Master of Science / Department of Agronomy / Ignacio Ciampitti / Soybean [Glycine max (L.) Merr.] yields have continuously increased over time. Seed yields are determined by the genotype, environment, and management practices (G × E × M) interaction. Closing yield gaps require a continuous improvement in the use of the available resources, which must be attained via implementation of better management decisions. Linear relationships between seed yield and nitrogen (N) demand are reported in the scientific literature. Main sources of N to the plant are the biological N fixation (BNF) and the soil mineralization processes. On overall, only 50-60% of soybean N demand is met by the BNF process. An unanswered scientific knowledge is still related to the ability of the BNF to satisfy soybean N demand at varying yield levels. Seed N demand not met by N fixation plus soil mineral N, is then fulfilled by the remobilization of N from vegetative organs during the seed filling period. An early remobilization process reduces the photosynthetic activity (leaves) and can limit seed yield. The objectives of this project were to: i) study yield improvements and contribution of N via utilization of contrasting N conditions under historical and modern soybean genotypes, and ii) quantify main seed N sources during the seed filling period. For objective one, four field experiments were conducted during the 2016 and 2017 growing seasons in Kansas, United States (US) and Santa Fe Province, Argentina (ARG). Those experiments investigated twenty-one historical and modern soybean genotypes with release decades from 1980s to 2010s. As for objective two, three field experiments were conducted during the 2015 and 2016 growing seasons in Kansas, US, studying three soybean genotypes: non-roundup ready (RR), released in 1997; RR-1, released in 2009; and RR-2, released in 2014. Across all studies, seeds were inoculated and tested under three N management strategies: i) control without N application (Zero-N); ii) 56 kg N ha-1 applied at reproductive growth stages (Late-N); and iii) 670 kg ha-1 equally split at three timings (Full-N). As for yield improvements and N limitation, soybean yield improvements from the 1980s to 2010s were documented, representing 29% increases in the US and 21% in ARG. Regarding N management, the Full-N fertilization produced a 12% increase in seed yields in the US and 4% in ARG. As for main seed N sources in objective two, remobilization accounted for 59% of seed N demand, and was negatively related to new N uptake occurring during the seed filling period. Seed N demand for greater yields was dependent on both, N remobilization and new N uptake, while for lower yields, seed N demand was mainly supported by the N remobilization process. These results suggest that: a) high seed yields are somehow limited by the availability of N to express their potential, although the question about N application still remains to be fully investigated, as related to the timing and the environment by plant interactions that could promote a N limitation in soybeans; b) remobilization accounts for majority (59%) of N sourced to the seed, and c) high yielding soybean (modern genotypes) rely on diverse N sources: the N remobilization process plus new uptake of N.

L'augmentation de la production d'huile de colza (Brassica napus L.) pour répondre à la demande alimentaire et industrielle exige d'optimiser le rendement dans un contexte de réduction des intrants, notamment azotés. Les approches de génétique offrent une voie pour répondre à ces enjeux. En effet, la connaissance des régions génomiques (QTLs) et des mécanismes qui contrôlent l'élaboration des composantes du rendement sous contrainte azotée est un prérequis à la création variétale. Dans ce contexte, les questions de recherche posées dans cette thèse sont les suivantes: i) quelle est l'architecture génétique du rendement en huile chez le colza cultivé en bas intrants azotés?, ii) quelles sont les interactions des QTLs avec l'environnement et plus particulièrement avec l'intensité du stress azoté?, et iii) comment la combinaison de données agronomiques, génétiques et génomiques peut-elle contribuer à l'amélioration de caractères d'intérêt chez le colza? Une stratégie de détection de QTLs par analyse de liaison et analyse d'association a été mise en place sur deux populations biparentales et un panel de colzas d'hiver. Ces populations ont été expérimentées sur sept lieux et six années de culture (2009-2014) en condition de nutrition azotée limitante ou suffisante. Pour chaque essai, sept caractères phénotypiques relatifs à l'élaboration du rendement ont été mesurés. Peu d'interactions génotype × azote ont été détectées sur les caractères étudiés et un nombre important de QTLs a été retrouvé dans les deux conditions azotées. A l'inverse, de fortes interactions génotype × environnement ont été mises en évidence pour la majorité des caractères et les QTLs étaient pour la plupart spécifiques d'un lieu de culture. Dix régions génomiques d'importance, stables entre environnement et populations ont ainsi été identifiés et leur organisation structurale dans le génome du colza a été analysée. Le contrôle génétique de la teneur en huile