Tropical and Subtropical Agroecosystems (Dec 2012)
PUTATIVE LOCI ASSOCIATED TO POLYEMBRYONY IN MAIZE POPULATIONS
Abstract
Polyembryony (PE) is a reproductive phenomenon that produces more than one plant per seed in maize and other species. The objective of this study was to identify polymorphic DNA bands associated to the genetic expression of this trait using AFLPs. The genetic materials used in this study were 19 Polyembryonic experimental maize lines from two populations, identified as BAP (dwarf, high PE frequency genotypes) and NAP (normal height, high PE frequency) and 16 non-polyembryonic commercial genotypes (NPE). Results showed that the PE seeds had a germination rate of 89.47 %, where 28.23 % were single seedlings and 71.76 % were polyembryonic seedlings. Most of the polyembryonic seeds produced double plants although some triple plants cases were also observed. In addition, twenty nine putative loci were identified associated to the maize polyembryony; this association may be related to the differential origins of the maize populations. In addition, the rate of genetic diversity between the groups PE and NPE was estimated at the locus level using the Shannon index, getting a range of polymorphism from 29% to 53%, this could be related to the origin of the tested samples and their phenotypic and genotypic traits. These results suggest that the polymorphic bands may be related to the expression of genes linked to polyembryony in maize.