Analysis of intraspecific heterosis, heritability and genetic correlation of growth traits of Macrobrachium rosenbergii

Abstract:

The germplasm resources of M. rosenbergii are declining in China. To solve this problem, we used 5 strains (A,B,C,D,E) as parents to make complete diallel cross and built 25 mating combinations, whose intraspecific heterosis and genetic correlations of growth traits (body length, carapace width, the first abdominal segment width, the first abdominal segment height and body weight) were analyzed at 90 dph, respectively. The results indicated that the growth traits of all hybrid combinations were better than those of self-combination except D×C. The heterosis was observed in all hybrid combinations, the hybrid combinations of A×E has the greatest heterosis. It can increase the body length by 17.22%, and can increase the weight gain by 71.64%. The heritability was 0.549, 0.548, 0.527, 0.516, 0.580 for body length, carapace width, the first abdominal segment width, the first abdominal segment height and body weight, respectively. The genetic correlation and phenotypic correlation between body length and body weight was the highest (0.752 2 and 0.98), while the genetic correlation between carapace width and first abdomere segment height was the lowest (0.667 5), and the phenotypic correlation between body length and the first abdominal segment height was the lowest (0.924 0). The results would provide theoretic basis for further fast growth selective breeding and hybridization of M. rosenbergii.