des graines de colza a ensuite été étudié en combinant à la fois les informations de dix études indépendantes, les informations procurées par la récente publication du génome de B. napus et la recherche de variabilité haplotypique dans une région d'intérêt identifiée sur le chromosome A1 dans une population de colzas d'hiver. / The increase of rapeseed (Brassica napus L.) oil production to answer the demand for human consumption and industrial applications requires the optimisation of seed yield in a context of reduction of inputs, including the nitrogen fertilization. Genetic approaches are a way to respond to this challenge. Indeed, determining the genomic regions (QTLs) and mechanisms controlling seed yield components under nitrogen limitation is a prerequisite for plant breeding programs. In this context, the scientific questions raised in this thesis are: i) what is the genetic architecture of seed yield components in rapeseed grown under limiting nitrogen condition? ii) how do the QTLs interact with the environment, and especially with the nitrogen stress?, and iii) how the combination of agronomic, genetic and genomic information can lead to the improvement of traits of interest in rapeseed? A strategy of QTL detection by linkage and linkage disequilibrium analyses was set up on two biparental populations and a winter oilseed rape diversity set. Those populations were trialled in seven location and six growing seasons (2009-2014) under low and sufficient nitrogen conditions. For each trial, seven seed yield-related traits were acquired. Few genotype × nitrogen condition interactions were detected and an important number of QTLs were common to the two nitrogen regimes. On the contrary, strong genotype × environment interactions were evidenced for most of the traits under study and the majority of the QTLs were location-specific. Ten critical genomic regions for yield associated traits stable through the environments and populations were identified and their structural organization in the rapeseed genome was investigated. The genetic control of oil content was then studied by combining the information from ten independent reports, the genomic information provided by the recent release of the B. napus genome and the haplotype variations among a winter oilseed rape population within one particular region identified on the A1 chromosome.

Meadow bromegrass (<i>Bromus riparius</i> Rehm.) is a recently introduced pasture grass in western Canada. Its leafy production and rapid regrowth have made it the most widely used grass species for pasturing beef animals in this region. As relatively little breeding work has been done on this species, there is little information on its breeding behaviour. The main objective of this study was to estimate genetic parameters and assess breeding methodologies for meadow bromegrass. Forty-four meadow bromegrass genotypes from the three available cultivars and forty half-sib (polycross (PX) and open-pollinated (OP)) and selfed (S1) progenies were evaluated for morphological and agronomic characters, and molecular (RAPD) markers. Genetic variation for total biological yield, head weight, seed yield, harvest index, height, growth habit, spread, and volume was significant in the OP and S1 tests. Genetic variation estimates for dry matter yield were negative (PX), not significant (OP), or moderate (S1). Estimated geneticvariation for quality traits and those characters which were visually evaluated was not significant, except for growth habit (OP and S1) and acid-detergent fiber (ADF) (S1). Among progeny lines, RAPD marker variation found in the half-sib progenies accounted for about 15% of the total variation. In the S1 test the variation among progeny lines was twice that of the half-sib progenies. Correlations between the different characters demonstrated that is possible to simultaneously improve both seed and forage yield. Since leafiness was found to be correlated with dry matter yield but not with seed yield it may be possible to simultaneously improve all three characters. Rankings of progenies by the half-sib tests for forage and seed yield were not changed by the use of the synthetic parental value (SVi) which includes information from selfed progeny. The PX progeny test did not discriminate parents as well as the OP and S1 tests, which may be due to non-random pollination in the polycross. The S1 progeny test showed the highest predicted response to selection, followed by the OP test. Heritability estimates from the OP and S1 tests for total biological yield, seed yield, harvest index, and height, were similar to those found in the clonal evaluation test. Therefore, a clonal evaluation test will provide sufficient information to choose parents for breeding an improved synthetic cultivar for these characters. Observed dissimilarity of ranking of progeny lines over progeny tests for some traits (head weight, seed yield, and harvest index) was due to discrepancies between the PX and OP tests. No differences in progeny line ranking among the progeny tests were observed for all other traits. Analysis of variance on marker frequency means showed that interaction between genotypes and progeny lines was also not significant.

