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The objective of this work was to assess the breeding influences in different agronomic and physiological traits in Brazilian soybean cultivars, released between 1965 and 2011, to identify traits associated with modern cultivars. A total of 29 cultivars were evaluated in two locations in the 2016/17 crop season. Genotype selection based on agronomic and physiological traits was determined using GYT (Grain Yield*Trait) methodology, which uses the Superiority Index to rank genotypes by mean of all traits. Grain Yield is combined with other target traits and shows the strengths and weaknesses of each genotype. Soybean breeding improved desirable traits during the 46 years of evaluation. Superiority index can be a powerful tool for breeders to obtain high genetic gains in the future. The cultivars DMario 58i, TMG 7161RR and TMG 7262 RR stand out as the best cultivars but present different sets of desirable traits. The traits grain yield, harvest index, number of pods per plant, reproductive-vegetative ratio, photosynthetic rate and transpiration rate are core traits which can be evaluated in soybean breeding programs.

This study aimed to identify important traits for indirect selection and to evaluate the variability among black oat populations through cause and effect relationships and canonical variables. Fourteen (14) black oat populations were collected in the 2013 cropping season which were evaluated in the laboratory, and then in the field in the 2014 cropping season. The seed width has a high and positive association with physiological quality of black oat seeds. The number of grains and thousand-grain weight has greater direct effects on the grain yield of black oat; thus, these traits may be considered for indirect selection in earlier phases of future black oat breeding programs. Targeted crosses between black oat genotypes coming from Salvador das Missoes with genotypes coming from the other studied locations should be promising to obtain recombinant offspring in the future.

The aims of this study were to characterize black oat populations by estimating between- and within-populations variance components and genetic parameters, as well as to distinguish the populations using multivariable statistics. The experiment was carried out in randomized blocks design with three repetitions, with 14 black oat populations collected in several municipalities of Rio Grande do Sul state. Agronomic important traits were assessed at physiological maturation stage. Variance components and genetic parameters were estimated considering within-block information. In addition, Mahalanobis distance, relative contribution of traits, and canonical variables were used to distinguish the populations. Selection based on panicle length, number of grains per panicle, panicle weight and panicle grain weight may result in higher selection gains. Panicle grain weight presents a greater contribution to genetic divergence between studied populations. The formation of distinct groups indicated the presence of genetic variability among black oat populations in the northwestern of the Rio Grande do Sul state. Directed crosses between individual plants of populations from (i) Alto Alegre and Salvador das Missoes, Chapada, or Santa Rosa or (ii) between plants of populations from Salvador das Missoes and Campos Borges or Santa Rosa can generate segregating populations with great genetic variability. The predominance of between-phenotypic variance and a within-genetic variance indicate prospects for success in selection gain and possible selection of a new cultivar with fewer efforts compared to a cross-based method. This is supported by the high values of within-population heritability.

System fertilization is characterized by partial or total fertilizer application at the predecessor crop; and it can be a viable practice to soybean crop. This study aimed to determine the fertilizer management and fertilizer levels for black oat-soybean cropping system, in high fertility soils and no-tillage system. The field trial was conducted in a bifactorial scheme, consisting of six environments, by combination of locations (Bom Sucesso do Sul - Paraná, Itapejara d'Oeste - Paraná) and fertilization management (all fertilization in black oat; splitting with 50% in black oat and 50% in soybean, all fertilization in soybean), and four fertilizer levels (0, 100, 200 and 300%) defined according to soil analysis and production expected. The evaluated traits were dry mass production, N, P and K nutrient accumulation of straw, dry mass remaining of black oat crop; and plant height, number of pods per plant, thousand grain weight, grain yield for soybean crop. Higher black oat dry mass production was observed at higher fertilization level. The fertilizer anticipation in black oat crop had better performance. Phosphorus and potassium accumulation increased linearly with fertilizer level increase. For N, the highest accumulated value occurred at the 200%, decreasing at the 300% of fertilizer level. The soybean crop had no influence in grain yield considering fertilization management, anticipation or splitting, and fertilizer levels. Thus, the system fertilization can be a viable practice, and favor black oat dry mass production and soybean development.

The cultivation of second-harvest with soybean crop after first-harvest with maize crop has become an alternative to aggregate income to farmers in the South region of Brazil. However, there is little information about this cropping system in this region. The aims of this study were to: (i) evaluate the agronomic performance of soybean (Glycine max L.) cultivars growing in second-harvest during the summer; and (ii) evaluate the genetic divergence of the cultivars based on qualitative and quantitative traits. To do this, 18 soybean cultivars were evaluated in three field trials, sown during January in the northwestern region of Rio Grande do Sul state, Brazil. In each experiment, a randomized block design with four replicates was used. Five quantitative traits (representing the agronomic performance of the cultivars) and 12 qualitative traits (morphological descriptors) were assessed aiming at studying the genetic divergence. Variance components and genetic parameters were estimated using mixed models and BLUPs for genotypes were estimated for each quantitative trait. The cultivars FPS Iguaçu RR and BMX Turbo RR have good agronomic performance and are, based on quantitative and qualitative traits, genetically distant. These cultivars have shown agronomic features that allow their cultivation in the second-harvest in the northwestern of Rio Grande do Sul in addition to be potential genitors for future soybean breeding programs.

