M.K. UPADHYAY and B. SINGH
Division of Genetics, Indian Agricultural Research Institute, New Delhi, India
With the extensive cultivation of semidwarf wheats in India a hitherto minor disease karnal bunt caused by Neovossia indica (Mitra) Mundkar assumed serious proportions. Besides causing yield losses the pathogen imparts fishy odour to the wheat flour and makes it unfit for human consumption. As confirmed sources of genetic resistance to karnal bunt are not yet available (SINGH et al. 1986), 30 strains of macaroni wheat were screened against the disease under artificial conditions of infection at Ludhiana during 1986 season. Out of these, eight strains showed immune reaction (no infection) to the desease (UPADHYAY & SINGH 1987). These eight strains were again screened against the disease under artificial infection at Ludhiana and Gurdaspur in 1987. Information on their reaction to karnal bunt, rusts (under multilocational 'hot spot' testing), flowering and thousand grain weight is given below.
The data shows that WL 711, the susceptible check variety, showed heavy infection of karnal bunt ranging from 31.9 to 58.7 percent indicating thereby that conditions were favourable for the development of the disease. RD 10 was the only strain showing immune reaction to the disease at both the locations.
RD 10 is a semidwarf macaroni wheat, medium late in maturity having amber and hard grains. The strain also possesses fair degree of resistance to rusts. Thus RD 10 appears to be an excellent source of genetic resistance to karnal bunt which can be profitably used for incorporation of resistance to the disease into Indian wheat cultivars.
The authors are grateful to Dr. L.B. GOEL, Principal Investigator (Wheat Pathology), I.A.R.I., New Delhi for getting the material screened against karnal bunt.
References
SINGH, S., L.B. GOEL & V.C. SINHA. 1986. Fungal diseases and their management. In Twenty-five years of Coordinated Wheat Research (1961 - 86). p. 127-157 (India)
UPADHYAY, M.K. & B. SINGH. 1987. Karnal bunt resistance in triticale and macaroni wheat. Annual Wheat Newsletter, Vol. 33 p. 60