Magistrantūros studijų baigiamojo darbo tyrimų tikslas buvo įvertinti skirtingų biologinių preparatų, kaip dirvos aktyvatorių, naudojamų rudenį ant priešsėlio (žieminių kviečių) ražienų, bei pavasarį, rapsams esant butonizacijos tarpsnyje, poveikį žieminių rapsų vystymuisi bei derliaus formavimuisi. Lauko eksperimentas buvo atliktas 2010–2011 m. ASU Bandymų stotyje. Dirvožemis IDg8-k (LVg-p-w-cc) – karbonatingas sekliai glėjiškas išplautžemis (Calc(ar)i-Epihypogleyic Luvisols). Darbo objektas – Žieminis rapsas (Brassica napus ssp. oleifera), linijinė veislė ‘Sunday’. Darbo metodai: Žieminių rapsų biometriniai matavimai, sėklų derlingumas bei derliaus struktūros elementai nustatyti tiesioginio matavimo, skaičiavimo ar svėrimo būdu pagal priimtas lauko eksperimento vykdymo metodikas. Tyrimų duomenys statistiškai įvertinti vieno veiksnio arba dviejų veiksnių kiekybinių požymių dispersinės analizės metodais, taikant kompiuterinę programą ANOVA (Tarakanovas, Raudonius, 2003). Darbo rezultatai. Esmingai didžiausias žieminių rapsų šaknies kaklelio skersmuo (13 mm) prieš augalų žiemojimą nustatytas variante, kur ant žieminių kviečių ražienų buvo išpurkštas biologinių preparatų Azofit (1,0 l ha-1) ir Amalgerol (3,0 l ha-1) derinys. Šiame variante peržiemojo 9,73 % daugiau augalų nei kontroliniame. Esmingai didžiausias žieminių rapsų sėklų derlingumas (3,25 t ha-1) gautas variante, kuriame Azofit (1,0 l ha-1) ir Amalgerol (3,0 l ha-1) derinys išpurkštas rudenį ir pavasarį, tai 1,5 t... [toliau žr. visą tekstą] / The main objective of Master thesis research was to evaluate various biological agents, as soil activators, which are used in the fall on the preceding crop (winter wheat) stubble and in spring on rape at bud formation stage, and the impact that these biological agents do to winter rapeseed crop development and formation. Field experiment was conducted in 2010–2011 at ASU Experimental Station. The soil type – Calc(ar)i-Epihypogleyic Luvisols (LVg-p-w-cc). The object – winter rape (Brassica napus ssp. Oleifera) linear sort 'Sunday'. Working methods: biometric measurements of winter rape, seed yield and yield structure elements were determined while using direct measurements, calculations or weighing according field experimental techniques. Research data have been statistically evaluated with a single factor or two factor analysis of variance of quantitative methods of evidence, using a computer program ANOVA (Tarakanovas, Raudonius, 2003). Research results. The biggest winter rape root collar diameter (13 mm) before winter was found in variant, where the winter wheat stubble was sprayed with the combination of biological preparations Azofit (1.0 l ha-1) and Amalgerol (3.0 l ha-1). In this variant 9.73% more plants survived winter than in control field. The biggest winter rapeseed yield (3.25 t ha-1) was obtained in the variant where a combination of Azofit (1.0 l ha-1) and Amalgerol (3.0 l ha-1) was sprayed in the autumn and spring, it was 1.5 t ha -1 higher than in the... [to full text]

Lodgepole pine (Pinus contorta Douglas ex Louden) is the most widespread pine in North America and the single most abundant tree species in British Columbia (BC). Its vast distribution, diversity and economic value make it an important species for timber harvest and subsequent reforestation. Climate change raises serious concerns over the adaptability and effective management of BC’s future forests. The majority of lodgepole pine seedlings requested for replanting are produced from seed obtained from wild stands, but the relationship between climate variation and the seed production of natural populations has yet to be assessed. The purpose of this study is to determine if variation in P. contorta seed yield is related to the climate of BC. Historical cone collection data were obtained from archived records of 1948 seedlots in 22 different natural stand seed planning zones (SPZs) of BC. Collections were made between 1963 and 2013 and seed yield (kg fresh seed/hL cone) was determined for each seedlot. First, natural variation in seed production of lodgepole pine was examined in 18 different SPZs. The Nass Skeena Transition (NST) represents a unique intersection between continental and maritime ecosystems and was found to have a significantly higher mean seed yield compared to all other zones, with the exception of Hudson Hope (HH). However, variance in seed yield for NST was found to be an order of magnitude higher than that of other SPZs, indicating that seed production in this region is exceptionally variable. These findings provide a valuable geographic baseline for the reproductive fitness of lodgepole pine, suggesting that climate adaptation and mitigation strategies for some areas of the province may need to be region-specific. In addition, the relationship between climate variation and the seed production of P. contorta in BC was evaluated. The climate of each region was described using dynamically-downscaled Global Circulation Model (GCM) and reanalysis climate output from the Canadian Regional Climate Model (CRCM). Annual, winter, and summer means were explored for each of the