-The objective of this work was to evaluate the association between estimates of adaptability, stability, and productivity in soybean (Glycine max), and to estimate the repeatability coefficient of these associations between years. A total of 22 genotypes were evaluated in 27 environments in the 2012/2013 crop season and in 19 environments in 2013/2014. In the next crop seasons, 28 genotypes were evaluated in 26 environments, in 2014/2015, and in 25 environments in 2015/2016, totalizing 97 trials. Fourteen methods were evaluated; Spearman correlation coefficients were obtained for the parameters of stability, adaptability, and productivity; and the repeatability coefficients, as well as the minimum number of required environments for a coefficient of determination of 80 and 90%, were

No abstract

The aim of this study was to evaluate the experimental precision of different methods of statistical analysis for trials with large numbers of soybean genotypes, and their relationship with the number of replicates. Soybean yield data (nine trials; 324 genotypes; 46 cultivars; 278 lines; agricultural harvest of 2014/15) were used. Two of these trials were performed at the same location, side by side, forming a trial with six replicates. Each trial was analyzed by the randomized complete block, triple lattice design, and use of the Papadakis method. The selective accuracy, least significant difference, and Fasoulas differentiation index were estimated, and model assumptions were tested. The resampling method was used to study the influence of the number of replicates, by varying the number of blocks and estimating the precision measurements. The experimental precision indicators of the Papadakis method are more favorable as compared to the randomized complete block design and triple lattice. To obtain selective accuracy above the high experimental precision range in trials with 324 soybean genotypes, two repetitions can be used, and data can be analyzed using the randomized complete block design or Papadakis method.

Soybean is an important oil and protein source for human and animal food, as well as being used in the production of biofuel. Brazilian soybean is known for its quality, especially with regard to its high protein content. This work aimed to present a screening of Brazilian soybean cropped at different locations, to assess the composition of seed with regard to the protein, oil and fatty acid contents. We screened 46 cultivars, which represent more than 50% of the soybean cultivars produced in the South-Center region of Brazil in recent years, analyzed under six environments. In order to conduct the analysis, a grain sample was used to determine seed protein, oil and fatty acid contents, which was accomplished using near infrared spectroscopy (NIR). All the traits presented a genotype x environment interaction (GEI) (p<0.01). A mean oil content of 20.35% was identified for all the evaluated cultivars. This was superior to that obtained in other countries. The mean protein content was 40.20%, which was expected for the Brazilian soybean. This higher oil content is doubly favorable in Brazilian soybean: firstly, for its use as cooking oil and biofuel; secondly, for the production of high protein soybean meal, once all the oil is removed. The cultivars which presented the highest oil contents were also stable across the evaluated environments. On the other hand, the genotypes with the highest protein content presented low stability across the environments. Regarding the fatty acid composition, Brazilian soybean stands out for its low linoleic acid content, which gives a high oxidative stability to the resulting oil and biofuel. Trait associations were dependent on the location, thus breeders can select plants for specific traits at different locations. Brazilian cultivars present interesting characteristics for use in human and animal food products, and for biofuel production.

The present study aimed to evaluate the associations between agronomic and bread-making quality traits in wheat under different growing environments. Nineteen Brazilian wheat cultivars were evaluated at six locations (Cascavel-PR, Castro-PR, Guarapuava-PR, Palotina-PR, Abelardo Luz-SC, and Não-Me-Toque-RS) during five years (2007 to 2011). The direction and magnitude of the associations between agronomic and bread-making quality traits were strongly dependent on the test location and year of evaluation. This study discusses the implications of choosing test locations on bread-making quality traits and for breeding purposes, with emphasis on indirect selection.