Dissertations / Theses: 'Seed traits'

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Tangney, Ryan James. "Fire intensity, seasonal variation and seeds traits may influence seed fates in Banksia woodlands." Thesis, Curtin University, 2018. http://hdl.handle.net/20.500.11937/75785.

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This thesis presents a multifaceted approach to understanding seed survival during fire. I considered seed survival of high temperatures in the context of seed moisture content, soil temperature, and seed depth in the soil profile. I identified several seed traits associated with seed survival and seedling emergence depth. I modelled seasonal variation and interactions between these traits, fuel dynamics and soil temperatures to identify conditions and periods for burning that minimise risk of seed mortality.

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Brace, Ryan Christopher. "Agronomic and seed traits of soybean lines with high-oleate concentration." [Ames, Iowa : Iowa State University], 2010. 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:1476279.

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Zhou, Zhou. "NEW SOURCES OF SOYBEAN SEED COMPOSITION TRAITS IDENTIFIED THROUGH FUNCTIONAL GENOMICS." OpenSIUC, 2020. https://opensiuc.lib.siu.edu/dissertations/1786.

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Soybean [Glycine max (L.) Merr.] is the world’s most widely grown protein/oilseed crop and provides about 70% of global protein meal and 53% of vegetable oil in the United States. Soybean seed oil contains five major fatty acids, from which palmitic acid and stearic acid are two saturated fatty acids, oleic acid improves oxidative stability and linolenic acid is an essential fatty acid for human health. Soybean seed protein and oil are two important quality indices for soybean germplasm breeding. Soluble carbohydrates present in soybean meal provide metabolizable energy in livestock feed. To develop soybean germplasm with improved seed composition traits, it is important to discover novel source of seed fatty acid, protein, and carbohydrates traits. This dissertation aims to develop novel functional genomic technology coupled with an integrated approach for facilitating molecular soybean breeding. In this study, the first objective is to develop a high-throughput TILLING (Targeting Induced Local Lesions IN Genomes) by Target Capture Sequencing (TbyTCS) technology to improve the efficiency of discovering mutations in soybean. The robustness of this technology underlies the high yield of true mutations in genes controlling complex traits in soybean. Soybean mutagenized lines with modified fatty acids composition have been successfully developed to meet the different needs of end users. Altered fatty acids phenotypes have been associated with induced mutations in 3-ketoacyl-acyl carrier protein (ACP) synthase II (GmKASII), Delta-9-stearoyl-acyl carrier protein desaturase (GmSACPD), omega-6 fatty acid desaturase 2 (GmFAD2), and omega-3 fatty acid desaturase (GmFAD3) genes identified through TbyTCS. The second objective is to characterize the soybean acyl-ACP thioesterase gene family through a comprehensive analysis. The additional members have been discovered belonging to 16:0-ACP fatty acid thioesterase (GmFATB) gene family. The mutations at oleoyl-ACP fatty acid thioesterase (GmFATA1A) have been revealed to result in the high seed oleic acid content. The novel alleles of GmFATB genes have also been identified to confer low palmitic acid and high oleic acid phenotypes in soybean seeds. The third objective is to assess the phenotypic variations and correlation among seed composition traits in mutagenized soybean populations. Correlation analyses have been conducted among soybean carbohydrates, protein, and oil content of soybean mutagenized populations and germplasm lines. Chemical mutagenesis played an essential role in soybean breeding to generate novel and desired seed composition traits.

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Escamilla, Sanchez Diana Marcela. "Improving Breeding Selection of Seed Quality Traits for Food-Grade Soybeans." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/81963.

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Natto and sprout soybeans are produced using small-seeded soybeans and their production is a high value alternative to grow grain soybeans for food in U.S. The development of soybean cultivars with improved natto and sprout quality is crucial for maintaining and increasing the soyfood market. However, there is insufficient information on sprout soybean characteristics. Therefore, the first objective of this study was to evaluate seed and sprout traits as potential selection criteria and study the storage effect on sprout quality. Seeds can be a vehicle for transmission of pathogens capable of causing human illness. That is why, the second objective was to identify seed-borne pathogens on a commercial soybean cultivar and to evaluate different seed decontamination treatments. Finally, seed coat deficiency is an undesirable trait for natto soybean seeds because it causes inferior appearance of the product. Thus, the third objective was to identify quantitative trait loci (QTL) underlying seed coat deficiency (SCD) and associated markers. Results showed that seed size, high-, average- and low-quality sprout percentage, hypocotyl thickness and length and sprout yield are the most important variables for breeding sprout cultivars; and one-year seed storage at room temperature reduced sprout quality. Fusarium, Alternaria and Diaphorte were the most frequent genera isolated from soybean seeds, and 2% calcium hypochlorite and 5% acetic acid were promising seed disinfection treatments. A stable QTL, qSCD20_1, was identified across two years explaining up to 25% of the variation of SCD; and eight molecular markers tightly linked and nearby qSCD20_1 were identified. Information presented will be helpful for sprout and natto soybean cultivar development.
Master of Science

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Widiarsih, Sasanti [Verfasser], Christian [Akademischer Betreuer] Möllers, Andreas [Gutachter] Börner, and Wolfgang [Gutachter] Link. "Inheritance of seed quality traits, seed germination and seed longevity in three doubled haploid populations of oilseed rape / Sasanti Widiarsih ; Gutachter: Andreas Börner, Wolfgang Link ; Betreuer: Christian Möllers." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2017. http://d-nb.info/1149954612/34.

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Mardorf, Justin Lee. "Agronomic and seed traits of soybean lines with the Rag1 gene for aphid resistance." [Ames, Iowa : Iowa State University], 2010. 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:1476323.

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Atangana, Alain Rene. "Phenotypic diversity in fruit and seed traits, and neutral genetic diversity in Allanblackia Floribunda." Thesis, Université Laval, 2010. http://www.theses.ulaval.ca/2010/27171/27171.pdf.

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Allanblackia floribunda est un arbre des forêts denses humides tropicales valorisé pour la teneur élevée en acides gras de ses graines, essentiellement constitués d’acides stéarique et oléique dont l’efficacité dans la réduction du mauvais cholestérol de l’organisme humain a été prouvée. Pour cette raison, les graines de A. floribunda collectées en milieu naturel sont commercialisées. Toutefois, les travaux sur la culture de cette espèce sont encore à leur phase initiale. Nous avons déterminé la possibilité d’amélioration génétique de cette espèce en échantillonnant 17 à 40 fruits par arbre de 70 arbres distribués sur quatre sites en milieu naturel. La matière grasse a été extraite des graines, et les teneurs en acides stéarique et oléique estimées à l’aide de méthodes développées au cours de cette étude. La variation phénotypique des traits des fruits et des graines a été caractérisée dans et entre les arbres, et entre les sites. Les estimations de répétabilité des caractères mesurés ont été effectuées. Des corrélations phénotypiques entre les traits étudiés ont aussi été estimées, et quatre traits ont été retenus pour effectuer la sélection multi-caractère de 20 arbres-plus qui constitueront la population d’amélioration de cette espèce pour la production des graines. Nous avons par la suite isolé 10 marqueurs moléculaires de type microsatellite polymorphes à partir de A. floribunda, et sept de ces marqueurs étaient polymorphes à la fois chez Allanblackia gabonensis et Allanblackia stanerana. La variation de huit loci microsatellites a permis de caractériser la structure génétique neutre de 10 populations de A. floribunda de zone de forêt naturelle du Cameroun, puis d’inférer l’histoire récente des forêts humides d’Afrique Centrale. Aucune différence significative n’a été observée entre les paramètres génétiques de la population d’amélioration et celle existant en milieu naturel indiquant qu’une amélioration de cette espèce à partir des 20 arbres sélectionnés ne réduirait pas sa diversité génétique neutre. Toutefois, une légère augmentation du taux de consanguinité a été observée dans la population d’amélioration, et des recommandations sont formulées pour la conservation des ressources génétiques durant l’amélioration de A. floribunda.
Allanblackia floribunda or tallow tree is a tropical forest-tree species that is valued for its seeds, which are rich in hard fat consisting mostly of stearic and oleic acids, reported to lower plasma cholesterol levels, thus reducing the risks of heart attack. Owing to this fat profile, Allanblackia oil is used for margarine production and in soap and ointments manufacture, and seeds extracted from Allanblackia fruits by local communities are traded. We determined whether the species could be genetically improved for fruit/seed production by sampling 17 to 40 fruits from each of 70 trees that were distributed among four sites in wild stands. Fat was extracted from the seeds, and stearic and oleic acid content of the fat was estimated using methods developed in this study. Phenotypic variation in fruit/seed traits was assessed within- and among-trees, and among sites. Repeatabilities were estimated for measured characters, and relationships between these characters investigated. Twenty “plus trees” were selected for breeding, and implications for improvement discussed. Then we isolated and characterized ten microsatellite primer pairs for A. floribunda. Seven of these microsatellite loci were polymorph for both Allanblackia gabonensis and Allanblackia stanerana species as well. Using eight informative microsatellite loci, we have characterized the genetic structure of A. floribunda natural populations from Cameroon, and inferred the recent history of rainforests from Central Africa. No significant difference was identified in genetic parameters between wild stands and the breeding population, indicating that breeding A. floribunda from 20 trees would not reduce nuclear genetic diversity. However, a slight increase in inbreeding was observed in the breeding population, and recommendations for genetic diversity conservation during tree improvement in the species are made.

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Rusch, Ursina Denise. "Scatter-hoarding in Acomys subspinosus : the roles of seed traits, seasonality and cache retrieval." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/18076.