climate variables of interest: total precipitation (mm) and surface air temperature (°C). Temporal correlations between the mean annual seed yield anomaly and the anomaly of both climate variables were significant under a variety of climate schemes in a number of SPZs. Significant overall trends in climate variables were also captured using GCM-driven CRCM output. While these two analyses independently highlighted significant relationships between seed yield and climate, their joint implications were unclear. Shifts in the CRCM boundary conditions revealed that the results lacked robustness during the historical period, inhibiting the investigation of future projections. Ambiguous age ranges for each cone collection and temporal restrictions of the seed collection data may be partially responsible for these inconclusive results. Results from the first half of this thesis suggest that, with few exceptions, seed production is relatively stable across SPZs spanning a wide range of climate regimes. Thus, the investigation of the relationship between reproductive fitness and climate may be complicated by the extraordinary adaptability of lodgepole pine and the high genetic variation in natural populations. / Graduate

Orientador: Marco Eustáquio de Sá / Resumo: Conhecendo as condições climáticas da região, fazendo a escolha correta das espécies de plantas de cobertura e do sistema de cultivo, pode-se melhorar a qualidade do solo e favorecer a cultura sucessora. O objetivo nesse trabalho foi avaliar o efeito da adubação verde e doses de estimulantes em plantio direto, no desenvolvimento, produtividade e qualidade fisiológica das sementes do feijão cultivar BRS Estilo, no cerrado Sul-Mato-Grossense. Foram preparados dois experimentos distintos, o primeiro com o estimulante GeoRaiz Gram e o segundo com o estimulante Bacillus subtilis, no delineamento de blocos casualizados, em esquema fatorial 4 x 4, quatro doses: 0, 200, 400 e 600mL 50kg-1sementes dos estimulantes e quatro espécies de plantas de cobertura: Crotalaria spectabilis, Pennisetum glaucum, Crotalaria juncea e Urochloa ruziziensis. Os experimentos foram conduzidos na Fazenda de Ensino, Pesquisa e Extensão da Universidade Estadual Paulista FE/UNESP, localizada em Selvíria-MS, no ano agrícola de 2016. As espécies de gramíneas e leguminosas foram semeadas no dia 18 de março no sentido oposto aquele determinado para a semeadura direta do feijão, realizada em 01 de junho, aos 72 dias, 8 dias após a dessecação da palhada das plantas de cobertura, visando a população de 333.333 plantas ha-1. Os parâmetros avaliados foram: massa verde; massa seca das plantas e determinação do teor de macronutrientes, micronutrientes e proteína bruta da massa seca das culturas de cobertura; quantidade... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Knowing the climatic conditions of the region, making the correct choice of cover crop species and the cultivation system, can improve the quality of the soil and favor the successor crop. The objective of this study was to evaluate the effect of green manuring and stimulant doses in no-tillage, in the development, productivity and physiological quality of the BRS Estilo common bean seeds in the cerrado Sul-Mato-Grossense. Two distinct experiments were prepared, the first with the GeoRaiz Gram stimulant and the second with the stimulant Bacillus subtilis, in a randomized block design in a factorial 4 x 4, four doses: 0, 200, 400 and 600ml 50kg-1 seeds of the stimulants and four species of cover plants: Crotalaria spectabilis, Pennisetum glaucum, Crotalaria juncea and Urochloa ruziziensis. The experiments were conducted at the Fazenda de Ensino, Pesquisa e Extensão of the São Paulo State University FE/UNESP, located in Selvíria-MS, in the grown season of 2016. The species of grasses and legumes were sown on March 18 in the opposite direction to that determined for direct sowing of the bean, held on June 1, at 72 days, 8 days after the desiccation of the straw from the cover crops, targeting the population of 333.333 plants ha-1. The evaluated parameters were: green mass; dry mass of plants and determination of the macronutrient, micronutrient and crude protein content of the dry mass of cover crops; amount of carbon; C/N ratio; in the bean plant, initial stand; chlorophyll con... (Complete abstract click electronic access below) / Doutor

