Downy Mildew Research Laboratory, University of Mysore, Mysore-6, India
*Nuclear Research Laboratory, I.A.R.I., New Delhi-12.
A line × tester analysis of combining ability revealed that both G.C.A. and S.G.A. variances are significant for downy mildew resistance. JT 328, JT 337, 71-A 97, 3503 among inbreds and 239D2A, 126D2A among male steriles are good for downy mildew resistance. Combining ability effects for downy mildew has no adverse effect on combining ability effects of agronomic characters. Non-additive gene action is predominant for downy mildew, days to flower, number of tillers, number of leaves, plant height, ear girth, number of seeds per sq. cm. and 250 grain weight.
