New sources of resistance to grain mold in converted Zerazera sorghum uri icon

abstract

  • Zerazera sorghums have been extensively used in sorghum improvement programmes because of their agronomic desirability, superior grain quality and disease tolerance. Some 347 selections, derived from 12 accessions, were screened for resistance to the most predominantly occurring grain mould fungi, Fusarium moniliforme (Gibberella fujikuroi), F. pallidoroseum and Curvularia lunata (Cochliobolus lunatus). Seeds were dipped in a spore suspension of the fungal isolates and evaluated for mould severity after 5 days in a humid chamber, on a scale of 1-9 (1 = no mould, 9 = greater than 75% surface area covered by mould). The 43 most resistant selections (mean mould rating of 2.2-3.5) were further evaluated in a field grain mould nursery in Andhra Pradesh during 1993 and 1994, and under natural conditions in Tamil Nadu and Karnataka. For each selection, 10 panicles were tagged and evaluated for resistance at maturity, 14 days post maturity and after threshing. The mean mould rating of most of the 43 selections across all locations was less than or equal to 4 (less than or equal to 20% coverage). Eight accessions, (two each of IS 18758C-618, IS 1875C-710 and IS 30469C-140 and one selection each of IS 30469C-1187 and IS 30469C-1508T) were selected as promising, showing consistently high levels of mould resistance (<3) and also high levels of resistance to anthracnose (Colletotrichum graminicola) and leaf blight (Exserohilum turcicum (Setosphaeria turcica)) (data not reported) at all the locations

publication date

  • 2002