This investigation !Jas carned out under fie ld condi. tio n
to study the nature of resistance for 20 Ft' B cross and
their 5 parents to common smut disease in maiBe.. Genetic
analysis suggested that the additive genetic variance
played a major role in the ezpression of this trait. The
Largest part of the total genetic variabi1.ity uae due to
additive and (additive X additive) gene action. There !Jere
significant differences for general and specific combining
ability for resistance. but the amount of general combining
abi"Zity !Jas higher than the amount of specific combining
abi"Zity. Single crOBS 104 and S.C. 105 !Jere good general
combiners for the resistance. !Jhi1.e S.C. 9. S.C. 10 and
S.C. 103 !Jere poor general combiners. The double crosses
(13:5). (33:2). (43:3). (33:5). (53:3) and (43:5) !Jere superior
for resistance. Nature of resistance !Jas assessed by
measuring the content of phenolic compounds in inoculated
and non-inoculated plants. Total. free and conjugated
pheno ls !Jere determi ned in the parents and their 20 FI' e;
P1.ants !Jere high contents of phenolic compounds sho!Jed
high resistance to the disease. |