Submitted by MATHEUS ELACHE ROSA null (matheus26elache@bol.com.br) on 2018-02-19T00:11:18Z No. of bitstreams: 1 rosa_me_dr_ilha.pdf: 4016467 bytes, checksum: 338d1449292ffa218fd4a2f6de536b71 (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2018-02-19T12:56:12Z (GMT) No. of bitstreams: 1 rosa_me_dr_ilha.pdf: 4016467 bytes, checksum: 338d1449292ffa218fd4a2f6de536b71 (MD5) / Made available in DSpace on 2018-02-19T12:56:12Z (GMT). No. of bitstreams: 1 rosa_me_dr_ilha.pdf: 4016467 bytes, checksum: 338d1449292ffa218fd4a2f6de536b71 (MD5) Previous issue date: 2018-01-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Conhecendo as condições climáticas da região, fazendo a escolha correta das espécies de plantas de cobertura e do sistema de cultivo, pode-se melhorar a qualidade do solo e favorecer a cultura sucessora. O objetivo nesse trabalho foi avaliar o efeito da adubação verde e doses de estimulantes em plantio direto, no desenvolvimento, produtividade e qualidade fisiológica das sementes do feijão cultivar BRS Estilo, no cerrado Sul-Mato-Grossense. Foram preparados dois experimentos distintos, o primeiro com o estimulante GeoRaiz Gram e o segundo com o estimulante Bacillus subtilis, no delineamento de blocos casualizados, em esquema fatorial 4 x 4, quatro doses: 0, 200, 400 e 600mL 50kg-1sementes dos estimulantes e quatro espécies de plantas de cobertura: Crotalaria spectabilis, Pennisetum glaucum, Crotalaria juncea e Urochloa ruziziensis. Os experimentos foram conduzidos na Fazenda de Ensino, Pesquisa e Extensão da Universidade Estadual Paulista FE/UNESP, localizada em Selvíria-MS, no ano agrícola de 2016. As espécies de gramíneas e leguminosas foram semeadas no dia 18 de março no sentido oposto aquele determinado para a semeadura direta do feijão, realizada em 01 de junho, aos 72 dias, 8 dias após a dessecação da palhada das plantas de cobertura, visando a população de 333.333 plantas ha-1. Os parâmetros avaliados foram: massa verde; massa seca das plantas e determinação do teor de macronutrientes, micronutrientes e proteína bruta da massa seca das culturas de cobertura; quantidade de carbono; relação C/N; no feijoeiro, estande inicial; teor de clorofila das folhas; comprimento da raiz principal; componentes de produção: número de vagens por planta, número de sementes por vagem, número de sementes por planta, massa de 100 sementes, massa da palha, relação grão/palha, teor de nutrientes das sementes e produtividade; estande final; qualidade fisiológica de sementes: teste de germinação, primeira contagem, segunda contagem, matéria seca, índice de velocidade de germinação, comprimento da parte hipocótilo e raiz, teste de condutividade elétrica, teste de envelhecimento acelerado, teste de frio e teor de água dos grãos. Com base nos resultados, verificou-se que as plantas de cobertura Crotalaria juncea e Pennisetum glaucum proporcionaram maior volume de massa seca e elevado aporte de nutrientes para o cultivo de feijoeiro, em sistema de plantio direto. A inoculação das sementes de feijão com os estimulantes GeoRaiz Gram e Bacillus subtilis não proporcionaram ganho em produtividade do feijoeiro. As sementes produzidas apresentaram alta qualidade fisiológica, com excelente capacidade germinativa e alto vigor, indicando que os tratamentos favoreceram ao feijoeiro a condição de produção de sementes de alta qualidade. / Knowing the climatic conditions of the region, making the correct choice of cover crop species and the cultivation system, can improve the quality of the soil and favor the successor crop. The objective of this study was to evaluate the effect of green manuring and stimulant doses in no-tillage, in the development, productivity and physiological quality of the BRS Estilo common bean seeds in the cerrado Sul-Mato-Grossense. Two distinct experiments were prepared, the first with the GeoRaiz Gram stimulant and the second with the stimulant Bacillus subtilis, in a randomized block design in a factorial 4 x 4, four doses: 0, 200, 400 and 600ml 50kg-1 seeds of the stimulants and four species of cover plants: Crotalaria spectabilis, Pennisetum glaucum, Crotalaria juncea and Urochloa ruziziensis. The experiments were conducted at the Fazenda de Ensino, Pesquisa e Extensão of the São Paulo State University FE/UNESP, located in Selvíria-MS, in the grown season of 2016. The species of grasses and legumes were sown on March 18 in the opposite direction to that determined for direct sowing of the bean, held on June 1, at 72 days, 8 days after the desiccation of the straw from the cover crops, targeting the population of 333.333 plants ha-1. The evaluated parameters were: green mass; dry mass of plants and determination of the macronutrient, micronutrient and crude protein content of the dry mass of cover crops; amount of carbon; C/N ratio; in the bean plant, initial stand; chlorophyll content of leaves; length of the main root; production components: number of grain beans per plant, number of seeds per pods beans, number of seeds per plant, mass of 100 seeds, straw mass, grain/straw ratio, seed nutrient content and yield; final stand; physiological seed quality: germination test, first count, second count, dry matter, speed germination index, length of the hypocotyl and root part, electrical conductivity test, accelerated aging test, cold test and water content of the grains. Based on the results, it was verified that the cover plants Crotalaria juncea and Pennisetum glaucum provided higher volume of dry mass and high nutrient intake for bean cultivation, in no-tillage system. The inoculation of the common bean seeds with the GeoRaiz Gram and Bacillus subtilis stimulants did not provide gain in bean productivity. The seeds produced presented high physiological quality, with excellent germinative capacity and high vigor, indicating that the treatments favored the common bean to the condition of producing high quality seeds.

Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2018-06-28T16:28:06Z No. of bitstreams: 1 Ricardo Pereira da Cunha.pdf: 3361190 bytes, checksum: 4e63765af298f88e293b3178ab1b4043 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-07-03T18:40:52Z (GMT) No. of bitstreams: 1 Ricardo Pereira da Cunha.pdf: 3361190 bytes, checksum: 4e63765af298f88e293b3178ab1b4043 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-07-03T18:42:58Z (GMT) No. of bitstreams: 1 Ricardo Pereira da Cunha.pdf: 3361190 bytes, checksum: 4e63765af298f88e293b3178ab1b4043 (MD5) / Made available in DSpace on 2018-07-03T18:43:08Z (GMT). No. of bitstreams: 1 Ricardo Pereira da Cunha.pdf: 3361190 bytes, checksum: 4e63765af298f88e293b3178ab1b4043 (MD5) Previous issue date: 2017-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / O azevém anual cultivar BRS Integração, no Sul do Brasil, em solos hidromórficos, diferencia-se dos demais, especialmente por apresentar alta produtividade de forragem de boa qualidade em um ciclo produtivo mais curto. Característica fundamental para a integração com lavouras de estação quente. No entanto, são poucas as informações sobre respostas desta cultivar ao manejo de desfolha e produção de sementes de alta qualidade. Neste sentido, foi conduzido um experimento no Sul do Rio Grande do Sul sobre solos hidromórficos das terras baixas para verificar a influência da frequência, intensidade de desfolha e dose da adubação nitrogenada sobre a produção e a qualidade da semente da cultivar BRS Integração. Foram testadas duas frequências de desfolha (duas e três desfolhas), duas intensidades de desfolha (7,5 e 15cm de altura do resíduo) e, após a última desfolha, foram testados diferentes níveis de adubação nitrogenada (50; 100; 150 e 200kg.ha-1). O delineamento foi em faixas para o fator adubação e os manejos de desfolha foram alocados ao acaso dentro das faixas. Os dados foram submetidos à análise de variância, comparação de médias pelo teste Tukey e regressão polinomial para descrição do fator nitrogênio, ambas ao nível de 5% de probabilidade. A execução da terceira desfolha mantendo 7,5cm de altura residual, prejudica o rendimento e a qualidade fisiológica da semente, bem como, a execução da terceira desfolha mantendo 15cm de altura residual possibilita alto potencial de resposta da planta para a produção de sementes de alta qualidade, desde que suprida a necessidade de nitrogênio. / The annual ryegrass BRS Integration, in the South of Brazil, in hydromorphic soils, differs from the others, especially because it presents high productivity of good quality fodder in a shorter productive cycle. Key feature for integration with hot season crops. However, there is few information on the responses of this cultivar to the management of defoliation and production of high quality seeds. In this sense, an experiment was carried out in the south of Rio Grande do Sul on lowland hydromorphic soils to verify the influence of frequency, defoliation intensity and nitrogen fertilization dose on the production and seed quality of BRS Integration. Two defoliation frequencies (two and three defoliation), two defoliation intensities (7,5 and 15cm height of the residue) were tested and, after the last defoliation, different levels of nitrogen fertilization (50, 100, 150 and 200kg.ha-1). The design was in bands for the fertilization factor and the defoliation maneuvers were randomly allocated within the ranges. The data were submitted to analysis of variance, comparison of means by Tukey test and polynomial regression to describe the nitrogen factor, both at the 5% probability level. The execution of the third defoliation, maintaining 7,5cm of residual height, impairs the yield and the physiological quality of the seed, as well as, the execution of the third defoliation, maintaining 15 cm of residual height, allows high plant response potential for high seed production quality.

