Interspecific Hybridization of Pennisetum glaucum (L) R. Br. with Wild Relatives

To widen the germplasm base for the introgression of economically important traits such as resistance to biotic and abiotic stresses from related species, crosses of cultivated pearl millet were made with pollen from four related species differing in the basic chromosome number (x=5,7,8 and 9). Embryo rescue technique was used to obtain viable progeny. Pollinations of pearl millet with Pennisetum ramosum (2n=2x=10) did not give any viable progeny. Pearl millet interspecific hybrids with P. schwelnfurthii (2n−2x−14), P. mezianum (2n=4x−32) and P. orientate (2n=2x=18) were obtained. The hybrid between P. glaucum and P. mezianum (2n=23) is the first successful report. Interspecific hybrid plants resembled their corresponding pollen parents. Southern blots of Pstl digested DNAs from interspecific hybrids and the parental species were hybridized to a full length rDNA to further confirm their hybridity. This further revealed differential amplification of two rDNA repeats among the F₁ hybrids from the same cross (P. glaucum × P. orientate).