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Thesis (MSc)--Stellenbosch University, 2011.
ENGLISH ABSTRACT: With growing concerns about current environmental issues, such as climate change, that affect ecosystems around the world, understanding ecosystem function is becoming increasingly important. In this study, I investigate the plant – seed disperser mutualism between an endemic scatter-hoarding mouse Acomys subspinosus and its Proteaceae plant counterpart Leucadendron sessile in the biodiversity hotspot of the Cape Floristic Region, South Africa. The main objective of this thesis is to investigate the seed selection and caching behaviour of A. subspinosus. First, I determined the seed selection strategy for dispersal and burial by A. subspinosus. Acomys subspinosus may exert stabilizing selection pressure onto L. sessile seeds by dispersing and burying medium seeds with medium hull-thicknesses. Small seeds were eaten in situ and large seeds left at depots. I concluded that the buried L. sessile seeds may have a competitive advantage when it comes to seedling establishment in a post-fire environment, since seeds dispersed by rodents in the fynbos, such as L. sessile, are much larger in size and therefore have more stored nutrients and rapid growth capabilities than seeds dispersed by other vectors. Secondly, I documented rodent dispersal behaviour over a full years’ time. Acomys subspinosus dispersal behaviour changed significantly over the seasons, which I attributed to a change in food availability as the year progressed. Acomys subspinosus buried seeds in autumn after mass seed drop but began to recover caches and consume seeds during winter and spring. The rodent switched to an insectivorous diet in spring. I propose that the A. subspinosus – L. sessile relationship is mutualistic during the year, but the relationship does shift in the favour of the rodent during winter and spring. Lastly, I address the scatter-hoarding behaviour of A. subspinosus and cache recovery ability of its assumed closest food competitor Rhabdomys pumilio. I found that cache size has a profound influence on pilferage rates of L. sessile seeds. Acomys subspinosus scatter-hoarded the majority of seeds singly in the field and R. pumilio had difficulties finding those single-cached seeds in dry substrate under controlled experimental conditions, serving as evidence that scatter-hoarding is an effective method of pilferage mitigation by A. subspinosus during the dry summer months. Relatively little was known about this plant – disperser mutualism and how it functions before this thesis were conducted. I have provided insights into the influence of rodent disperser behaviour on seed morphology development, seed fate and seed persistence in the field and suspect that the plant –disperser relationship may have a larger influence on ecosystem dynamics than previously anticipated. Further research on this system is of importance, especially with today’s emerging environmental instability and human interference that threaten the robustness of highly interconnected ecosystems like the fynbos.
AFRIKAANSE OPSOMMING: Met die huidige omgewingskwessies, soos die klimaatsverandering, wat ekosisteme wêreldwyd affekteer, word die begrip van ekosisteemfunksionering toenemend belangrik. In hierdie studie ondersoek ek die dier – saadverspreidingsmutualisme tussen die endemiese verstrooiings-storing muis Acomys subspinosus en sy Proteaceae plant eweknie Leucadendron sessile in die biodiversiteit 'hotspot’ van die Kaapse Floristiese Ryk, Suid-Afrika. Die hoof doelwit van die tesis is om die saadseleksie en storingsgedrag van A. subspinosus te ondersoek. Eerstens het ek die saadseleksie strategie vir die verspreiding en begrawing deur A. subspinosus bepaal. Acomys subspinosus het direksionele druk uitgeoefen op L. sessile sade deur mediumgrootte sade met medium saadhuiddiktes te versprei en te begrawe. Klein sade was in situ geëet en groot sade was gelaat by afgesette plekke. Ek het die gevolgtrekking gemaak dat die L. sessile sade wat begrawe is ‘n kompeterende voordeel mag hê wanneer dit kom by die vestiging van saailinge in ‘n afgebrande omgewing, aangesien sade wat in die fynbos deur knaagdiere versprei word, soos L. sessile, baie groter is en dus meer gestoorde voedingstowwe en spoedige groeivermoëns het, as sade wat deur ander vektore versprei word. Tweedens het ek die knaagdier verspreidingsgedrag oor die tydperk van ‘n jaar gedokumenteer. Acomys subspinosus se verspreidingsgedrag het beduidend verander deur die verloop van die jaar, wat ek toegeskryf het aan die verandering in voedselbesbikbaarheid soos wat die jaar gevorder het. Acomys subspinosus het sade begrawe in die herfs na grootskaalse vrylating en val van die sade, maar het gestoorde sade begin terug kry en sade begin eet gedurende die winter en lente. Die knaagdier het na ‘n insekvretende dieët omgeskakel in die lente. Ek stel voor dat die A. Supspinosus – L. sessile verhouding nie die hele jaar mutualisties is nie, maar eerder antagonisties, in die knaagdier se guns, gedurende die winter en lente. In die laaste hoofstuk spreek ek die verstrooiings-storingsgedrag van A. subspinosus en storingsverkrygingvermoeë van sy naaste voedselmededinger en deponeringsdief Rhabdomys pumilio aan. Ek het gevind dat die storingsgrootte ‘n beduidende invloed het op die koers van diefstal van L. sessile sade. Acomys subspinosus het die meerderheid van die sade gestoor in die veld en R. pumilio het die enkel-gestoorde sade in droeë substraat onder gekontroleerde eksperimentele kondisies moeiliker gevind. Dit is ondersteunende bewyse dat verstrooings-storingsgedrag ‘n effektiewe metode is om diefstal te verminder in die droë somer in die fynbos. Relatief min was bekend oor hierdie dier – saad verspreidingsmutualisme en hoe dit funksioneer voordat die studie uitgevoer was. Ek het insig verskaf oor die invloed van knaagdier verspreidingsgedrag op saadmorfologie ontwikkeling, die lot van sade en die tydperk wat dit begrawe is in die veld. Ek vermoed dat die mutualisme ‘n hoeksteenproses is in die fynbos en die invloed daarvan op ekosisteemdinamieka mag dalk groter wees as wat voorheen verwag was. Verdere navorsing oor hierdie sisteem is belangrik, veral met vandag se opkomende omgewingsonstabiliteit en menslike inmenging wat die robuustheid van hoogs verbonde-netwerk ekosisteme soos die fynbos bedreig.

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Jablonski, Leanne M. "Reproductive response to elevated CO2 : the roles of vegetative carbon storage, nitrogen and seed traits." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=34646.

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This study focused on the reproductive response to elevated CO2 of plants possessing below-ground storage. I tested the hypotheses that under elevated CO2: (1) Plants with greater non-foliar storage capacity win show more reproductive response and (2) The altered foliar physiology of carbon (C) and nitrogen (N) use will cause increases in seed number and quality. Carbon dioxide treatments of High (650 muL L-1) and Ambient (360 muL L-1) were used in a controlled environment, simulated growing season, and in a natural pasture community. Hypothesis 1 was tested experimentally using four Raphanus varieties that differed in hypocotyl and leaf sizes. N fertilization and harvest times were used to obtain a range of root:shoot ratios. Enhancements in vegetative leaf area rather than the hypocotyl predicted reproductive responsiveness to CO 2. However, after three years of CO2 exposure in the pasture, hypocotyl-storing Taraxacum officinale responded strongly in vegetative biomass which correlated with inflorescence size and number. Fitness was enhanced four-fold, while the leaf-storing Plantago major produced more ramets and had only a two-fold fitness increase. Hypothesis 2 was tested by examining the C and N physiology underlying the vegetative organs and seeds of the pasture plants. Under elevated CO2, photosynthesis increased two-fold and senescence was delayed. Total plant C:N ratio did not differ, suggesting N acquisition increased. N similarly limited seed number in all cases suggesting an unchanged Physiology of N use in reproduction. While morphology constrained total biomass response, provisioning to seeds increased as shown by higher seed mass and number and decreased variability in number and mass. In all cases, leaf mass increase under high CO2 corresponded with fitness increase. Phenology constrained response to CO 2 as there was no plasticity in flowering day in Raphanus and Plantago, while there were flowering delays but greater seed maturation rate in Tar

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Skoneczka, Jeffrey Allen. "Investigation of Putative Genetic Factors Associated with Soybean [Glycine Max (L.) Merr.] Seed Quality Traits." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/40338.

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Soybeans are an economically important plant, with an annual crop value that consistently exceeds 20 billion dollars in the United States alone. A recent increase in demand for soybeans, stemming from its diverse applications in products such as animal feed, oil, and biofuel, has created an emphasis for soybean breeders in value added cultivars. These cultivars, have improved, or altered, agronomic or seed composition traits, allowing them to be efficiently utilized in a specific niche of the processing industry. Facilitating the development of such cultivars requires a thorough understanding of the genetic factors that affect the manifestation of value added traits. Value added traits investigated in this study include seed sucrose, raffinose, stachyose, and phytate content, seed weight, and maturity. The objective of the first part of this project was to characterize the source of low seed stachyose in soybean line PI200508. Two F2 populations, developed from PI200508 and soybean introductions which exhibited higher seed stachyose content were utilized in a QTL analysis approach that incorporated the use of the Williams82 whole genome shotgun (WGS) sequence (http://www.phytozome.org) in a candidate gene mapping approach. A predicted soybean galactosyltransferase gene was established as a candidate gene due to its observed segregation with the single low stachyose QTL observed on molecular linkage group (MLG) C2 in both populations. Sequencing of this putative gene revealed a unique 3 bp deletion in PI200508. A marker developed to exploit this deletion accounted for 88% and 94% of the phenotypic variance for seed stachyose content in the two experimental populations, highlighting its potential for use in marker assisted selection of the PI200508 source of low raffinose and stachyose. The second part of this project involved QTL analysis of seed sucrose, raffinose, stachyose, and phytate content, as well as seed weight in a linkage map for a F8 RIL population developed from the Glycine max line V71-370 and the Glycine soja introduction PI40712. Analysis across all 20 soybean MLG identified 25 QTL for these traits on MLG A1, A2, C2, D1b, D2, F, G, H, I, L, M, O. Nine of these QTL were supported across multiple environments, indicating that they, and their associated markers, could be useful to breeders working with these traits. The third part of this project used the same F8 RIL linkage map to investigate time to maturity (Reproductive stage R8). V71-370 and PI407162 differ in time to maturity when grown in Virginia, and the RILs developed from this cross displayed a wide range in maturity. Two major QTL were identified on MLG H and L. Examination of the Williams82 WGS sequence in these QTL regions revealed two predicted genes with homology to Arabidopsis thaliana light response and photoperiodism genes which were investigated as candidate soybean maturity genes. Markers developed from these predicted genes showed close association with the observed QTL, and could facilitate the further investigation of this complex trait.
Ph. D.

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Mossman, Ronald E. "Seed Dispersal and Reproduction Patterns Among Everglades Plants." FIU Digital Commons, 2009. http://digitalcommons.fiu.edu/etd/135.

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In this study three aspects of sexual reproduction in Everglades plants were examined to more clearly understand seed dispersal and the allocation of resources to sexual reproduction— spatial dispersal process, temporal dispersal of seeds (seedbank), and germination patterns in the dominant species, sawgrass (Cladium jamaicense). Community assembly rules for fruit dispersal were deduced by analysis of functional traits associated with this process. Seedbank ecology was investigated by monitoring emergence of germinants from sawgrass soil samples held under varying water depths to determine the fate of dispersed seeds. Fine-scale study of sawgrass fruits yielded information on contributions to variation in sexually produced propagules in this species, which primarily reproduces vegetatively. It was hypothesized that Everglades plants possess a set of functional traits that enhance diaspore dispersal. To test this, 14 traits were evaluated among 51 species by factor analysis. The factorial plot of this analysis generated groups of related traits, with four suites of traits forming dispersal syndromes. Hydrochory traits were categorized by buoyancy and appendages enhancing buoyancy. Anemochory traits were categorized by diaspore size and appendages enhancing air movement. Epizoochory traits were categorized by diaspore size, buoyancy, and appendages allowing for attachment. Endozoochory traits were categorized by diaspore size, buoyancy, and appendages aiding diaspore presentation. These patterns/trends of functional trait organization also represent dispersal community assembly rules. Seeds dispersed by hydrochory were hypothesized to be caught most often in the edge of the north side of sawgrass patches. Patterns of germination and dispersal mode of all hydrochorous macrophytes with propagules in the seedbank were elucidated by germination analysis from 90 soil samples collected from 10 sawgrass patches. Mean site seed density was 486 seeds/m2 from 13 species. Most seeds collected at the north side of patches and significantly in the outer one meter of the patch edge (p = 0.013). Sawgrass seed germination was hypothesized to vary by site, among individual plants, and within different locations of a plant’s infructescence. An analysis of sawgrass fruits with nested ANOVAs found that collection site and interaction of site x individual plant significantly affect germination ability, seed viability, and fruit size (p < 0.050). Fruit location within a plant’s infructescence did not significantly affect germination. As for allocation of resources to sexual reproduction, only 17.9% of sawgrass seeds germinated and only 4.8% of ungerminated seeds with fleshy endosperm were presumed viable, but dormant. Collectively, only 22% of all sawgrass seeds produced were viable.

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Jablonski, Leanne M. "Reproductive response to elevated CO¦2, the roles of vegetative carbon storage, nitrogen and seed traits." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0008/NQ36986.pdf.

