Inheritance of Complete Resistance to Pearl Millet Downy Mildew

Abstract

Inheritance of downy mildew (Sclerospora graminicola) resistance in pearl millet (Pennisetum glaucum) was studied in a cross involving DMRP (downy mildew resistant Pennisetum) 292 and DMSP (downy mildew susceptible Pennisetum) 23. DMRP 292, derived from IP 18292, and DMSP 23, derived from Tift 23DB, were made homozygous for downy mildew resistance-susceptibility by three generations of single plant selection followinginoculations with homogenized sporangial population of S. graminicola from the ICRISAT Asia Center. Potted seedlings of parental lines, F 1 , F 2 , and BC progenies were evaluated for their reactions to downy mildew following inoculation. The results show that complete resistance to downy mildew in DMRP 292 is controlled by a single dominant gene. Because of the simple mode of inheritance, resistance utilization from DMRP 292 is simple and straightforward. We designate this gene as Rsg 1 .