Combining ability was studied in sorghum for grain yield and yield contributing characters involving seven
promising restorers on milo source of male sterility. Significant general and specific combining ability (gca & sca) variances
were observed for all the characters studied, indicating the importance of both additive and non-additive gene actions in the
expression of these traits. The gca : sca ratio was < 1 indicating predominance of non-additive gene action (dominance and
epistasis) in the expression of these traits. The gca effects for days to flowering, days to maturity, plant height, panicle
length, seed set percentage and grain yield of the line IS 28614 was high and it was considered as exceptionally a good general
combiner. The crosses IS 22720 x IS 27887, IS 23590 x IS 32439, IS 23590 x IS 4698 and IS 28614 x IS 27887 exhibited high
and significant sca and heterosis for many characters. The two combinations viz., IS 23590 x IS 32439 and IS 22720 x IS
4698 were very early to flower and can be used for breeding for earliness.