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AL-Amery, Maythem. "IMPACT OF A HIGH OIL AND PROTEIN ON AGRONOMIC TRAITS AND OVERALL SEED COMPOSITION IN SOYBEAN." UKnowledge, 2017. https://uknowledge.uky.edu/pss_etds/97.

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New soybean lines have been developed with significantly higher oil, protein + oil and higher meal protein. These soybeans contain a VgD1 gene (highly active acyl-CoA:diacylglycerol acyltransferase, DGAT from Vernonia galamensis (VgDGAT1A) produces much higher oil synthesis and accumulation activity in soybean. Soybean with active DGAT from Vernonia galamensis (VgDGAT1A) has active TAG biosynthesis relative to other DGATs including from soybeans and Arabidopsis. DGATs catalyze the final step of TAG synthesis: DAG (diacylglycerol) + acyl-CoA → TAG + CoASH (Coenzyme A is notable for its role in the synthesis and oxidation of fatty acids, and the oxidation of pyruvate in the citric acid cycle). A thorough analysis of the major components in VgD1 lines, especially those of nutritional or anti-nutritional value including what else changed (decreased); and what remained at normal levels was conducted. A field study was conducted in Spindletop and Princeton KY, reviled no reduction in yield nor protein, and about 4 % (DW) more oil was obtained in Princeton and 2% (DW) in Spindeltop. No consistent reduction in the other seed composition.VgDGAT1A soybean lines indicated noticeably early maturation compared to the parental line. This is associated with higher expression of the flowering genes FT2 (FLOWERING LOCUS T2) and FT5 (FLOWERING LOCUS T5), for the high oil lines. A single recessive mutation in soybean (MIPS) myo-inositol 1-phosphate synthase, confers a seed phenotype of increase inorganic phosphate (Pi) crossed with high oil lines expressing a DGAT from Vernonia galamensis (VgDGAT1A) (VgD). The oil and protein were maintained compart to VgD. VgD X MIPS (VM), had 21.2, and 22 % oil in 2015, and 23.3 and 24.0 oil in 2016, and protein 46, 49 in 2015, and 37 and 39 % in 2016. Phosphate results suggesting the cross MV is still segregating for MIPS and more selection and planting are needed. Measurement of seed phosphate levels is an established technique for screening for low phytate mutants but to date, it has not been performed non-destructively from single soybean seeds. A protocol was developed greatly reducing the sample size thereby reducing the cost and time and saving a generation in the selection of low phytate mutant seeds based on the high Pi phenotype. Genotyping single seeds are useful in breeding and genetics while maintaining high germination rates. Nondestructive single-seed genomic DNA extraction protocols using 12 mg cotyledon tissue with a modified cetyl trimethyl ammonium bromide (CTAB) technique and a commercial seed DNA extraction kit using 1 mg cotyledon tissue were developed for dry soybean seeds and cross-verified with leaf DNA analysis.

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Marteinsdóttir, Bryndís. "Plant community assembly in grazed grasslands." Doctoral thesis, Stockholms universitet, Institutionen för ekologi, miljö och botanik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-102185.

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Species assembly into local communities from the surrounding region can be caused either by species failure to reach the site (i.e. seed limitation) or to establish (i.e. establishment limitation). The aim of this thesis was to investigate plant species assembly and to determine the relative importance of different factors in that process. In a cultivated landscape in southeast Sweden, plant community assembly was studied in grazed ex-arable fields. Community assembly from the surrounding region into the local community was explored using trait-based null models and seed sowing and transplanting experiments. The influence of local environmental factors and landscape history and structure on community assembly was also studied. In addition, differences in species assembly between ex-arable fields and semi-natural grasslands were explored. Seed limitation was the strongest filter on local community assembly. Only a fraction (36%) of species in a region dispersed to a local site and adding seeds/transplants increased species establishment. Species abundance at the regional scale, species dispersal method and seed mass strongly influenced which species arrived at the local sites. Establishment limitation also affected the assembly. Of species arriving at a site 78% did establish, seedling survival was low and which species established was influenced by species interactions, local environmental conditions and stochastic events. In addition, landscape structure that determined the species richness in the regional species pool influenced the local assembly. The comparison between assembly in ex-arable fields and semi-natural grasslands indicated that the main cause of difference in species assembly between them was difference in their age. The main conclusion of this thesis is that regional processes are more important than local factors in determining plant community assembly.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Submitted. Paper 4: Submitted. Paper 5: Manuscript.

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Lu, Jiaqi. "The effect of sexual selection and mating on personality traits and behavior consistency of Callosobruchus maculatus." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-392202.

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Animals’ personality traits are defined as consistent behavior tendencies and the function of them in life-history strategy and reproductive success has been given a lot of explanations in a large amount of research. However, the behavior consistency of individuals in different sexes, mating status and selection regimes is rarely mentioned. In this research, we were interested in personality traits and their consistency in inter-individuals and intra-individuals, and proposed that with the removal of fecundity selection males would evolve to be more female-like and decrease their locomotor activity, and copulation would change the physiological status of females and thus alter their levels of activity. In the experiment, seed beetles (Callosobruchus maculatus) that were artificially selected in monogamy, polygamy and male-limited selection regimes were weighed, dropped in a designed arena and their behaviors were recorded with a camera for four minutes in the first day when they were newborn and virgin. In the next day, the virgin beetles were randomly paired to mate, weighed afterwards, and dropped in the arena again for videoing the same setting as yesterday. In data collection step, with these videos four behaviors types including walking, entering squares, time spent on roof and entering a new area were observed, scored and noted down. To process the data, we made correlation analysis and it was found that walking, entering square and a new area were positively correlated. After building the linear mixed effect models we found that sex together with mating significantly act in modifying beetles’ behaviors, males were more active than females but the difference was narrowed after mating, and copulation caused a significant increase in the level of locomotor activity in females. To our disappointment, selection regimes did not have any significant impact on locomotor activity. Our work gave an insight that copulation changed individuals’ behaviors more in females than in males and dimorphic expression of sex-biased genes differed due to mating effect.

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Wills, Timothy Jarrod 1974. "Succession in sand heathland at Loch Sport, Victoria : changes in vegetation, soil seed banks and species traits." Monash University, Dept. of Biological Sciences, 2002. http://arrow.monash.edu.au/hdl/1959.1/7742.

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Guja, Lydia. "The influence of morphological and physiological seed traits on oceanic dispersal and germination in saline coastal environments." Thesis, Curtin University, 2014. http://hdl.handle.net/20.500.11937/59664.

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This thesis investigates the morphological and physiological seed traits that influence the capacity of coastal plant seeds to be dispersed by the ocean and germinate in post-dispersal environments. A series of multidisciplinary experiments that examine the ecology, biology and physiology of coastal seeds are presented. The high buoyancy and broad germination thresholds of the tested species indicate that they have a capacity for oceanic dispersal.

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Kiran, Aysha [Verfasser]. "Genetic and phenotypic analysis of complex seed and root traits in oilseed rape (Brassica napus L.) / Aysha Kiran." Gießen : Universitätsbibliothek, 2015. http://d-nb.info/1068874821/34.

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Maughan, Peter Jeffrey. "Microsatellite polymorphism, orthologous evolution and molecular marker analysis of seed quality traits in soybean (Glycine max L. Merr.)." Diss., This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06062008-163918/.

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Seger, Guilherme Dubal dos Santos. "Efeitos filogenéticos em atributos reprodutivos de espécies endozoocóricas em uma floresta com Araucaria no sul do Brasil." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/27518.

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Os processos de dispersão, sobrevivência da prole e os períodos fenológicos das espécies vegetais, são o resultado tanto de sua história evolutiva quanto de suas adaptações ao ambiente. Para analisar o padrão evolutivo destes processos, foi testada a hipótese de que a similaridade entre espécies aparentadas em relação aos seus atributos reprodutivos (frutos, sementes e a fenologia da floração e frutificação) é maior do que o esperado por mero acaso (alto sinal filogenético), através de testes de Mantel parcial controlando o efeito da forma de vida das espécies. Os resultados revelaram que a maioria dos atributos de sementes, dois atributos dos diásporos (display das cores e a porcentagem de polpa) e o tempo de desenvolvimento dos diásporos, apresentaram um moderado sinal filogenético. Isto sugere que a conservação de atributos de sementes para sobrevivência da prole e a labilidade dos atributos de diásporos buscando dispersões mais efetivas, afetam significativamente o fitness das espécies, além de indicar uma influência do tempo de desenvolvimento dos diásporos nos picos de frutificação.
The processes of dispersal, offspring survival and phenological periods of plant species result both from their evolutionary history and adaptations to the environment. To analyze the evolutionary pattern of these processes, the hypothesis that the similarity among related species in relation to their reproductive traits (fruits, seeds and the phenology of flowering and fruiting) is higher than expected by chance (high phylogenetic signal) was tested through partial Mantel tests, controlling for the effect of species life form. The results revealed that most seed traits, two diaspores traits (color display and pulp percentage) and the time of diaspore development, show moderate phylogenetic signal. This suggests that the conservation of seed traits for offspring survival and the lability of diaspore traits seeking more effective dispersions, significantly affect the species fitness, and it also indicates the influence of the time of diaspore development on the fruiting peaks.

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Casas, Grasiela. "Padrões de diversidade de aves e rede de interação mutualística ave-planta em mosaico floresta-campo." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/141942.

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Estudos clássicos com diversidade taxonômica, apesar de serem essenciais, não consideram as diferenças funcionais entre as espécies de uma comunidade. A abordagem considerando atributos funcionais e diversidade funcional vem preenchendo esta lacuna. A compreensão da estrutura e dinâmica de interações mutualísticas também é um elemento essencial em estudos de biodiversidade, permitindo a investigação de mecanismos ecológicos e evolutivos. Porém, a maioria dos estudos com redes de interação disponíveis na bibliografia são pequenas em número de espécies e interações, e é possível que estes dados não tenham sido suficientemente amostrados. Além disto, estudos têm mostrado que muitas métricas utilizadas em análises de rede de interação são sensíveis ao esforço amostral e ao tamanho da rede. Os objetivos desta tese foram: 1) investigar a diversidade taxonômica (DT) e funcional (DF) de aves e os padrões de organização de espécies de aves em comunidades refletindo convergência de atributos (TCAP: Trait Convergence Assembly Patterns) ao longo de transições entre floresta e campo; 2) analisar a estrutura de redes de dispersão de sementes de plantas por aves, utilizando as métricas de rede aninhamento, modularidade, conectância e distribuição do grau; 3) desenvolver um método estatístico visando avaliar suficiência amostral para métricas de redes de interação usando o método bootstrap de reamostragem com reposição. A composição de espécies de aves diferiu entre os ambientes, indicando uma substituição de espécies ao longo da transição floresta-borda-campo. DT diferiu significativamente somente entre floresta e borda de floresta, enquanto que ambas diferiram significativamente do campo em relação à DF. DT e DF podem indicar diferentes processos de organização de comunidades ao longo de mosaicos floresta-campo. A correlação significativa entre TCAP e o gradiente floresta-campo indica que provavelmente mecanismos de nicho atuam na organização da comunidade de aves, associados a mudanças na estrutura do habitat ao longo da transição floresta-borda-campo agindo como filtros ecológicos. Redes de dispersão de sementes de plantas por aves aparentemente apresentam um processo comum de organização, independentemente das diferenças na intensidade de amostragem e continentes onde as 19 redes utilizadas foram amostradas. Usando reamostragem bootstrap, encontramos que suficiência amostral pode ser alcançada com diferentes tamanhos amostrais (número de eventos de interação) para o mesmo conjunto de dados, dependendo da métrica de rede utilizada.
Classic studies on taxonomic diversity, though essential, do not consider the functional differences between species in a community. Studies using functional traits and functional diversity are filling this gap. Understanding the structure and dynamics of mutualistic interactions is also essential for biodiversity studies and allows the investigation of ecological and evolutionary mechanisms. However, most networks published are small in the number of species and interactions, and they are likely to be under-sampled. In addition, studies have demonstrated that many network metrics are sensitive to both sampling effort and network size. The aims of this thesis were: 1) to investigate bird taxonomic diversity (TD), functional diversity (FD), and patterns of trait convergence (TCAP: Trait Convergence Assembly Patterns) across forest-grassland transitions; 2) to analyse the structure of seed-dispersal networks between plants and birds using the metrics of nestedness, modularity, connectance and degree distribution; 3) to develop a statistical framework to assess sampling sufficiency for some of the most widely used metrics in network ecology, based on methods of bootstrap resampling. Bird species composition indicated species turnover between forest, forest edge and grassland. Regarding TD, only forest and edges differed. FD was significantly different between grassland and forest, and between grassland and edges. TD and FD responded differently to environmental change from forest to grassland, since they may capture different processes of community assembly along such transitions. Trait-convergence assembly patterns indicated niche mechanisms underlying assembly of bird communities, linked to changes in habitat structure across forest-edge-grassland transitions acting as ecological filters. Seed dispersal mutualistic networks apparently show a common assembly process regardless differences in sampling methodology or continents where the 19 networks were sampled. Using bootstrap resampling we found that sampling sufficiency can be reached at different sample sizes (number of interaction events) for the same dataset, depending on the metric of interest.

