Inheritance and molecular mapping of gene controlling cream grain color in pearl millet [Pennisetum glaucum (L.) R. Br.]

Grain color in pearl millet is a combination of the color and thickness of the pericarp, particularly the mesocarp, and the color and vitreosity of the endosperm. Pearl millet has a thin pericarp which allows endosperm color and texture to appear through pericarp. Segregation analysis involving F1, F2, and BC1 populations from six crosses WGI 100 x ICMB 13222, HFeIT 17/2 x PPMI 1229, ICMB 13222 x PPMI 1229, HFeIT 17/2 x WGI 100, ICFD 14-R-61 x WGI 100 and ICFD 14-R-61 x PPMI 1229 revealed that single pair of major genes governs cream grain color in pearl millet. Cream grain color was found to be dominant over grey grain color. Two DNA pools were established from the homozygote cream and grey grain color plants for bulked segregant analysis. Among the 313 pairs of microsatellite primers used in the present study, three markers showed polymorphism in DNA pools, parents, F1and F2 populations. Molecular mapping and validation revealed that the gene controlling cream grain color is present on linkage group 2 and flanked by markers Xpsmp 2089 and Xipes 0218 at a distance of approximately 16.9 cM and 17.9 cM, respectively. This work is the first report on the molecular mapping of the gene that controls the color of cream grains in pearl millet.