Combining ability studies for yield components, quality characters and relative susceptibility to fruit and shoot borer in brinjal

Abstract

Six diverse brinjal lines were crossed in a diallel fashion,
excluding reciprocals to obtain fifteen cross combinations
to study combining ability for yield components, quality
characters and relative susceptibility to brinjal fruit and
shoot borer. Significant differences were observed among
genotypes for most of the characters studied. Both additive
and non-additive gene action conditioned most of the
characters while non-additive gene action was preponderant
for the control of total phenol content of fruit, seed protein
content and shoot infestation by borer. Maximum significant
gca effects in desired directions were registered by Garia for
7 characters followed by BCB-40, BCB-50 and Punjab
Sadabahar for 6 characters. However, considering the
second highest per se performance for marketable fruit yield/
plant (2.59 kg/plant) along with second lowest severity of
fruit borer infestation (18.55%) together, the parental line
BCB-40 emerged as the best followed by BCB-30, being the
highest yielder (2.69 kg/plant) and low severity of fruit borer
infestation (22.07%). The most promising cross combination
Garia × Punjab Sadabahar registering the second highest
marketable fruit yield per plant (3.74 kg / plant) exhibited the
highest significantly positive sca effects for marketable fruit
yield/ plant along with high and significantly positive sca
effect for plant height, fruit pedicel length, fruit weight, fruits
per plant and total phenol content of shoot and significantly
negative sca effect for fruit infestation by brinjal fruit and
shoot borer. Keeping in view of low narrow sense heritability
for some important characters viz., fruit weight, marketable
fruit yield per plant, total phenol content of fruit and fruit
infestation by brinjal fruit and shoot borer selection should
be based primarily on replicated family testing in F3 and
later generations. In the perspective of importance of nonadditive
genetic variance along with additive geneticvariance for the conditioning of most of the characters,
heterosis breeding to develop high yielding hybrids
possessing better fruit size, colour, quality and less
susceptibility to brinjal fruit and shoot borer may be the
best breeding strategy.