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Liu, Yang. "Eco-evolutionary perspective on life-history traits with special emphasis on seed dormancy and its genetic basis of adaptation in conifers." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/59232.

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Life-history traits, known as fitness components, are related to the timing and success of development, reproduction, and senescence throughout the life cycle. Selection in variable environments may favor plants to defer germination until suitable conditions occur. Seed dormancy is an innate constraint on germination timing and prevents germination during periods that are ephemerally favorable. The timing of seed germination is the earliest life-history trait that is expressed and sets the context for the traits that follow. As such, seed dormancy may be construed as an adaptation for survival during bad seasons and can exert cascading selective pressures on subsequent life stages. Seed size is another important life-history trait linking the ecology of reproduction and seedling establishment with that of vegetative growth. As the two traits are, at modulations, regulated by hormone signaling cascades, evolve under correlated selective pressures, and exhibit co-varying phenotypes, this dissertation intended to elucidate their eco-evolutionary dynamics and possible genetic basis of adaptation. From an eco-evolutionary perspective, I demonstrated that dynamic climatic variables rather than constant geographic variables are the true environmental driving forces in seed dormancy and size variations in Pinus contorta Dougl. Evapotranspiration and precipitation in the plant-to-seed transition are the most critical climatic variables for seed dormancy and size variations, respectively. Unlike random temperature fluctuations between generations, wide temperature shifts considerably alter population structures and accelerate life-history evolution. Regarding the genetic basis of adaptation, environmental cues trigger different seed-set programming in Picea glauca and Arabidopsis by employing lineage-specific and deeply conserved microRNAs at different expression levels, respectively, to entrain phenotypical variations, such as dormancy intensities. Our findings additionally point to auxin as a key player that likely works in conjunction with the ABA and GA signal pathways previously investigated in mechanisms underpinning the seed-to-plant transition by chilling in Picea glauca seeds. This dissertation increases our understanding of plant evolution and persistence in the context of climate change and provides fundamental insight for understanding how microRNAs are at play in seed-set programs to regulate phenotypes, how winter chilling contributes to the timing of phenology, and how conifer life histories may develop under new climate scenarios.
Forestry, Faculty of
Graduate

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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.

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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

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24

Revenikioti, Maria. "Life history and reproductive fitness variation associated with the Y chromosome in Callosobruchus maculatus." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-435099.

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In the seed beetle Callosobruchus maculatus, the female is the larger sex and the male is the smaller sex. However, males that are almost as large as females can also occur, which is due to a specific Y chromosome haplotype. This Y chromosome polymorphism is not expected since the Y chromosome does not recombine and has lost genetic variation as a consequence. Nevertheless, the Y chromosome manages to maintain this polymorphism. Thus, the questions asked are how this occurs and how the large male Y haplotype persists to exist since previous studies have shown how small males have the higher fitness. In this study, large males were from line SL3b Y and small males were from line SL1b Y. To answer the questions, two important measures of fitness were conducted, mating- and lifetime reproductive success, as well as lifetime-history traits of the SL1b Y and SL3b Y males. Males from line SL3b Y turned out to have a faster growth rate and a shorter development time compared to the SL1b Y males. Both the SL3b Y males with a shorter development time and the SL1b Y males with a longer development time had larger body sizes. Large males also showed to have heavier ejaculate weight and produced more offspring compared to the other male Y haplotype. However, neither of the males had higher pre-mating success. In conclusion, the two male Y haplotypes must coexist in nature since their traits are beneficial in different environments and circumstances.

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Lindgren, Åsa. "Effects of herbivory on arctic and alpine vegetation." Doctoral thesis, Stockholm University, Department of Botany, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-6746.

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The distribution of plant species and functional traits in alpine and arctic environments are determined by abiotic conditions, but also by biotic interactions. In this thesis, I investigate interactions among plants and herbivory effects on plant community composition and plant functional traits in three different regions: Swedish Lapland, Beringia (USA/Russia) and Finnmark (Norway). Reindeer grazing was found to be extensive in southern Lapland and had limited effects on plant community composition and seedling germination. However, reindeer presence was found to influence plant functional traits, particularly in the subalpine birch forest. Tall herbs were lower and had lower SLA when reindeer were present, while small herbs showed an opposite pattern. The contrasting effects on the two herb groups are probably explained by a competitive release for small herbs when the tall herbs are suppressed by reindeer. Rodents had the largest relative impact on plant community composition in southern Lapland and this is consistent with the study from Finnmark, where rodents heavily affected dwarf shrubs on predator-free islands. With no predators present, vole densities increased profoundly and almost depleted some dwarf shrub species. These results support the idea that small mammals in arctic and alpine tundra are controlled by predators (i.e. top-down). However, a decrease in the nutritional quality in a sedge after defoliation gives support for the idea that small mammals are regulated by plant quality (i.e. bottom-up). In Beringia, small and large herbivores differed in the relation to plant community composition, since large herbivores were related to species richness and small herbivores were related to plant abundance. Plant functional traits were related only to large herbivores and standing crop of vascular plants.

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26

Глинянська, Анастасія Едуардівна. "Вивчення біологічних властивостей льону у процесі позакласної роботи учнів." Магістерська робота, ЗНУ, 2020. https://dspace.znu.edu.ua/jspui/handle/12345/3437.

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Глинянська А. Е. Вивчення біологічних властивостей льону у процесі позакласної роботи учнів : кваліфікаційна робота магістра спеціальності 014 "Середня освіта" / наук. керівник І. О. Полякова. Запоріжжя : ЗНУ, 2020. 76 с.
EN : This paper presents 76 pages of printed text, contains 8 tables, 13 figures. References includes 69 sources. The object of the study was selected annual wild species of the genus Linum: Linum angustifolium, Linum bienne, Linum crepitans, Linum hispanicum. The work has relevance in our time in the practice of wild species of flax in genetic and breeding work and to create new valuable source material by interspecific hybridization. The aim was to study the variability of economically valuable signs four-year wild species of flax for further practical use of these species. To solve this problem used the following research methods: field, phenological observations, biometric measurements, laboratory techniques and statistical analysis method. The practical value of species of the genus Linum is due to the presence of their representatives of beneficial properties; аmong flax there are textile, oil, honey, medicinal, fodder, eyeliner, decorative and other plants. Flax cultivation can be grown in all soil-climatic zones of Ukraine due to biological properties and environmental adaptation. The main regions of cultural flax cultivation are the southern regions (Zaporozhye, Dnipropetrovsk, Mykolaiv, Kherson), although in recent years the area under this culture has increased in the regions of the central and northern regions. The rapid development of breeding culture creates a wide range of species of wild flax research. In particular, scientists are interested in wild flax features that can be used in further breeding work to create a more productive sorts improved. The study involved flax culture long ago, but the involvement of wild species of the source material is a trend of recent research. Therefore, the study features signs in wild flax that can be used to improve the culture of flax is a hot topic. Further research of wild species of flax opens new opportunities for expanding breeding work in the direction of creating a source material with increased resistance to biotic and abiotic environmental factors. The novelty lies in the collection, preservation and study of the genetic diversity of the genus Linum. The study of wild species for further involvement in breeding programs is a very promising area of work. Significance of work.
UA : Дана робота викладена на 76 сторінок друкованого тексту, містить 8 таблиць, 13 рисунків. Список літератури включає 69 джерел. Об’єктом дослідження було обрано однорічні дикорослі види роду Linum: Linum angustifolium, Linum bienne, Linum crepitans, Linum hispanicum. Робота має актуальність у наш час в практиці застосування диких видів льону в генетико-селекційній роботі та для створення нового цінного вихідного матеріалу методом міжвидової гібридизації. Метою роботи було дослідження мінливості господарсько-цінних ознак чотирьох однорічних диких видів льону для подальшого практичного використання цих видів. Для вирішення поставлених задач застосовували наступні методи досліджень: польовий, фенологічні спостереження, біометричні вимірювання, лабораторні методи та метод статистичної обробки. Швидкий розвиток селекції культури створює широкий спектр дослідження дикорослих видів льону. Зокрема, науковців цікавлять особливості диких видів льону, які можна використовувати в подальший селекційній роботі для створення більш продуктивних покращених сортiв. Дослідженням культури льону займаються дуже давно, але залучення дикорослих видів як вихідного матеріалу є тенденцією останніх досліджень. Тому вивчення особливостей ознак диких видів льону, які можна використати для покращення культурного льону є актуальною темою. Новизна полягає в зборі, збереженні та вивченні генетичного різноманіття видів роду Linum. Вивчення диких видів для подальшого залучення у селекційні програми є дуже перспективним напрямком роботи.

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27

Berry, Christopher J. J. "Post-dispersal seed predation in a conifer-broadleaf forest remnant : the importance of exotic mammals." Lincoln University, 2006. http://hdl.handle.net/10182/666.

