Genotype by environment interactions, heritabilities and genetic correlations for productive traits of Haliotis rufescens

Abalones are one of the most important mollusks in aquaculture due to their commercial value in international markets, especially in Asia; as such there are several efforts to develop abalone breeding programs in different countries. In this work we addressed a critical aspect for a selective breeding program, which is to know whether responses of productive traits are similar in different environments. Considering that the magnitude of the genotype by environment interaction (GEI) together with heritability (h2) accounts for this aspect, we estimated these genetic quantitative parameters for growth traits (total mass, shell length and width) in two cohorts of the red abalone, Haliotis rufescens, cultivated throughout Chile. Results indicated that the application of selection by the shell length at age of harvest has the greatest potential for improving the production of H. rufescens. These improvements are practical (ease and accuracy in measurement), have indirect effects on the objective trait of selection (weight), and consist of a trait that is not significantly affected by genotype-environment interactions. In addition, the results obtained suggest that a single selective breeding program would be sufficient for the red abalone industry in Chile, as the response to selection of traits associated with growth would be similar in different environments. Red abalone is naturally distributed in California and Baja California coasts, and this information can be especially useful in planning breeding programs also in the west coast of USA and México.