Adaptability and stability of soybean in terms of oil and protein content

The objective of this study was to evaluate the influence of genotype x environment interaction on the seed oiland protein content in soybean genotypes (Glycine max L. Merrill). Fifteen soybean genotypes were evaluated. The experimentswere conducted in the growing seasons 2004/05, 2005/06 and 2006/07 in Viçosa and Frutal, Minas Gerais (MG), andPindorama, São Paulo (SP), respectively, with different planting dates and soil types, in a total of 13 environments. Theevaluation was based on the methods of Eberhart and Russell and Extended Centroid. The results showed that genotype UFV18 is desirable in soybean breeding programs designed to increase the values of the two traits evaluated. The results ofgenotype PTN-Bio were different for each trait. Moreover, it was noted that the Extended Centroid method is more conservativethan the methodology of Eberhart and Russell in the classification of genotypes.