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Despite extensive international acceptance of the critical role of mammalian post-dispersal seed predation in many plant communities, in New Zealand we have limited knowledge of these predators’ influence on plant recruitment in our forests. The principle objective of my thesis was to determine the importance of exotic mammals as post-dispersal seed predators in a New Zealand conifer-broadleaf forest remnant. To address this goal, I used a series of field-based experiments where the actions of different post-dispersal seed predators were separated by wire-mesh exclosures. My study was conducted at Mount Peel Forest Park Scenic Reserve, South Canterbury, New Zealand. Being a human modified conifer forest currently dominated by broadleaf species, it is typical of forest remnants in New Zealand. This presented an opportunity to study a wide range of both potential post-dispersal seed predators and broadleaf tree species. My findings indicate that exotic mammals are not only post-dispersal seed predators at Peel Forest, but are responsible for the majority of post-dispersal predation events observed. Ship rats (Rattus rattus) were the dominant post-dispersal seed predators, while brushtail possums (Trichosurus vulpecula), house mice (Mus musculus) and native invertebrates were also important post-dispersal seed predators for several tree species. Through use of time-lapse video and cafeteria experiments I found that exotic mammalian seed predators, when compared to native invertebrate seed predators, preyed upon larger-seeded plant species and were responsible for considerable seed losses of several tree species. However, exotic mammalian seed predators do share several foraging characteristics with native invertebrate seed predators, as predators foraged in similar habitats and responded in a similar way to changes in seed density. In investigating if post-dispersal seed predation by mammals had a flow-on effect to plant recruitment, I observed natural seedling densities at Peel Forest were significantly higher in the absence of mammalian seed predators, but I found no evidence that the presence of mammals significantly altered the overall species richness. At the community level, I did not find an interaction between habitat and exotic mammals, however I present evidence that for individual plant species a significant mammal : habitat interaction occurred. Consequently, even though my cafeteria experiment implied there was no significant difference in the overall amount of seed preyed upon within different habitats, the less favourable microsite conditions for germination under an intact continuous canopy allows mammals to exacerbate habitat-related patterns of seed mortality and have a noticeable effect on seedling establishment. In an effort to validate the use of manipulative experiments to predict the long-term effect of post-dispersal seed predation on plant dynamics, I attempted to link results of my cafeteria experiment with observed seedling abundance at Peel Forest. Seven tree species were used in this comparison and a strong correlation was observed. This result shows that the level of post-dispersal seed predation determined in the cafeteria experiment provided a good predictor of the effect of mammalian post-dispersal seed predation on seedling establishment. To fully gauge the impact of mammalian post-dispersal seed predators on seedling establishment, the relationship between these seed predators and the type of recruitment limitation experienced by a plant species was also investigated. By using a combination of seed addition, plot manipulations and seed predator exclusion I was able to investigate this relationship. I found evidence that seed limitation at Peel Forest is positively correlated with seed size, and that while mammalian post-dispersal seed predators can further reduce plant recruitment of plant species experiencing seed limitation, the influence of mammals in determining plant recruitment was limited for plant species experiencing microsite limitation. My study has proven that exotic mammals are now the dominant post-dispersal seed predators at Peel Forest, the amount of seed preyed upon varies among plant species, and post-dispersal seed predation by mammalian species can lead to differences in seedling richness and abundance. I proved that the influence of exotic mammals on seedling establishment is also linked to habitat structure and recruitment limitations. When combined these observations suggest that exotic mammalian post-dispersal seed predators may play an important role in determining landscape abundance and distribution of plants at Peel Forest.

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Arène, Fabien. "Ecologie comparative de la germination : des plantes à graines au genre Silene en région PACA." Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4339.

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La germination est un processus clé qui conditionne la régénération des plantes dans leur milieu ainsi que leur distribution. Connaître les conditions thermique et hydrique qui permettent aux plantes de germer est un préalable nécessaire à l’identification des menaces qui pèsent sur elles et tout particulièrement dans un contexte de changement climatique. Les modèles en temps thermique et temps hydrique permettent de prédire la phénologie de germination sur le terrain en fonction des conditions climatiques dans l’environnement de la graine dépassant des valeurs seuil de température et de potentiel hydrique de base, Tb et Ψb (i.e. respectivement la température minimale et le potentiel hydrique minimum permettant la germination).Dans ce travail de thèse, il est donc question d’étudier l’écophysiologie de la germination à l’aide de ces modèles à deux échelles taxonomiques : (i) celle des plantes à graines et (ii) à l’échelle du genre Silene de la région PACA. Dans les deux cas le but est d’évaluer les contraintes évolutives des traits de réponse au climat de la germination ainsi que leurs liens avec les contraintes morphologiques et phénologiques des plantesLes résultats de cette thèse montrent un fort signal phylogénétique des traits de germination de la température de base et une plus grande labilité pour le potentiel hydrique de base quelle que soit l’échelle taxonomique considérée. En revanche, les liens avec les traits des plantes, tels que la masse des graines, sont plus variables et dépendent à la fois de l’origine biogéographique et de la longévité des espèces
Germination is a key process in plant reproduction, a critical and irreversible phase conditioning the regeneration and distribution of plants. Understanding how temperature and water act on germination, is major step prior to identify risks plants may undergo under warming climate. Thermal time and hydrotime modelling of germination are useful tools to predict germination in the field as a function of climatic conditions above threshold value of temperature and water potential (respectively base temperature, Tb, and base water potential, Ψb) in a seed’s environment. This PhD thesis aimed at studying germination ecophysiology at two contrasted taxonomic scales: (i) for all seed plants and (ii) at the restricted level of the genus Silene in the Provence Alpes Côte d’Azur region. In both cases the objective was to evaluate evolutionary implications of the germination traits, Tb and Ψb and their link with plant morphological and phenological constraints. This work is structured in three parts : (I) Temperature but not moisture response of germination shows phylogenetic contraints while both interact with seed mass and life span ; (II) Germination ecophysiology in the Silene genus : thermal time and hydrotime models ; (III) Comparative ecology of Silene germination : relation with plant traits and climate.The mains results of this work show strong evidences of phylogenetic signal in base temperature and greater lability for base water potential at both taxonomic scales. The links with plant traits such as seed mass depend on biogeographical origins and life span

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Pereira, Elise de Matos [UNESP]. "Estratégias de seleção e efeito de armazenamento de sementes em populações segregantes de soja." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/141481.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O presente estudo foi realizado com os objetivos principais de: verificar as associações existentes entre caracteres agronômicos e caracteres relacionados à qualidade fisiológica de sementes de soja; determinar alterações fisiológicas e no teor de óleo em sementes de soja, ao longo do período de armazenamento, além de selecionar progênies superiores de soja por meio de análises multivariadas. Para isto, as relações existentes entre os caracteres agronômicos de plantas e fisiológicos de sementes foram verificadas por meio da análise de correlações canônicas em sete populações e duas cultivares comerciais, em três gerações: plantas F3 e sementes F4; plantas F4 e sementes F5; e sementes e plantas na geração F4. Os caracteres agronômicos de plantas (grupo I) avaliados foram: número de dias para maturidade, altura da planta na maturidade, altura de inserção da primeira vagem, número de vagens, produção de grãos e teor de óleo. A qualidade fisiológica das sementes (grupo II), foi avaliada por meio do teste de germinação, envelhecimento acelerado, emergência e índice de velocidade de emergência. As mesmas populações e cultivares também foram avaliadas antes do armazenamento e após seis meses, armazenadas em ambiente com temperatura e umidade controladas, através de testes de germinação, vigor, teor de água e teor de óleo, em esquema fatorial 2 x 9. Para as análises multivariadas, 20 populações segregantes de geração F4, foram avaliadas para os seguintes caracteres agronômicos: número de dias para florescimento, número de dias para maturidade, altura da planta na maturidade, altura da inserção da primeira vagem, número de ramos, número de vagens, número de nós, produção de grãos e teor de óleo. Utilizou-se a técnica de componentes principais e análise de agrupamento pelo método não hierárquico de k-médias, além dos índices de seleção Mulamba e Mock e Smith e Hazel. Observou-se que os caracteres agronômicos de plantas e fisiológicos de sementes não são independentes. As associações intergrupos para a geração de plantas F3 e sementes F4 foram estabelecidas por plantas com maior número de vagens, mais produtivas e com alto teor de óleo, as quais estão associadas com sementes de alta germinação e velocidade de emergência. Na geração de plantas F4 e sementes F5, há associação entre ciclo de maturidade reduzido, sementes de alta porcentagem de emergência e alta porcentagem de plântulas normais após o envelhecimento acelerado. Pelo segundo par canônico plantas mais produtivas e de porte alto estão associadas com maior vigor de sementes de soja. Para a geração de sementes e plantas F4 as associações estabelecidas foram sementes de alto vigor estão associadas a plantas mais produtivas, com alto teor de óleo e ciclo de maturidade reduzido. E pelo segundo par canônico há associação entre sementes de alta qualidade fisiológica e plantas de porte alto. O armazenamento das sementes por seis meses em ambiente controlado afetou a qualidade fisiológica e o teor de óleo das sementes, sendo que os genótipos de soja apresentam diferentes níveis de tolerância ao armazenamento e teores de óleo. A análise de componentes principais resultou em 3 componentes principais (CP1, CP2 e CP3), os quais explicam 65,82% da variância total contida nas nove variáveis. Os caracteres de maior contribuição na discriminação dos genótipos em CP1 foram produção de grãos, número de ramos, número de vagens, número de nós e número de dias para maturidade. As progênies selecionadas 36, 37, 38, 39, 40, 41, 65, 75, 80, 89 e 95 apresentam bom potencial produtivo. As análises de k-médias formaram nove grupos, o grupo superior foi formado pelas progênies 36, 38, 39, 40, 65, 75, 79 e 80. Dentre as 18 progênies selecionadas pelos índices de seleção, 10 foram concordantes com os componentes principais. As análises multivariadas permitiram a seleção de progênies superiores para os caracteres relacionados à produção de grãos e teor de óleo.
This study aimed to examine the associations between agronomic traits and traits related to physiological seed quality in soybean seeds, determine physiological and oil content alterations during the storage and select superior progenies using multivariate analysis. For this, the relationships between agronomic traits and physiological of seed traits were evaluated using canonical correlation analysis in seven segregating populations and two commercial cultivars conducted in three generations: plants F3 and seeds F4, plants F4 and seeds F5 and seeds and plants in generation F4. The agronomic traits (group I) evaluated were: number of days to maturity, plant height at maturity, first pod height, number of pod per plant, grain yield and oil content. The seed physiological quality (group II) was evaluated by percentage of germination, percentage of emergence, emergence speed index and accelerated aging. The same populations and cultivars were also evaluated before the storage and after six months stored in cold room by germination test, vigor, seed moisture and oil content, arranged in a 2 x 9 factorial design. For the multivariate analysis, 20 segregating populations in generation F4 were evaluated using the following agronomic traits: number of days to flowering, number of days to maturity, plant height at maturity, first pod height, number of branches per plant, number of pod per plant, number of nodes per plant, grain yield and oil content. It was used the principal components technique and the non-hierarchical clustering method of k-means and also the rank summation index Mulamba and Mock and classical selection index Smith and Hazel. The analysis of canonical correlation showed that the groups are not independent. Inter-group associations, in the generation of plants F3 and seeds F4, were establish by plants with more pods, higher grain yield and oil content are associated with seeds with high germination and emergence speed index. For the generation plants F4 and seeds F5, there are associations between short-season plants, seeds with high emergence and percentage of germination under conditions of accelerated aging. In the second canonical pair, higher-yielding and taller plants are associated with high vigor soybean seeds. For the generation seeds and plants F4 the associations established were, seeds with high vigor are associated with short-season and higher-yielding plants and high oil content. And in the second canonical pair there is association between seeds with high physiological quality and tall plants. The storage for six months in cold room affected the physiological quality and the oil content of the seeds and the soybean genotypes shown different levels of tolerance of storage and different oil content. The principal components analysis resulted on 3 principal components (PC1, PC2 and PC3), which explained 65,82% of the total variance in nine variables. The traits with higher contribution to discriminate the progenies in PC1 were grain yield, number of branches, number of pods, number of nodes and number of days to maturity. The selected progenies 36, 37, 38, 39, 40, 41, 65, 75, 80, 89 and 95 shown good productive potencial. The clustering analysis, k-means allowed the formation of nine groups, the superior group contains the progenies 36, 38, 39, 40, 65, 75, 79 and 80. Among the 18 progenies selected by the selection indexes, 10 were consistent with principal components analysis. The multivariate analysis allowed selecting superior progenies for the evaluated characters, especially for the components related to grain production and oil content.

