotipico sulla dimensione dei baccelli è apparso molto forte, analogamente al controllo sull’acidità. Questi caratteri, unitamente al contenuto in amido resistente, potrebbero essere presi in considerazione in futuri programmi di breeding.French beans are the fresh pods of Phaseolus vulgaris, which is an important crop both for agriculture, breeding, and nutritional studies. Aim of this research was to evaluate the genotypic differences among various green bean genotypes in terms of Brix, acidity, and pH. Three experiments were performed in the greenhouse and field conditions. In the literature, the protocols related to the sugar analysis in green beans are a few and not always applicable mainly due to the pod structure of green beans (less water, more fiber). Thus, the 1st experiment in the greenhouse was dedicated to find the most suitable method for green bean analysis. The 2nd small-scale greenhouse experiment served to evaluate the genotypic differences, and the yield traits of green beans. In the 3rd experiment, the genotypes were treated with/without the arbuscular mycorrhizal fungi (AMF) and the possible effects of AMF were evaluated. Finally, a systematic mapping of the resistant starch content of legumes, beans and green beans was conducted, to underline the health benefits and technological properties of RS. Fresh green beans contained higher levels of malic acid than frozen ones. Sugar content was high and variable among the genotypes, and more in fresh samples than frozen ones. The results of the 1st greenhouse experiment showed that the yield and number of the pods were changing by the genotype x time interaction. However, the mean pod weight was strongly controlled by the genotype. In the field experiment, AMF didn’t affect the sugar content and pod weight of the genotypes studied. In terms of pH and malic acid content, there were significant differences among the genotypes; the string beans (Striga genotype) had the highest malic acid content and had lower pH than all others. As a conclusion, for all the parameters studied in the greenhouse and field; especially the pod size and acidity seem to be strongly under genotypic control. The other parameters were highly variable among genotypes. The sugar contents are similar, but the acidity and pH levels seemed to shape the taste of green beans. Resistant starch content of green beans can additionally be included in future breeding studies to understand its effect on the taste and yield characteristics.