Adaptabilidade de genótipos de soja em ensaios multiambientes para o cerrado do Piauí

Abstract

The cultivation of soybean has significantly grown in the cerrado region of Piaui, Brazil. However, this region usually presents Indian summer, which makes it essential for the producer to grow adapted cultivars. It is necessary to perform trials in different environments to identify genotypes with wide adaptability and stability. The objective of this work was to evaluate the adaptability of soybean genotypes and the interrelationship of environments in the cerrado of Piaui. In the first year of evaluation, two different trials were performed in five locations: in Monte Alegre do Piauí, at Fazenda Celeiro; in Baixa Grande do Ribeiro, at the Aliança and Ypê farms; and in Uruçuí, at the Canel and Emílio farms. In the second year, the best genotypes of the first year were sown at the same farms. The experimental design used was in randomized blocks, with three replicates. The following characteristics were evaluated: grain yield (GY), weight of 100 seeds (WHG), and plant height (H). Analysis of variance was performed using the GGEBiplot method. There was no water deficit and the agricultural years presented good productivity in both years. The variation between environments was significant for all characteristics. In general, the genotypes showed WHG above 15 g and H superior to 60 cm. It would be initially possible to reduce the number of sites for the years and places considered, given that they are not discriminating the genotypes satisfactorily. However, there was no difference for grain yield in two environments. A small number of environments can make selection difficult depending on the agricultural year, especially if there are harvests with intense Indian summer seasons, in which the productive performances tend to reduce significantly. Additionally, there was no consistency in the interrelationship of the environments. In conclusion, it was possible to identify genotypes that associated high productivity and phenotypic stability for GY.