Identification of resistant sources against turcicum leaf blight of maize (Zea mays L.).

Abstract

Abstract: Turcicum leaf blight (TLB) caused by Exserohilum turcicum (Pass.) Leonard and Suggs is one of the most important foliar diseases of Maize. Host-plant resistance provides sustainable disease management option. With an objective to identify new source of resistance to TLB, 237 newly developed maize inbred lines were evaluated for two consecutive years at four location in India (Dharwad, Mandya, Almora and Bajaura) under artificially created disease epiphytotics. The disease reaction of individual genotype was rated on 1-9 scale. On the basis of pooled mean over locations, 41 inbred lines were found resistant (disease incidence <3.0), 181 inbred lines were moderately resistant (disease incidence 3.1-5.0) and 15 inbred lines were moderately susceptible (disease incidence 5.1-7.0). Out of 41 inbred lines, 33 lines viz. IMLSB-57-2, IMLSB-119-1, IMLSB-143-1, IMLSB-205-1, IMLSB-244- 1, IMLSB-246-2, IMLSB-266-2, IMLSB-306-1, IMLSB- 317-1, IMLSB-334B-1, IMLSB-343-1, IMLSB-343-2, IMLSB-380-1, IMLSB-428-2, IMLSB-446-2, IMLSB-475- 2, IMLSB-568-2, IMLSB-748-1, IMLSB-801-2, IMLSB- 807-1, IMLSB-825-2, IMLSB-955-1, IMLSB-956-2, IMLSB-975-2, IMLSB-976-2, IMLSB-1018-1, IMLSB- 1041-4-1, IMLSB-1043-1-1, IMLSB-1299-1, IMLSB- 1299-7, IMLSB-1381, IMLSB-2034, IMLSB-2136 were resistant at three locations and across location (mean basis), whereas 8 inbred lines IMLSB-282-2, IMLSB-310-2, IMLSB-1046-3-1, IMLSB-1047-1-1, IMLSB-1376, IMLSB-2051, IMLSB-2119, IMLSB-2166 were resistant at two locations and across mean basis. These 41 maize inbred lines, possessing resistance to turcicum leaf blight can be used successfully in developing promising hybrids.