Analysis of diallel cross for some reproductive traits in ornamental fish (Puntius tetrazona)

The best method of fish breeding is the isolation of pure lines having high-producing hybrids. The decline in heterosis (DIH) resulted from inbreeding, maternal effects, general combining ability (GCA) and specific combining ability (SCA) on reproductive traits (e.g., egg production, number of hatched egg, and hatchability of pure lines and crosses) of Tiger, Green, and Albino Barbie hybrids were cross-checked using a full diallel cross design. The results showed that the rate of heterosis was negative for all traits and heterozygous offspring were not superior to their counterparts in pure lines. The highest DIH was observed in egg production while the least DIH was seen in hatchability. When the Albino line was used as maternal line, the performance of hybrids was higher than other crossing programs because of highly positive maternal effects in Albino line. Analysis of GCA represents the additive genetic superiority for egg production in Tiger line rather than other genetic lines and this breed line possess high capacity for transferring the breeding values of spawning power to their offspring. In addition, the highest rate of SCA for egg production, number of hatched egg, and hatchability was attributed to the crosses of male Tiger × female Green, male Tiger × female Albino, and male Albino × female Green, respectively.