Application of microsatellite markers to evaluate the heterozygosity from the popcorn composite CMS-43 (Zea mays L.) during eight cycles of selection

Abstract

With 5 tables Maize breeders in Brazil developed the popcorn cultivar BRS Angela after eight cycles of recurrent selection using the composite CMS-43. We extracted the genomic DNA from the leaves of the BRS Angela, and we used 20 microsatellite markers to assess both the genetic distance and variability of this variety along the eight cycles (C0, CI, CII, CIII, CIV, CV, CVIA and CVIB) of the composite CMS-43. Sixty-nine alleles were detected in the popcorn cultivar BRS Angela with an average of 3.45 alleles per polymorphic locus. There was significant effect (P≤0.01) only for D allele at the Umc 2343 locus and for the alleles A and B at the Umc 2226 locus. There was no tendency in the changes in the allele frequencies, presumably, because of selection for grain yield and popping expansion. The observed heterozygosity along these cycles ranged from 38.67% (CIII) to 26.67% (CVIB). These values indicate the presence of heterozygosity in the breeding cycles, and therefore, the 'BRS Angela' can participate in new cycles of recurrent selection. © 2012 Blackwell Verlag GmbH.