Identification of Stable Resistance to Smut in Pearl Millet

More than 1,500 accessions from a germ plasm working collection and 6,200 advanced breeding lines were screened to identify resistance to smut in pearl millet. All advanced breeding lines were susceptible, but resistance was detected in several germ plasm accessions originating from Nigeria, Senegal, Mali, Cameroon, Uganda, Lebanon, and India. To combine resistance with agronomic eliteness, crosses were made between smut-resistant lines and agronomically elite inbred lines, and pedigree selection was carried out in the segregating generations up to the F6 generation under high disease pressure. Stability of resistance was tested through a multilocational testing program, the International Pearl Millet Smut Nursery (IPMSN). Selections from six germ plasm accessions (SSC FS 252-S-4, ICI 7517-S-1, ExB 132-2-S-5-2-DM-1, ExB 46-1-2-S-2, ExB 112-1-S-1-1, and P-489-S-3) and four, newly developed, smut-resistant, agronomically elite lines (ICMPS 100-5-1, 900-9-3, 1600-2-4, and 2000-5-2) showed consistently high levels of smut resistance for 1–6 yr at six or seven locations in India and West Africa. These lines had across-location mean smut severities of less than 5% compared with 35% or more in the susceptible checks. These lines were also resistant to downy mildew in India

Identification of stable resistance to ergot in pearl millet

hen >2500 Pennisetum americanum germ plasm accessions and c. 7300 advanced breeding lines were screened against Claviceps fusiformis all the latter were highly susceptible and only very low levels of resistance were detected in a few germ plasm accessions from India, Nigeria and Uganda. Resistant lines, developed by intermating relatively less-susceptible plants and pedigree selecting for several generations under high disease pressure, were evaluated through a cooperative international multilocational testing programme, the International Pearl Millet Ergot Nursery, to determine their resistance stability. Seven inbred lines (ICMPE numbers) and 6 sib-bulk populations (ICMPES numbers) evaluated at 8-12 locations for 2-3 yr in India and West Africa showed consistently high levels of resistance. Mean ergot severities in these lines across locations ranged from <1 to 7% compared with 30-65% in the susceptible check. These lines were also resistant to smut (Tolyposporium penicillariae) and downy mildew (Sclerospora graminicola) at ICRISAT Cent., Patancher