Nas últimas décadas, a podridão vermelha das raízes da soja (PVR), causada pelo Fusarium solani f.sp. glycines (FSG), tornou-se uma doença séria nas regiões brasileiras onde já foi constatada, sendo a utilização de cultivares resistentes um componente fundamental de um sistema integrado de controle. Este trabalho teve por objetivo pesquisar estratégias de seleção de genótipos resistentes a PVR. Várias metodologias foram implementadas: avanço de progênies até a geração F7:2 e seleção em campo infestado, de progênies selecionadas em F2. Avaliou-se o cruzamento IAC 4 x Conquista em casa de vegetação (geração F3:2) e em campo infestado (gerações F3:2, F4:2 e F5:2), através de estudo de estabilidade e adaptabilidade das progênies. As metodologias de infecção em vasos de barro e bandejas de isopor em casa de vegetação foram comparadas para melhorar a eficiência de seleção; também foi feita análise de repetibilidade dos sintomas foliares da PVR, para otimização do número de avaliações necessárias para classificar o genótipo de soja quanto à reação ao FSG. Cultivares brasileiras de soja foram avaliadas em campo infestado. Em campo, as plantas foram avaliadas no estádio R5-6, com notas variando de 1 (ausência de sintomas) a 5 (100% da raiz principal com sintomas). Em casa de vegetação, as plantas foram avaliadas aos 35 dias pós-semeadura para sintomas radiculares e da parte aérea. Houve eficiência da seleção para resistência a PVR tanto em F2 (sintomas foliares em casa de vegetação) quanto em F7:2 (sintomas radiculares em campo naturalmente infestado). A seleção praticada nas gerações intermediárias também foi eficiente para aumentar a produtividade de grãos das progênies. Para o cruzamento IAC 4 x Conquista nas gerações F3:2, F4:2 e F5:2 em campo naturalmente infestado e na F3:2 em casa de vegetação, a metodologia de Annicchiarico possibilitou a seleção de genótipos com maior estabilidade e adaptabilidade para os diferentes ambientes; com o estudo genético destas gerações, demonstrou que há efeitos gênicos aditivos e dominantes no controle genético da PVR. Além disso, constatou-se que os genes responsáveis pela resistência estão dispersos nos genitores, provavelmente agrupados em blocos gênicos. A presença de dominância indica que a seleção deve ser postergada para gerações com maior homozigose (linhagem pura); esta idéia foi reforçada pela baixa herdabilidade ao nível de plantas. O uso de bandejas de isopor foi significativamente mais eficiente do que vasos de barro para inoculação de FSG em casa de vegetação. Pela análise de repetibilidade, detectou-se que quatro avaliações foram suficientes para discriminar se o genótipo era realmente suscetível ao FSG. A correlação da geração F3:2 (IAC 4 x Conquista) entre campo infestado e casa de vegetação foi praticamente nula; no entanto, 54% das progênies selecionadas em campo também foram selecionadas em casa de vegetação. A seleção de genótipos superiores para resistência ao FSG não é tarefa fácil, mas pode ser aprimorada pelo uso conjugado de metodologias suplementares que aumentem a eficiência de seleção. / During the last decades, soybean sudden death syndrome (SDS), caused by Fusarium solani f.sp. glycines (FSG), has become a serious disease in the regions where it was encountered. The use of resistant soybean cultivars has been an important component of an integrated management system. The aim of this work was to research selection strategies of SDS-resistant genotypes. A number of methodologies were used: self pollination up to generation F7:2 and progeny selection in infested field of selected F2. The crossing IAC 4 x Conquista was studied in greenhouse (generation F3:2) and in a naturally infested field (generations F3:2, F4:2 and F5:2), where the progeny stability and adaptability study was carried out. The methodologies of infection in clay pots and polystyrene trays in greenhouse were compared to improve selection efficiency. An analysis of the repeatability of foliar SDS symptoms was also performed in order to optimize the number of evaluations needed to classify a soybean genotypes reaction to FSG. Brazilian soybean cultivars were evaluated in a naturally infested field, where plants were evaluated at stage R5-6 with scores varying from 1 (absence of symptoms) to 5 (main root 100% symptoms). In the greenhouse, the plants were evaluated 35 days after sowing for root symptoms, while the leaf symptoms was only evaluated after the appearance of symptoms. The selection done in F2 (leaf symptoms in greenhouse) as well as F7:2 (root symptoms in infested field) for FSG were efficient. The selections performed in intermediary generations were efficient in increasing the grain yield of the progeny. Studies of the F3:2, F4:2 and F5:2 generations of the IAC 4 x Conquista cross in an infested field and F3:2 in greenhouse, enabled through Annicchiaricos methodology, the selection of genotypes with greater stability and adaptability to different environments. The genetic study of these generations demonstrated there are additive and dominant genetic effects on the genetic control of SDS. Moreover, it was noted that the genes responsible for resistance are dispersed on the genitors, probably grouped into genic blocks. The presence of dominance indicates that the selection should be passed onto generations with greater homozygosity. There is also a clear indication that breeders should work with progeny lines in order to assist selection due to the low inheritability at the individual plant level. For the experiments with different FSG inoculation methodologies (clay pots and polystyrene trays) in greenhouse the use of trays was significantly more efficient; by studying the repeatability analysis, it was found that four evaluations is enough to discriminate if the genotype is really susceptible to FSG. The correlation of the F3:2 generation (IAC 4 x Conquista) between infested field and greenhouse was practically null; however, 54% of the progeny selected in the field were selected in greenhouse. As observed, the selection of superior genotypes for FSG resistance is not an easy task, but may be improved by means of new methodologies and the conjugated use of methodologies which improve selection efficiency.

