Maize is the most im.portant crop in Venezuela and 95% of cultivated area is hybrid seed. Double-cross hybrids have been rapidly adopted and have contributed to sustained yield gains over 30 years. In the last decade, however, yield improvement has diminished considerably. Maize breeders have suggested the development of single-cross hybrids to achieve maximum expression of heterosis and overcome yield decay (Bejarano 2000). A hybrid oriented breeding program requires integrated improvement strategies that depend on combining ability and improvement of heterotic patterns (Vasal et al. 1997). Reciprocal recurrent selection methods are designed to improve the interpopulation cross (hybrid) and, therefore, facilitate better integration between population and hybrid improvement. Modified full-sib reciprocal recurrent selection (MFSRS) (Eberhart et al. 1995) was initiated in P49C17 and NB12 to improve performance of the populations themselves and to enhance the level of heterosis of the population cross. Objectives of our study were: (1) to estimate genetic variances and heritabilities of full-sib families for grain yield and other agronomic traits; (2) to calculate expected genetic gains; and (3) to select the 10% superior full-sib families.

Global Maize Program

English

0309|AGRIS 0301|AL-Maize Program

Juan Carlos Mendieta

INT3035

CIMMYT Publications Collection