Selection index and molecular markers in reciprocal recurrent selection in maize

Abstract

Reciprocal recurrent selection among full-sib families is one of the outstanding methodologies of maizeimprovement, since gains are possible in the per se and/or in cross populations. Here the selection index proposed by Smithand Hazel was used in the cited methodology; besides, an additional phase involving RAPD markers was introduced topreserve the genetic variability of the selected genotypes and identify contaminants before their recombination. Multivariatetechniques of grouping and discriminant analyses were used for this purpose, to assure the continuance of the improvementprogram and amplify the genetic distance between the populations Cimmyt and Piranão, which were used for an intervarietalhybrid. The molecular technique proved useful to identify contaminants and helpful in the choice of the genotypes to berecombined to maximize heterosis among populations. The technique can be included in recurrent selection programs, mainlythose that target the development of hybrids.

Keywords

• Zea mays
• recurrent selection
• selection index
• molecular markers
• discriminant analysis.