Molecular characterization of vernalization and photoperiod genes in wheat varieties from different agro-climatic zones of India

Ninety-nine wheat cultivars from six different agro-climatic zones of India were analyzed for the Vrn-1, Vrn-2, Vrn-B3, Vrn-4 and Ppd-D1 composition with DNA sequenced based allele specific or linked markers for the above-mentioned genes. A majority of the germplasm carried the dominant Vrn-A1a allele alone or in combination with Vrn-B1 and Vrn-D1. The three dominant genes were cumulatively present in 30 cultivars among all the zones, whereas double dominant combination, Vrn- A1/Vrn-B1 was identified in 18 cultivars, Vrn-A1/Vrn-D1 in 6 cvs and Vrn-B1/Vrn-D1 in 16 cvs. The combination of the dominant alleles of all three genes was most frequent in cvs of Northern Western Plains Zone. Northern Hill Zone had vrn-B1 and vrn-D1 alleles in higher proportions compared to the dominant alleles Vrn-B1 and Vrn-D1 indicating successful spring/winter wheat cross breeding. All of the cvs had the recessive Vrn-B3 allele. Most of the cvs had photoperiod insensitive allele in all the zones and only 9% cvs possessed the photoperiod sensitive allele (b) of the Ppd-D1 gene. This information will be useful in selecting parental lines for crossing to maximize diversity at these loci and for future molecular marker assisted breeding for cultivar improvement.