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Zirondi, Heloiza Lourenço. "O efeito do histórico do fogo na fenologia reprodutiva e atributos de sementes e germinação em espécies de Cerrado /." Rio Claro, 2019. http://hdl.handle.net/11449/182467.

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Orientador: Alessandra Fidelis
Resumo: No Cerrado, um dos fatores abióticos que influenciam na fenologia das plantas é o fogo, o qual é um distúrbio natural que interfere em diversos ecossistemas do mundo. O fogo altera as condições do habitat podendo afetar a floração, frutificação, atributos das sementes e germinação. Portanto, esse projeto visou compreender o efeito do fogo na fenologia reprodutiva e nos atributos de semente e germinação da comunidade do Cerrado. Para isso, foram realizadas a contagem do número de ramos (vegetativos e reprodutivos) por espécie, realizados em 30 subparcelas de 1x1m em áreas com diferentes históricos de fogo (C=6 anos sem queima e FB=recentemente queimada). Também foram marcados indivíduos de diferentes espécies dominantes em ambas as áreas. A comunidade e os indivíduos tiveram sua floração acompanhados a cada 15 dias durante 3 meses após a queima e então aos 6, 9 e 12 meses. Os seguintes atributos das sementes e germinação foram medidos: forma e peso da semente, teor de água, germinabilidade, tempo médio de germinação e sincronia. Nossos resultados mostraram que o fogo aumentou a floração nas áreas queimadas. Já nos primeiros 30 dias até 3 meses após a queima houve até 2 vezes mais espécies que floresceram nas áreas FB comparados a C. Também houve um aumento significativo na proporção de ramos reprodutivos aos 3 meses pós-fogo na comunidade, mostrando que a profusão reprodutiva ocorre nos primeiros meses após queima. Dentre as espe... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: In Cerrado one of the abiotic factors that influences plant phenology is fire, which is a natural disturbance that interferes with several ecosystems in the world. Fire changes the conditions of the habitat and can affect flowering, fruiting and seeds and germination traits. Therefore, this project aimed to understand the effect of fire on reproductive phenology and on seed and germination traits of Cerrado community. For this purpose, the counting of the number of branches (vegetative and reproductive) by species was carried out in 30 subplots of 1x1m in areas with different fire histories (C = 6 years without burning and FB = recently burned). We also marked individuals of different dominant species in both areas. The community and individuals had their flowering counted every 15 days for 3 months after burning and then at 6, 9 and 12 months. The following seed and germination traits were measured: seed shape and mass/weight, water content, germinability, mean germination time and synchrony. Our results showed that fire increased flowering in burned areas. Already after 30 days up to 3 months after the burning there were up to 2-fold more species flowering in the FB areas compared to C. There was also a significant increase in the proportion of reproductive shoots at 3 months post-fire in the community, showing that the reproductive profusion occurs in the first few months after burning. Among the species of the community 66.39% can be considered stimulated by fire. Seed an... (Complete abstract click electronic access below)
Mestre

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Shukla, Ushma. "Dispersion épizoochore des graines par les ongulés sauvages dans des paysages changeants : le cerf élaphe comme étude de cas." Thesis, Orléans, 2020. http://www.theses.fr/2020ORLE3060.

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L'épizoochorie définit la dispersion des plantes véhiculées sur le corps des animaux. Elle concerne herbacées et graminées, arbres et arbustes étant dispersés par endozoochorie et vecteurs abiotiques. Filtre biotique sélectif, elle façonne les communautés végétales locales à partir du pool régional d'espèces. Les populations abondantes d’ongulés sauvages et leurs longs déplacements créent ainsi de fréquents "liens mobiles" entre patchs d'habitat. J’ai ainsi étudié le rôle de ces animaux, notamment du cerf élaphe, comme vecteurs de dispersion épizoochore dans la structuration des communautés végétales locales en tenant compte des traits des plantes favorisant la dispersion. Puis, j’ai évalué comment structure et composition du paysage affectaient les déplacements individuels du cerf, les distances de dispersion et le site de dépôt des graines. Finalement, j’ai comparé différents modes de dispersion à l’échelle du vecteur individuel. Pour répondre à ces questions, j'ai combiné données empiriques de terrain et approches de modélisation écologique. J'ai constaté que la zoochorie constitue un signal faible, par rapport aux facteurs abiotiques, dans la structuration des communautés végétales, mais les traits facilitant la dispersion sont de bons prédicteurs. J'ai montré l'importance de tenir compte du domaine vital individuel pour ne pas surestimer les distances de dispersion. En outre, j'ai démontré qu’il fallait considérer la charge totale en graines véhiculées car elle révèle la complémentarité des modes de dispersion. Pour finir, j'alerte sur le rôle sous-estimé des ongulés sauvages et domestiques dans la propagation des plantes exotiques, réelle menace pour la biodiversité
Epizoochory is one mode of plant dispersal, where seeds are conveyed externally on animals. It mostly concerns forbs and graminoids, shrubs and trees relying more on endozoochory or abiotic vectors. Epizoochory is considered a strong biotic filter that shapes local plant assemblages from the regional pool of species. Abundant populations of large-bodied ungulates and their home range movements provide frequent ‘mobile links’ among habitat patches. For my thesis, I was interested in assessing the role of wild ungulates, especially red deer, in epizoochorous seed dispersal. I addressed 1) the role of ungulates in structuring local plant communities with respect to dispersal-related plant traits, 2) the effect of landscape composition on movement decisions made by individual red deer on subsequent seed dispersal kernels, and 3) the complementarity of ungulate-mediated dispersal modes and their overall influence on local plant communities. I used a combination of empirical field data and ecological modeling to address these questions. I found that zoochory presents a weak signal in structuring plant communities compared to other abiotic factors, but that dispersal-enabling traits were good predictors. I demonstrated the importance of accounting for home ranging behavior in range-resident ungulates in the seed dispersal kernel, which prevents from over-estimating dispersal distances. Moreover, I underlined how considering the total seed load dispersed by individual red deer is crucial and reveals the complementarity of dispersal modes in the total dispersal kernel. Finally, I highlighted the underrated role of ungulates in spreading invasives as a real threat to biodiversity

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Boigné, Audrey. "Restauration écologique de prairies humides à vocation agricole suite au comblement d'une ballastière en basse vallée de Seine : incidence du type de sol recréé sur les fonctions pédologiques associées et sur la dynamique de colonisation végétale." Thesis, Normandie, 2017. http://www.theses.fr/2017NORMR008/document.

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Dans un contexte de destruction des zones humides à l’échelle mondiale, conséquence des activités d’origine anthropique, la restauration écologique de ces milieux et de leurs fonctions est devenue un enjeu écologique et sociétal. L’objectif de ce projet est de recréer des prairies humides à vocation agricole aux caractéristiques pédologiques et floristiques aussi proches que possible de celles des prairies totalement détruites par l’exploitation de matériaux alluvionnaires. L’étude présentée ici se focalise sur l’incidence des matériaux pédologiques utilisés pour la recréation de quatre sols sur les fonctions du sol et les cortèges floristiques associés. L’hypothèse principale est que la recréation d’un sol morphologiquement proche de celui détruit devrait permettre d’orienter la restauration écologique.L’hypothèse sous-jacente est qu’en utilisant différents matériaux pédologiques locaux, on hérite de leurs caractéristiques physico-chimiques et biologiques ce qui permettait de conserver les fonctions pédologiques qui leur sont associées et favorisait le retour d’un cortège floristique compatible avec un usage agricole. La première partie est consacrée à l’étude de deux fonctions remplies par les sols de zones humides à savoir le stockage du carbone organique et la dénitrification. Deux années et demi après la fin des travaux de comblement de ballastières, ces deux fonctions sont conservées au sein des quatre types de sols recréés. Les principaux résultats montrent un niveau d’efficience des matériaux pédologiques testés, fonction de leur sol origine et de leurs caractéristiques physico-chimiques. La deuxième partie est consacrée à l’étude des mécanismes de structuration des communautés végétales. Le suivi de la colonisation spontanée de la végétation a permis d’appréhender la forte contribution de la banque de graines issue des matériaux pédologiques locaux. Malgré la mise en évidence d’un début de trajectoires dynamiques au sein des quatre sols recréés, la similarité entre les communautés obtenues et les communautés cibles des prairies de référence n’excède pas 50 %. Les productions de biomasses aériennes associées à ces communautés sont comparables en quantité à celles des prairies de référence mais pas en qualité. La mise en place d’une gestion par semis associée à une fauche montre dès la première année une production de biomasses de qualité se rapprochant de celles des prairies locales.La dernière partie de ce manuscrit est consacrée à l’effet de trois niveaux d’engorgement des sols sur le processus de dénitrification et sur les traits de réponse d’une espèce prairiale, Holcus lanatus. Placer les quatre matériaux pédologiques dans des conditions identiques d’engorgement permet de souligner l’importance de l’héritage des communautés bactériennes dénitrifiantes sur le processus de dénitrification. Parallèlement, ces conditions expérimentales permettent de mettre en évidence les traits de réponses morphologiques et fonctionnels de l’espèce considérée. À l’issue de ces suivis, le meilleur compromis de restauration alliant sol, végétation et coûts économiques doit prendre en considération l’origine et l’histoire (i.e. gestion) des matériaux utilisés lors de la recréation écologique
In a worldwide context of wetland destruction, a consequence of anthropic activities, ecological restoration of such habitats and their functions has become a societal and ecological issue. The objective of this project is to recreate agriculture-oriented wet grasslands with pedological and floristical properties as similar as possible to typical grasslands destroyed by alluvial materials extraction. The study presented here focuses on the impact of pedological materials, used in the re-creation of four soils, on soil functions and associated floristic processions. The main hypothesis is that re-creation of a soil morphologically similar to the previously destroyed one should drive ecological restoration. The underlying hypothesis is that different local pedological materials inherit their previous physicochemical and biological properties. This should conserve associated pedological functions and favor the return of a floristic procession compatible with agricultural exploitation. The first part is dedicated to the study of carbon storage and denitrification, two wetlands soils functions. These two functions are retained within the four re-created soils two and a half year after gravel-pit filling. Main results highlight functional efficiency levels of tested pedological material inherited from their respective initial topsoil physico-chemical properties. The second part is devoted to the study of mechanisms structuring plant communities. The high contribution of local pedological materials seed bank during the colonization process and its impact on aforementioned mechanisms was highlighted from our monitoring. Despite demonstration of the start of a dynamic trajectory in the four created soils similarity between obtained and target communities never exceeds 50%. Aerial biomass production associated to these communities is comparable to the production in reference wet grasslands in terms of quantity, but not quality. Implementation of management (sowing and mowing) shows biomass production of comparable quality to reference grassland from the first year onwards. The last part focuses on the effect of three soil waterlogging levels on the denitrification process and the response traits of Holcus lanatus, a meadow species. Pedological materials placement in identical waterlogging conditions highlights the importance of denitrifying bacteria communities inheritance on the denitrification process. These experimental conditions also enabled us to highlight the considered species morphological and functional response traits. To conclude and following our monitoring the best compromise for concurrent restoration of soil and vegetation while considering cost-effectiveness needs to account for topsoils origin and history (i.e. management)

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Braun, Joanne. "Box Turtles, Terrapene carolina, as Potential Seed Dispersers: Effects of Passage Through Digestive Tracts on Seed Germination." W&M ScholarWorks, 1985. https://scholarworks.wm.edu/etd/1539625298.

