Interaction genotypes x sowing periods in experimental F9:2 soybean lines

Abstract

The magnitude of the interaction G x S was measured by different biometric techniques to draw inferences on improvement strategies for soybean. Twenty-five highly homozygotic (F9:2) soybean lines were evaluated in three sowing periods. The trials were set up in randomized complete blocks with three replications. The controls IAC-100, OCEPAR-4, MTBR-45, and EMGOPA-313 were used. Number of days to flowering and to maturity, grain filling period, stained seeds, weight of a hundred seeds and the grain yield (GY) were evaluated. The complex part was predominant in the partition of this interaction. In relation to the selection gain for GY a mean reduction of 10% is expected in comparison to a selection realized in period 2 only with specific selections per period, admitting a selection intensity of 40%. A reduction of 28% is expected under a selection intensity of 20%. The selection of more generalist genotypes is possible, although it leads to losses in mean terms.