Genetic Diversity among Elite Brazilian Soybean Cultivars with Narrow Genetic Base
Glauco Vieira Miranda, Carlos Sigueyuki Sediyama, Múcio Silva Reis and Cosme Damião Cruz
This study was carried out to assess the genetic diversity among elite soybean cultivars with narrow genetic base using prediction techniques involving data from genealogy and agronomic traits. These predictions were then compared to the agronomic diversity observed by growing the derived cross progenies. The cultivars FT-Cristalina, Doko RC, IAC-12, UFV-10 were selected based on their genetic diversity obtained from molecular markers. The six possible hybrid progenies (F1) and the four cultivars were assessed in a glass house under controlled humidity and temperature, in a completely randomized design with four replications. The genetic diversity was predicted by genealogical inference and by analysis of the groups obtained using the Mahalanobis’ generalized distance methodology based on the agronomic traits and Tocher’s optimization method. The prediction techniques and the analysis of variance of the progenies indicated the presence of genetic diversity among the cultivars with narrow genetic base. The cultivar groups formed by genealogical inference were different from those obtained by Tocher’ s optimization method. Genetic divergence evaluated by the application of prediction techniques using agronomic traits of the parents was similar to the agronomic divergence of the progenies. The prediction techniques were similar in screening only cultivars with maximum genetic divergence. It’s possible to select soybean cultivars with genetic divergence among the elite materials. The crosses among soybean cultivars that maximize the genetic divergence varied according to the prediction
technique used.