Abstract:
A field experiment was conducted with five sesame genotypes, two branched, TMV 4 and TMV 5, and three
monostemed / shybranched KS 990837, KS 990813 KS 9908513 and six cross combinations of branched x
monostemed to develop F1, F2, BC1 and BC2 populations. Six generations P1, P2, F1, F2, BC1 and BC2 were raised in
a non replicated trial to estimate the gene effects for branching and some other yield attributing characteristics.
The additive, dominance and duplicate dominance gene effects were found to be important for number of
branches per plant. Additive component was significantly positive for days to first flowering, days to maturity and
plant height in TMV 4 x KS 99037; plant height and number of branches in TMV 5 x KS 990813; days to first
flowering and days to maturity in the cross TMV 5 x KS 99153; indicating the presence of additive gene action.
Additiive x additive fixable gene interaction was also reported in different crosses. In most of the crosses, duplicate epistasis was found to be predominant when compared to complementary epistasis. Thus gene effects for a
given characteristics varied among crosses. Inheritance study using five crosses viz., TMV 4 x KS 99037, TMV 4 x
KS 990813, TMV 5 x KS 99037, TMV 5 x KS990813 and TMV 5 x KS99153, showed a monogenic inheritance of
3:1 with simple dominance recessive relationship for branching and monostem / shy branching characteristic, re spectively. The cross TMV4 x KS 99153 which showed 15:1 ratio, fitted to the expected ratio of 3:1 for branching :
shybranching respectively of the test cross progenies. This cross also showed duplicate epistasis for the number of
branches per plant in generation mean analysis.