In Brazil, common bean (Phaseolus vulgaris L.) is cultivated in different growing seasons and environments, with different genotypes responses due to the genotype x environment interaction. This study aimed to identify common bean genotypes with a better production stability in each growing environment. The trials were conducted in a randomized block design, with three replications, involving three growing years, nine common bean genotypes and four environments (first and second growing seasons with high and low levels of technological input, such as fertilizers and pest and disease control). Biplot analyses were performed using the GGE Biplot software. The use of high levels of technological input results in an average increase of 14.4 % for yield and is more representative in the crop environments, as well as more adequate for genotype selection. IPR Campos Gerais, BRS Esplendor and BRS Campeiro showed a high stability and presented the best productive performance under both technological levels. RESUMO No Brasil, o feijoeiro (Phaseolus vulgaris L.) é cultivado em diferentes safras e ambientes, com diferentes respostas do genótipo devido à interação genótipo x ambiente. Objetivou-se identificar genótipos de feijão com melhor estabilidade produtiva em cada ambiente de cultivo. Os experimentos foram conduzidos em delineamento de blocos casualizados, com três repetições, envolvendo três anos agrícolas, nove genótipos de feijão comum e quatro ambientes (primeira e segunda safras com baixo e alto nível tecnológico de insumos, como fertilizantes, controle de pragas e doenças). Análises biplot foram realizadas utilizando-se o software GGE Biplot. O uso de alto nível tecnológico de insumos resulta em aumento de 14,4 % na produtividade, é mais representativo nos ambientes de cultivo e mais adequado para a seleção de genótipos. IPR Campos Gerais, BRS Esplendor e BRS Campeiro mostraram alta estabilidade e obtiveram o melhor desempenho produtivo em ambos os níveis tecnológicos.

Wheat is one of the most important cereal crops in the world. The objectives of this study were: (i) to evaluate the solvent retention capacity of wheat flour from three genotypes when nitrogenous fertilizer is applied at different stages of crop growth; and (ii) to evaluate the possible existence of correlations between different solvents when nitrogenous fertilizer is applied at different stages of crop growth. The experiment was conducted from June to November 2013 in Plant Breeding Laboratory and Plant Production, Federal University of Santa Maria, the experimental area is located at Frederico Westphalen, southern Brazil. The experiment consisted of 12 treatment combinations (3 genotypes and application of nitrogenous fertilizer at 4 crop growth stages) of a 3x4 factorial (genotype x nitrogenous fertilizer application) arranged in a randomized complete block design with three replications. The genotypes Fundacep 52, TBIO Mestre and TBIO Itaipu were arranged with the tested nitrogenous fertilizer applications (I = no nitrogen, II = tillering, III = tillering and flowering and IV = tillering, booting and flowering). Greater levels of solvent retention capacity were observed in TBIO Mestre, suggesting that the genotype has good baking quality. The amount of glutenin was not affected by the stage of nitrogenous fertilization application. The water retention capacity of the flour has a strong and positive correlation with the retention capacity of the sodium carbonate and sucrose, along with the associations between the solvents sodium carbonate and sucrose. Key words: Agriculture science, plant management, plant science, quality grains, Triticum aestivum L.

The objective of this study was to evaluate the induction of genetic variability and plant development of palisade grass (Urochloa brizantha L.) M2 mutants in acclimatization to subtropical climate condition. The mutagenic agent methyl methanesulfonate (MMS), at a dosage of 0.5%, was used to induce mutation in 4,000 seeds of the cultivar Marandu. Thirty five plants survived after the induction of MMS mutagen agent. These plants were isolated transplanted in experimental area to advance the generation. Seeds produced by plants were sown in pots allocated in Biosystems Organized Development incubator and subjected to cold stress at 0°C in seedling stage. Surviving seedlings per family were transplanted to field conditions in Southern Brazil. The plant development was evaluated in the M2 generation during the agricultural years of 2012-2013 and 2013-2014. Genetic variability analyzes were carried out with 21 traits, based on the average Euclidean distance and the relative contribution proposed by Singh (1981). Chemical mutation induction with MMS generates genetic variability in palisade grass, enhancing the selection of superior genotypes in subtropical climate conditions. The chemical induction of mutations with the MMS mutagen provided genetic variability in the population of U. brizantha with formation of 18 divergent groups during the research. Key words: Urochloa brizantha L., plant breeding, genetic recombination, forage, multivariate analyses.

The objective of this work was to verify physiological quality of black oat populations, in order to know and point out the relationships among physiological characters for selection of progenies. The experiment was carried out at the Laboratory of Plant Breeding and Production, Federal University of Santa Maria, Campus of Frederico Westphalen - RS. Seed samples were collected from 14 black oat populations from small producers in the region, and cultivars BRS Madrugada and BRS Centauro (populations 15 and 16, respectively). A randomized block design with four replications was used. It was evaluated seed length, seed width, thousand seed weight, percentage of germination, non-germinated seeds, abnormal seedlings, hypocotyl length, root length, dry matter of seedlings. Populations revealed a difference in the physiological quality of seeds, and populations 1, 8, 9, 11, 12, 13, with germination within the required standard, have a greater potential to compose progenies. Seed width, thousand seed weight, dry matter of seedlings and hypocotyl length revealed association with germination. It is worth highlighting that seed width and thousand seed weight are characters of easy and immediate measurement that can guarantee greater efficiency of selection.

This work aimed to determine variance components and genetic parameters, as well as phenotypic, genetic and environmental correlations among black oat (Avena strigosa) families grown in different crop season. Seventy-six black oat families and three controls (BRS Madrugada, BRS Centauro, BRS 139 Neblina) were evaluated in two crop seasons (2016 and 2017), using families with intercalary controls experimental design. The results reveled high potential of black oat families to compose a breeding program, due to families and controls variance were similar, variance components expressed greater genetic variance origin for crop season. Panicle weight and panicle grain weight presented high heritability and, these are correlated with panicle length. Thus, these traits can be used to select superior genotypes. Divergent meteorological conditions between crop seasons expressed few variations among phenotypic, genetic and environmental correlations, and it did not alter magnitude and sense of phenotypic and genetic correlations.