Effects of Intraspecific Hybridization in Tilapia nilotica on Survival Under Ambient Winter Temperature in Alabama

Publisher Website
Google Scholar
Abstract
Viability under ambient winter temperatures in Alabama was assessed for Auburn University‐Egypt and Auburn University‐Ivory Coast strains of Tilapia nilotica and their F1, F2, and four backcross hybrids. Egypt strain was more viable (P= 0.05) than Ivory Coast strain. Observed mean viabilities of the F1 hybrids were intermediate between those of the parental strains. Viabilities of the reciprocal F1 hybrids were not significantly different. Viabilities of the reciprocal F2 hybrids were not significantly different. Backcross hybrids that were produced by crossing F1 hybrid females to Egypt strain had a greater observed mean viability than those that were produced by crossing F1 hybrid females to Ivory Coast strain. Average viabilities of the parental strains, F1, F2, and backcross hybrids were not significantly different. Heterosis in F1, F2, and backcross hybrids was −1.39%,−0.82%, and −2.08%, respectively. Viability under ambient winter temperatures in Alabama in T. nilotica appears to be controlled by additive rather than by dominance effects, which means that selection rather than crossbreeding is the breeding technique that should be evaluated to improve this trait in T. nilotica.

This publication has 2 references indexed in Scilit: