Aurilene Santos Oliveira
Abstract:
With the possibility of planting corn in two seasons (normal and late crops) the Brazil has increased the total corn production, but it is necessary to develop new hybrids and varieties aiming to increase productivity in both planting dates, to attend increasing demand for this commodity. The objectives of the present work were directed for the study the genetic variability, evaluate the yield potential and estimate inbreeding depression in three semiexotic populations of maize, for purposes of recurrent selection. The field evaluation was in two experiments: Jataí (GO) and Anhembi (SP). The first experiment was represented by half-sib families, which were evaluated in randomized complete blocks with three replications with plots of 4m (0.90 m spacing) with 20 plants. The second experiment included half-sib and S1 families in two replications with plots of 3m (0,90 m spacing) with 15 plants. The following primary characters were evaluated: AP - plant height (cm), AE - ear height (cm), DE – ear diameter (cm), EC - ear length (cm), NP - number of plants, NE – ear of number, PE - ear weight (g parcela-1), PG – total grain weight (g parcela-1), PE4 - four ear weight, PG4 - four ear grain weight, NR -tassel branch number, CP - tassel length (cm), AD - evaluation of foliar disease and ACE - evaluation of corn stunt complex. The semiexótic populations CRE had an excellent pattern of genetic variability and a good productive potential, presenting an average yield of 70% compared to checks. Within the three populations it was observed differences of families in relation to resistance to corn stunt, indicating that selection for this trait can fairly effective.