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Hallsson, Lára R. "Quantitative Trait Evolution in a Changing Environment in a Seed Beetle." Doctoral thesis, Uppsala universitet, Zooekologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-159284.

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During the last decades the climate has been changing more rapidly than in the preceding periods. This is for instance characterized by an increase in temperature. Interestingly, such changes in the environment are not necessarily constant over time as they often show high levels of fluctuation. Organisms are exposed to these changes and respond to them and a recent theoretical model predicts that fluctuations in the environment are important for populations’ response to climate change. The aim of this thesis is to investigate how populations respond to a changing environment, including fluctuations. My thesis is based on the previously mentioned theoretical model and I used a suite of laboratory experiments on the seed beetle Callsosobruchus maculatus, to test the model predictions in a quantitative genetic framework. First, I assessed the genetic architecture of several life history and morphological traits in order to verify that there is sufficient additive genetic variation for the population to respond to changes in the environment. Second, I tested the detailed model predictions explicitly, by investigating whether different types of environmental fluctuations matter for a population’s response. Third, I investigated changes in quantitative genetic variation after i) a rapid shift in temperature and ii) long term selection under increasing temperature including fluctuations. Fourth, I concentrated on sex differences in response to temperature, and finally, I assessed the relative importance of genetic and nongenetic inheritance for traits that differ in their plastic response to a change in the environment. I found that environmental fluctuations are highly important for a population’s response to environmental change. I could detect changes in a set of quantitative genetic parameters, suggesting that a population’s potential to respond to selection, environmental sensitivity and the evolution of phenotypic plasticity are affected by the selective past. I also found that sexes differ in additive genetic variation and plasticity and that parental effects may play an important role in the evolutionary process. Therefore, future studies would benefit greatly from considering details of the selective past and especially environmental fluctuations during attempts to predict how populations respond to a changing environment, particularly with regards to climate change.

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Buru, Joshua Comrade. "Comparative biology of two forms of an invasive vine, Dolichandra unguis-cati (L.) Lohmann (Bignoniaceae): implications for weed spread and biocontrol." Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/102084/1/Joshua%20Comrade_Buru_Thesis.pdf.

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This thesis is a comparative study of two distinct forms ('long pod' and 'short pod') of an invasive vine, cat’s claw creeper. The two forms have differing prevalence rates in Australia. The thesis examines important plant traits that could explain this variation in prevalence between the forms. The thesis covers seed biology, anatomical and growth traits, together with physiological traits in response to two levels of light, water and nutrients resources. In addition, the study assesses preferences of two bio-agents (insects) against the two forms of cat’s claw creeper to ascertain bio-control efficacy. This is because in Australia, the same insects are used to control both forms. The outcome of the study is a prospectus of traits that help explain why the short pod form is more widespread than the long pod form. Short pod possesses many of the traits that are associated with fast growing plants that easily colonize habitats. Generally, insects feed and lay eggs on both forms.

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Freewalt, Keith. "Creation of a High Density Soybean Linkage Map, QTL Mapping and the Effects of Marker Number, Population Size and Significance Threshold on Characterization of Quantitative Trait Loci." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1402656287.

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Bonnardeaux, Yumiko Graciela. "Seed dormancy in barley (Hordeum vulgare L.) : comparative genomics, quantitative trait loci analysis and molecular genetics." University of Western Australia. Faculty of Natural and Agricultural Sciences, 2008. http://theses.library.uwa.edu.au/adt-WU2009.0019.

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[Truncated abstract] Under prolonged wet and damp conditions, barley grain with low dormancy can germinate precociously, a condition known as preharvest sprouting that causes a number of detrimental effects in grain quality. In particular, preharvest sprouting renders the grain unsuitable for malting. The aim of this study was to take a genomics approach to identify and characterise candidate genes that could be linked to the control of seed dormancy in barley. This thesis developed a bioinformatic strategy that exploited the availability of gene sequences with functional evidence in the model species of Arabidopsis and rice. The bioinformatic strategy integrated phenotypic data (QTL data) and comparative genomics for a targeted approach in identifying candidate genes with a high probability of having a conserved function in cereals. This bioinformatic study identified two candidate genes ERA1 and ABI2 with strong evidence for a role in seed dormancy based on their function in Arabidopsis in abscisic acid (ABA) signal transduction and their co-location to seed dormancy QTLs in Arabidopsis, rice and wheat. In order to establish whether the candidate genes mapped to seed dormancy QTLs in barley, QTL analyses were performed on a double haploid population, not previously studied, developed from a cross between Stirling, a major Australian malting cultivar, and Harrington, a major Canadian malting cultivar. This cross was specifically chosen for this study, as elucidation of chromosomal regions associated with seed dormancy in the background of a malting cultivar would make a significant contribution for the malting industry. '...' Identification of a seed dormancy QTL on the long arm of 3H, in a region syntenic to the wheat chromosome locations of ESTS aligning to the ERA1 and ABI2 genes, laid the foundation for physical and genetic mapping of the candidate genes to investigate whether the genes co-located to the QTL on 3H. Physical mapping of the genes in wheat barley addition lines confirmed their positions on the long arm of 3H. Genetic mapping of the ERA1 gene was performed using a CAPS marker developed in this thesis. The genetic mapping of the ERA1 gene did not place the gene within either of the minor QTLs on 3HL, although segregation distortion may have influenced the map position of this gene. Further investigation is required to resolve the positioning of the ERA1 and ABI2 genes in relation to the 3H seed dormancy QTL. The main outcomes of this study have been 1) identification of candidate genes for further study; 2) identification of QTLs on the long arm of 3H that were previously unknown; 3) demonstration of the potential differences in dormancy that can be achieved through the use of specific gene combinations, highlighting the importance of minor genes and the epistatic interactions that occur between them and; 4) the development of a CAPS marker for the ERA1 gene, which can be used to track the gene in barley breeding programs to observe its association with important agronomic traits. This thesis also pioneered the implementation of several new technologies including multiplex-ready PCR (Hayden et al. 2008) for fluorescencebased SSR genotyping and QTLNetwork (Yang et al. 2008) for statistical analysis of QTLs. Seed dormancy is a complex trait and is likely to involve the interplay of a number of genes that have a role in other developmental and regulatory processes.

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Yesudas, Charles R. "Seed and leaf trait correlations and identification of underlying loci in soybean (Glycine max (L.) Merr.) /." Available to subscribers only, 2008. http://proquest.umi.com/pqdweb?did=1559850551&sid=1&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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Pereira, Elise de Matos. "Estratégias de seleção e efeito de armazenamento de sementes em populações segregantes de soja /." Jaboticabal, 2016. http://hdl.handle.net/11449/141481.

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Orientador: Sandra Helena Unêda-Trevisoli
Coorientador: Antonio Orlando Di Mauro
Coorientador: Cibele Chalita Martins
Banca: Everton Luis Finoto
Banca: Ivana Marino Bárbaro Torneli
Banca: Rinaldo Cesar de Paula
Banca: Gustavo Vitti Môro
Resumo: O presente estudo foi realizado com os objetivos principais de: verificar as associações existentes entre caracteres agronômicos e caracteres relacionados à qualidade fisiológica de sementes de soja; determinar alterações fisiológicas e no teor de óleo em sementes de soja, ao longo do período de armazenamento, além de selecionar progênies superiores de soja por meio de análises multivariadas. Para isto, as relações existentes entre os caracteres agronômicos de plantas e fisiológicos de sementes foram verificadas por meio da análise de correlações canônicas em sete populações e duas cultivares comerciais, em três gerações: plantas F3 e sementes F4; plantas F4 e sementes F5; e sementes e plantas na geração F4. Os caracteres agronômicos de plantas (grupo I) avaliados foram: número de dias para maturidade, altura da planta na maturidade, altura de inserção da primeira vagem, número de vagens, produção de grãos e teor de óleo. A qualidade fisiológica das sementes (grupo II), foi avaliada por meio do teste de germinação, envelhecimento acelerado, emergência e índice de velocidade de emergência. As mesmas populações e cultivares também foram avaliadas antes do armazenamento e após seis meses, armazenadas em ambiente com temperatura e umidade controladas, através de testes de germinação, vigor, teor de água e teor de óleo, em esquema fatorial 2 x 9. Para as análises multivariadas, 20 populações segregantes de geração F4, foram avaliadas para os seguintes caracteres agronômicos: númer... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: This study aimed to examine the associations between agronomic traits and traits related to physiological seed quality in soybean seeds, determine physiological and oil content alterations during the storage and select superior progenies using multivariate analysis. For this, the relationships between agronomic traits and physiological of seed traits were evaluated using canonical correlation analysis in seven segregating populations and two commercial cultivars conducted in three generations: plants F3 and seeds F4, plants F4 and seeds F5 and seeds and plants in generation F4. The agronomic traits (group I) evaluated were: number of days to maturity, plant height at maturity, first pod height, number of pod per plant, grain yield and oil content. The seed physiological quality (group II) was evaluated by percentage of germination, percentage of emergence, emergence speed index and accelerated aging. The same populations and cultivars were also evaluated before the storage and after six months stored in cold room by germination test, vigor, seed moisture and oil content, arranged in a 2 x 9 factorial design. For the multivariate analysis, 20 segregating populations in generation F4 were evaluated using the following agronomic traits: number of days to flowering, number of days to maturity, plant height at maturity, first pod height, number of branches per plant, number of pod per plant, number of nodes per plant, grain yield and oil content. It was used the principal compone... (Complete abstract click electronic access below)
Doutor

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Liu, Jun. "Quantitative Trait Loci Controlling Sclerotinia Stem Rot Resistance and Seed Glucosinolate Content of Oilseed Rape (Brassica napus L.)." Australian Journal of Plant Science, 2016. http://hdl.handle.net/1993/31662.

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Canola/rapeseed (Brassica napus L.) is a major oilseed crop worldwide. However, its production is largely affected by the fungal disease Sclerotinia stem rot as well as seed glucosinolates. So far the genetic mechanisms controlling these two traits have been poorly understood. In the present study, three bi-parental doubled haploid B. napus populations M730, M692 and ZT were grown in either natural or artificial environments and genotyped using the Brassica 60K Infinium® SNPs and/or sequence related amplified polymorphisms. Three genetic linkage maps covered 2,597.7 cM, 2,474.1 cM and 1,731.6 cM in 19 chromosomes for M730, M692 and ZT, respectively. Plants were inoculated with Sclerotinia sclerotiorum mycelia on stems at the reproductive stage to evaluate their resistivity. Four aliphatic glucosinolates and one indolic glucosinolate were detected in the seeds using high-performance liquid chromatography. 4-hydroxy-3-indolylmethyl predominated over aliphatic glucosinolates in canola, but inversely constituted a small portion of total glucosinolate content in semi-winter rapeseed. In rapeseed, 2-hydroxy-3-butenyl predominated in 4C aliphatic glucosinolates, which in turn predominated in total aliphatic glucosinolates, which likewise predominated in total glucosinolate content. QTLs regulating major glucosinolates were located on chromosome A9 for high glucosinolate content populations M730 and ZT, and on chromosome C7 for low glucosinolate content population M692. Major QTLs for Sclerotinia stem rot resistance were located on chromosomes A7 and C6 in M730, on chromosomes A3 and A7 in ZT, while no major QTLs were found in M692. Additive genetic effect was the major factor explaining phenotypic variations of the two traits. No direct genetic relationship was observed between Sclerotinia stem rot resistance in adult plants and seed glucosinolates in B. napus. The findings in the studies could be used to formulate breeding and research strategies in B. napus and the major QTLs controlling the two traits and their closely linked SNP markers could be validated over wide germplasm and used in marker assisted selection.
October 2016

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Bayer, Skylar (Skylar Rae). "Reproductive traits of pioneer gastropod species colonizing deep-see hydrothermal vents after an eruption." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/65300.

