Gujarat Agricuhural University, Sardar Krushinagar - 385 506, India
* Present address: Main Dry Farming Research Station, G.A.U., Targhadia - 360 003, India
Combining ability analysis was undertaken using hne x tester mating design involving four females and 28 males under four environments for earliness and its related traits in castor. The analysis of variance indicated preponderance of non-additive type of gene action in the expression of all the four traits. Parents RCG 5, EC 103745, Bhagya for early flowering and maturity; JI 77, SH 16, Hazarl 1 for dwarf plant height and SH 21, SH 16, RCG 5 for lesser number of nodes upto main spike were best general combiners. The Cross SKP 93 x VI 9 for days to flowering and cays to maturity; VP 1 x SA 2 for plant height and SKP 93 x SKI 12 for number of nodes upto main spike was the best specific combinations to exploit non-fixilble components.
