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AbstrAct:The increase of yield potential in new rice (Oryza sativa L.) varieties has been a major challenge for genetic improvement.The generation of mutants, followed by their characterization, constitutes a great possibility to isolate and select genes and genotypes that present agronomic traits of interest. This study significance. The results show that there is genetic variability among the mutant families, suggesting that the mutagen EMS at 1.5% is effective for generating mutants for all assessed traits. Among the characters, plant height was the most affected by the mutagen, which provided an increase in the character. For the main panicle length character, seven families showed means above the control; for main panicle weight and grain weight, four and six mutant families were observed, respectively, with a superior performance in comparison to the control.

ResumoA seleção indireta pode ser considerada uma estratégia interessante para o melhoramento de plantas, especialmente quando um caráter de fácil mensuração ou de maior herdabilidade estiver altamente correlacionado com um caráter de interesse, que apresente menor herdabilidade em populações segregantes. Os objetivos deste trabalho consistiram em obter estimativas de coeficientes de correlação fenotípica, genotípica e ambientais e avaliar os desdobramentos das correlações genotípicas em efeitos diretos e indiretos de variáveis agronômicas sobre o rendimento de grãos por meio da análise de dois ambientes de cultivo em quinze populações segregantes de trigo. Os caracteres agronômicos rendimento de grãos por planta (RG), número de grãos por espiga (NGE), peso dos grãos por espiga (PGE), massa de mil grãos (MMG), número de afilhos férteis (NAF), dias da emergência ao florescimento (DEF), dias do florescimento à maturação (DFM), ciclo total de desenvolvimento (CICLO), e acamamento (ACAM), foram avaliados em quinze populações segregantes F 4 de trigo sob dois sistemas de cultivo (com e sem encharcamento). Em todas as populações avaliadas, por meio das correlações simples, a seleção de plantas mais produtivas pode ser realizada pela seleção indireta sobre NGE, PGE e NAF. Mediante a análise de trilha foi possível identificar o efeito indireto do caráter NGE sobre RG. Assim como o efeito do PGE, do NAF, do DEF e de CICLO como causadores da formação da correlação entre outros caracteres (NGE x RG, MMG x RG, de DFM x RG, de CICLO x RG e de ACAM x RG), enfatizando que o NGE, o PGE, o NAF, o DEF e que o CICLO são os principais caracteres a serem considerados para aumentar a produtividade de grãos em trigo. Palavras-chave: Triticum aestivum L., seleção indireta, melhoramento de plantas, correlação entre caracteres AbstractIndirect selection can be considered an interesting strategy for plant breeding, especially when an easily measurable/high heritability trait is highly correlated with a target trait which has a lower heritability in segregating populations. The objective of this study was to obtain estimates of phenotypic, genotypic

Nitrogen, while favoring oat grain yields, can bring enormous losses by lodging. The aims of the study were to evaluate the productive performance of oat cultivars the susceptible and resistant to lodging under conditions of reduced, high and very high availability of nitrogen; estimate the technical and agronomic efficiency of cultivars, according to the ideal nitrogen dose, for grain yield and lodging predictability; to verify if oat cultivars with higher nutrient use efficiency for grain yield are more lodging prone, to have applicability in breeding programs. The study was conducted in 2013 and 2014 in Capão do Leão and Augusto Pestana, RS, Brazil. The experimental design was a randomized block with four replications, in a 3 x 8 factorial, being the factors evaluated the nitrogen doses and oat cultivars (resistant and susceptible to lodging). The cultivars belonging to lodging susceptible group showed higher grain yields when compared to the resistant group. FAEM Carlasul and URS Corona cultivars, from the lodging susceptible group, showed high technical and agronomic efficiency of grain yield in response to nitrogen, with high lodging at the ideal nutrient dose for grain yield. Crosses between the FAEM Carlasul and Brisasul cultivars can generate high potential genotypes regarding nitrogen use efficiency and stem resistance.

ABSTRACT:The stay-green character has been related to greater stress tolerance and yield through longer activity of the photosynthetic apparatus. Association

The chemical analysis of market-available white oat cultivars allows for their optimized use for processing, consumption, and in blocks of crosses. The purpose of this study was to evaluate the performance of white oat cultivars with regard to grain chemical content, to estimate the correlation between these traits, and to select potential REMAP markers for marker-assisted selection. Fifteen cultivars, grown in three environments, were evaluated for the contents of proteins; lipids; total, insoluble, and soluble dietary fiber; β-glucan; and carbohydrates. Eight cultivars were analysed with REMAP markers. The cultivars Brisasul and UPFA Gaudéria presented higher contents of β-glucan, while cultivars URS 21 and URS 22 had higher protein contents. For animal feed, the cultivars Barbarasul and FAPA Louise stood out with high lipid contents. Positive correlations between the contents of lipid and total dietary fiber, protein and insoluble dietary fiber, and total dietary fiber and insoluble dietary fiber were constant in different environments. Also, carbohydrate content was negatively correlated with protein, total dietary fiber, insoluble dietary fiber, and lipid content. A total of thirteen REMAP combinations were selected for variability studies regarding lipid and β-glucan contents.

Wheat is the main source of carbohydrate for humanity, being the second most-produced cereal in the world. Brazil is not self-sufficient in this crop, and the Country needs to import wheat to supply the national demand. The objective of this study was to analyze the performance of agronomic traits in wheat segregating populations in the F2 generation, and to estimate the genetic distance between the parents and the segregating populations , number of grains per ear (NGE), grain mass per ear (GME), grain yield per plant (GYP) and ear harvest index (EHI) were measured. The population 5 showed the greatest stature and population 4 showed less variability for the trait. All populations showed averages of NFT and GYP higher than the parents, indicating the presence of transgressive segregants, or presence of dominance in these traits. The grain mass per ear is the trait that contributes most to the distance between the genotypes. There was the formation of four groups by Tocher's grouping method and the population 3 is the most different to the parents, when considering all traits. Highlighted ConclusionThere is genetic variability for traits within wheat segregating populations.

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