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Thesis (S.M.)--Joint Program in Biological Oceanography (Massachusetts Institute of Technology, Dept. of Biology; and the Woods Hole Oceanographic Institution), 2011.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 27-33).
The colonization dynamics and life histories of pioneer species are vital components in understanding the early succession of nascent hydrothermal vents. The reproductive ecology of pioneer species at deep-sea hydrothermal vents may provide insight into their dispersal, population connectivity, and ability to colonize after disturbance. An opportunity to study the reproductive traits of two pioneer gastropod species, Ctenopelta porfera and Lepetodrilus tevnianus, presented itself in 2006 after an eruption on the East Pacific Rise (EPR) eliminated vent communities near 9°50'N. Standard histological techniques were used to determine whether reproductive characteristics, such as timing of gamete release, fecundity, or time to maturation, differed from other vent gastropods in ways that might explain arrival of these two species as early colonizers. Both species exhibited two-component oocyte size frequency distributions that indicated they were quasi-continuous reproducers with high fecundity. In C. porifera, the oocyte size distributions differed slightly between two collection dates, suggesting that environmental cues may introduce some variability in gamete release. In samples collected within one year of the estimated eruption date, individuals in populations of both C. porfera and L. tevnianus were reproductively mature. The smallest reproducing C. porifera were 4.2 mm (males) and 5.4 mm (females) in shell length, whereas reproductive L. tevnianus were smaller (2.3 and 2.4 mm in males and females respectively). Most Cporifera in the population were large (> 6.0 mm) compared to their settlement size and reproductively mature. In contrast, most L tevnianus were small (< 1.0 mm) and immature. Reproductive traits of the two species are consistent with opportunistic colonization, but are also similar to those of other Lepetodrilus species and peltospirids at vents, and do not explain why these particular two species were the dominant pioneers. It is likely that their larvae were in high supply immediately after the eruption due to oceanographic transport processes from remote source populations.
by Skylar Bayer.
S.M.

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Afsarigolshan, Maryam. "Source strength verification and quality assurance of sterile, pre-loaded iodine-125 seed trains used for prostate brachytehrapy." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/46404.

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Jaramillo, Paul E. "Farmers' valuation and adoption of new genetically modified corn seeds nitrogen-fertilizer saving and drought tolerance traits /." [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0024899.

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Cicek, Mine II. "Genetic Analysis of Quantitative Trait Loci Associated with Seed Sucrose Content Using Molecular Markers in an Interspecific Glycine Cross." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36506.

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Sucrose content is one of the important seed quality traits in soybean, especially for oriental soyfood production. However, little genetic information is available on this quantitative trait yet. A previous study was conducted on seed sucrose content of soybean using a population of F2-derived lines from an interspecific cross between an adapted high-sucrose (8.3%) G. max breeding line (V71-370) and a low sucrose (1.6%) G. soja plant introduction (PI407162). Nineteen marker loci, mapping to seven linkage groups (A1, A2, E, F, L1, I, and M), were significantly associated with seed sucrose content after screening 178 polymorphic genetic markers, including RFLPs, SSRs, RAPDs and morphological markers. The replicated field experiments were planted in 1993 and 1995. The objective of my study was to evaluate QTLs associated with seed sucrose content utilizing an additional 153 F2:3 families from the same cross. DNA samples from the additional families were analyzed with the nineteen genetic markers associated with sucrose in the previous study. Sucrose data were obtained from seeds harvested from a field experiment conducted in 1995. Single factor analysis of variance results for the sucrose data obtained from the 153 F2:3 families were compared to the 1995 data for the 144 F2:3 families of the previous study. Of the nineteen genetic markers significantly associated with seed sucrose content in the previous study, seven were also significantly associated in this study. These genetic markers include sgA458a on linkage group A2, NBS61 on linkage group E, sgB164, R-B4a and sgB162 on linkage group L1, and R-B4b and sgA144 on linkage group I. The percent phenotypic variation explained by significant individual markers varied from 2.9 to 6.8% in the 153 F2:3 families. This study shows that seed sucrose content, a quantitative trait, may be improved using the molecular marker technology. Further research is necessary in different genetic backgrounds of G. max in order to implement these markers in a breeding program for selection.
Master of Science

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Scott, Kelsey L. "Studies in the Management of Pythium Seed and Root Rot of Soybean: Efficacy of Fungicide Seed Treatments, Screening Germplasm for Resistance, and Comparison of Quantitative Disease Resistance Loci to Three Species of Pythium and Phytophthora sojae." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1524147394255409.

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Cardinal-McTeague, Warren Martin. "The Systematics and Evolution of Euphorbiaceae Tribe Plukenetieae." Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/38206.

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The aim of this dissertation is to study the systematics and evolution of Euphorbiaceae vines (tribe Plukenetieae), a diverse pantropical lineage (~365 species and 18 genera) composed of three morphologically distinct subtribes, Dalechampiinae, Plukenetiinae, and Tragiinae. Through the course of my research I largely resolved the evolutionary history of Plukenetieae and made broader contributions to the study of pollen and seed evolution, pantropical biogeography, and plant diversification. In chapter two I developed the first well-sampled molecular phylogeny for Plukenetieae (154 terminals, ~93 species, 2,207 character dataset composed of ITS and psbA-trnH with indel gap-scored data), and determined baseline species group relationships of the tribe. Molecular phylogeny largely agreed with pollen morphology hypotheses and confirmed that the large genus Tragia was para- and/or polyphyletic and should be split into smaller genera. Analysis of pollen morphology revealed a trend towards aperture reduction and loss in Tragiinae, with four origins of weakly defined apertures and up to three origins of inaperturate pollen. In chapter three, I studied the seed size evolution of Plukenetia, a pantropical genus with large edible oil-rich seeds, by developing a near-exhaustive phylogeny (83 terminals, 20 of ~24 species, 5,069 bp dataset of ETS, ITS, KEA1 introns 11 and 17, TEB exon 17, matK, ndhF) and conducting ancestral state estimation and phylogenetic regression. Seed size evolution in Plukenetia was dynamic and associated with competing selective pressures of plant size, fruit type (and inferred dispersal syndrome), and seedling ecology. In chapter four I presented a revised sectional classification of Plukenetia based on phylogeny and morphological evidence, including three new taxa from South America. Chapters three and five included biogeographical investigations on Plukenetia and Plukenetieae. Analyses revealed that pantropical disjunct distributions arose one to three times in each subtribe via periodic long-distance dispersals from the Oligocene to the Pliocene, most often from South America to Africa and then Southeast Asia. Lastly, in chapter five, I developed an improved phylogeny for Plukenetieae (289 terminals, ~109 species, 5,160 bp dataset of ETS, ITS, KEA1 intron 11, TEB exon 17, matK, ndhF) to study the influence of innovative traits (twining growth form, stinging hair defences, and pseudanthial inflorescences) on diversification in the tribe. However, increased diversification was not associated with innovative traits. Instead, diversification was associated with clades that shifted into drier open habitats, aided by habitat expansion following the Late Miocene cooling period.

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Morgan, Megan Jayne. "Identification of molecular-genetic determinants of quality traits of tomato fruit." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:662d8b1e-70cf-44fb-9ed3-46dcacc39bad.

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Tomato is an important food crop and a model for fleshy fruit development. The process of fruit ripening involves changes in chemical composition and in particular the accumulation of sugars, organic, amino acids and carotenes. The research described in this thesis aimed to identify key regulatory aspects associated with the accumulation of the major acids in tomato fruit by analysis of introgression lines resulting from a cross between a cultivated variety, Solanum lycopersicum, and a wild progenitor species, Solanum pennellii. Line 2-5 showed increases in citrate, malate, aspartate and glutamate in fruit grown under greenhouse conditions. The genetic differences between line 2-5, its overlapping lines, sub-introgression lines and the recurrent parent were used to link the metabolite phenotypes to smaller chromosomal regions. This analysis suggested multiple epistatic loci control fruit metabolite accumulation. Investigation of the biochemical differences between line 2-5 and the recurrent parent revealed that organic and amino acid accumulation did not dependent upon increased TCA cycle capacity. Regulation at the metabolic level was identified for citrate accumulation with changes in cytosolic aconitase in line 2-5. As these metabolites accumulate in the vacuole, tonoplast transport was investigated. Correlation of ATPase-dependent malate influx with altered malate content suggested malate tonoplast transport plays a role in malate accumulation and highlights the importance of vacuolar storage and transport in the regulation of organic and amino acid accumulation.

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Shaw, Sarah. "Traces of empire, seeds of desire : Africa and women in the novels of Naomi Mitchison." Thesis, University of Essex, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395948.

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Javed, Nasir. "Development of Genetic Linkage Maps and Identification of Quantitative Trait Loci Influencing Seed Oil Content, Fatty Acid Profile and Flowering Time in Brassica napus L." Hereditary Genetics, 2012. http://hdl.handle.net/1993/30633.

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Identification of allelic variation through quantitative trait loci (QTL) mapping offers possibilities for the improvement of quantitatively inherited traits. This requires a genetic map along with the phenotypic characterization of a mapping population. A doubled haploid (DH) Polo X Topas population consisting of 194 lines and a recombinant inbred line population of 92 lines was developed. Individual genetic maps derived from each population were integrated into a consensus map. The DH-based genetic map was used for QTL mapping. The DH-based map was comprised of 620 loci that were assembled into 19 linkage groups that were anchored to the B. napus chromosomes. The DH-based map covered 2244.1 cM genomic distance with an average marker interval of 3.7 cM. The DH population was phenotyped in four environments with each line replicated twice in a randomized complete block design. Days to flowering was recorded and oil content and fatty acid composition were determined using Near Infrared spectroscopy (NIR) and Gas Chromatography, respectively. Fourteen QTL were identified for oil content, 33 QTL for palmitic acid content, 18 QTL for stearic acid content, 21 QTL for oleic acid content, 20 QTL for linoleic acid content, 23 QTL for linolenic acid content, 16 QTL for arachidic acid content and 14 QTL for flowering time. Oil content QTL were identified on five linkage groups, A3, A10, C1, C5, and C6. An oil content QTL, qOIL-A10c appeared in all four environments, whereas qOIL-A10a appeared in only one environment but explained 26.99% variation. The oil content in the population ranged from 35% to 55.5% with the parents having values of 42% to 46%. Two genomic regions on C3, with map positions at 147.83 cM and 154.55 cM harbored QTL (rQTL) for all the fatty acids studied. The additive effects of the rQTL reveal a correlation pattern which is supported by the phenotypic correlation observed between the fatty acids. This suggests rQTL have role in the fatty acid composition and possibly determine total seed oil content. The rQTL and flanking markers of the identified QTL offer utility in further development of B. napus.
October 2015

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Bonneau, Lynda. "School experiences of foster children as seen through the eyes of teachers : a project based upon an independent investigation /." View online, 2008. http://hdl.handle.net/10090/8378.

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Dissertations / Theses on the topic 'Seed traits'

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