Genetic Control of the Physiological Quality in Soybean Seeds.

The selection of soybean cultivars with high seed physiological quality is important task during breeding program in Brazil due to the adverse conditions of temperature and relative humidity that takes place in some regions of Brazil.Thus, is important to know the genetic control for the seed physiological quality during selection in breeding programs. Therefore, this work had the objective to study the genetic control for seed physiological quality in soybean. F₁ hybrid seeds were obtained using three cultivars, previously selected, from seeds with high physiological quality and three with low physiological quality, including the reciprocal, using the system of partial diallel crosses plus the parental lines. Soybean was manually harvested at the stage R8 and the seed were dried in the shade until water content of about 12%. To increase the quantity of seeds, the generation F₁ was multiplied and generation F₂ was obtained. The sowing and harvesting conditions were the same as the previous season. Seed physiological quality was evaluated by means of accelerated aging test at days 5 and 11 and the germination speed index. The effects of general capacity and specific combination as well as the reciprocal effects were significant for physiological quality of the seeds, which indicates that both gene additives effects as well as non-additives were involved in the control of this characteristics and that the effect can be explained by the maternal effect. From the genetic variation observed is possible to develop genotypes with high physiological quality through crossings targeted.