A ferrugem da soja (Phakopsora pachyrhizi Sydow e Sydow) foi constatada pela primeira vez no Brasil na safra 2000/01, e representa até o momento, um importante desafio para os programas de melhoramento genético de soja. As cultivares e linhagens inicialmente identificadas como resistentes, tiveram sua resistência quebrada já na safra 2002/03, pela ocorrência de prováveis novas raças do patógeno. Por consequência, a longevidade da resistência genética vertical foi colocada em risco, e o desenvolvimento de trabalhos através da utilização da tolerância é a alternativa. Como suporte para a manutenção da longevidade do controle genético da ferrugem, este trabalho objetivou testar estratégias de seleção de genótipos de soja para tolerância à ferrugem, na ausência de genes principais de resistência. Os experimentos foram conduzidos durante os anos agrícolas 2004/05 e 2005/06 em diferentes locais administrados pelo Departamento de Genética, ESALQ/USP, município de Piracicaba, SP. Foi utilizado o delineamento experimental de blocos casualizados com repetições estratificadas em conjuntos experimentais e testemunhas comuns aos conjuntos experimentais. Em 2004/05, no local Anhembi, 60 linhagens experimentais mais quatro testemunhas suscetíveis à ferrugem (BR-16, FT-2000, Conquista e IAC-100), foram avaliadas em três experimentos com e sem fungicidas (Controle, Derosal e Impact). Em 2005/06, as 26 melhores linhagens para tolerância à ferrugem, selecionadas em 2004/05, foram novamente avaliadas através dos três experimentos (Controle, Derosal e Impact) juntamente com as testemunhas (BR-16, IAC-100 e BRS-232), nos locais Anhembi, ESALQ e Areão. Contrastes das médias de produtividade de grãos entre os experimentos de fungicidas, e uma adaptação do modelo de regressão de Eberhart e Russel, foram utilizados para medir a ação da ferrugem e das doenças de final de ciclo (DFC) sobre as linhagens, com o intuito de realizar seleção de linhagens tolerantes. A ferrugem reduziu a produtividade de grãos mas não alterou significativamente o ciclo e o peso de mil sementes, bem como não alterou as outras características agronômicas estudadas. As duas estratégias de seleção propostas e utilizadas neste trabalho, foram eficientes para separar os efeitos das doenças (ferrugem e DFC), e identificar e selecionar genótipos tolerantes na ausência de genes principais de resistência, viabilizando a seleção de linhagens tolerantes. Houve associação entre tolerância à ferrugem, DFC e resistência ao nematóide de cisto da soja. / Soybean rust (Phakopsora pachyrhizi Sydow and Sydow) was first recorded in Brazil during the 2000/01 season and, even today, represents an important challenge to soybean breeding. The cultivars and lines initially identified as resistant had their resistance breakdown on the 2002/03 season, probably by the occurrence of new races of the pathogen. Consequently, the longevity of the vertical genetic resistance was put in risk and the development of works through the use of tolerance is the alternative. As support for the maintenance of the longevity of the genetic control of rust, this work aimed to evaluate strategies for selection of genotypes to rust tolerance in the absence of major resistance genes. The experiments were conducted during the agricultural years of 2004/05 and 2005/06 in different locations administered by the Department of Genetics ESALQ/USP, Piracicaba, SP. It was used the randomized complete-block design with replications stratified in experimental sets with common checks. In 2004/05 at Anhembi, 60 experimental lines and four rust-susceptible checks (BR-16, FT-2000, Conquista and IAC- 100), were evaluated in three experiments with and without fungicides (Control, Derosal and Impact). In 2005/06, the 26 best lines for rust tolerance, selected in 2004/05, were evaluated again through the three experiments (Control, Derosal and Impact) together with the checks (BR-16, IAC-100 and BRS-232), in the locations Anhembi, ESALQ and Areão. Contrasts of seed yield means among the fungicide experiments, and an adaptation of the regression model of Eberhart and Russel, were used to measure the action of rust and late season leaf diseases (LSLD) on the lines, with the intention of selecting tolerant lines. Rust reduced the seed yield but did not significantly alter the cycle or the weight of one thousand seeds, just as there was no significant change in other agronomical traits studied. Both selection methodologies were efficient to separate the effects of the diseases (rust and LSLD) and identify and select tolerant genotypes at the absence of major resistance genes, enabling the selection of tolerant lines. There was an association between rust, LSLD tolerance and soybean cyst nematode resistance.