Development of a Biofuel Pearl Millet a/B Pair Via Combined Phentoypic and Marker Assisted Backcrossing.

Pearl millet (Pennisetum glaucum [L.] R. Br.) by Napiergrass (Pennisetum purpureum Schumach.) interspecific hybrids have significant potential as biofuel feedstocks; however, their utility is currently limited by the availability of only grain-type cms pearl millet A/B pairs. Towards development of biofuel-type cms pearl millet A/B pairs, a high-biomass, profuse basal tillering, late flowering pearl millet genotype (PEGL09TX04) was utilized as a pollinator in controlled hybridizations with the cms pearl millet line PI-508273.  Recovery of the recurrent parent’s biofuel ideotype was initiated by backcrossing of male-sterile hybrids to PEGL09TX04. A combined phenotypic and marker-assisted introgression strategy was utilized, in which the F₁ and each backcross generation was screened for both biofuel traits (tiller number, late flowering, etc.) and presence of recurrent parent-specific EST-SSRs. Subsequent characterization of male-sterility allowed parallel advancement of both A-lines and B-lines.  Progress to date will be presented.