Identification of Stable Resistance to Smut in Pearl Millet. R. P. Thakur, Pearl Millet Improvement Program, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru P.O., Andhra Pradesh, 502 324, India. K. V. Subba Rao, and R. J. Williams, Pearl Millet Improvement Program, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru P.O., Andhra Pradesh, 502 324, India; S. C. Gupta, ICRISAT-CNRA, Bambey, Senegal; D. P. Thakur, Haryana Agricultural University, Hisar, 125 004, India; S. D. Nafade, Millet Research Station, Gujarat Agricultural University, Jamnagar, 361 006, India; N. V. Sundaram, ICRISAT, Institute of Agricultural Research, ABU, Zaria, Nigeria; J. A. Frowd, ICRISAT, Ouagadougou, Burkina Faso; and J. E. Guthrie, ICRISAT Sahelian Center, Niamey, Niger. Plant Dis. 70:38-41. Accepted for publication 6 June 1985. Copyright 1986 The American Phytopathological Society. DOI: 10.1094/PD-70-38.

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.