<b>Variability evaluation of G_o and F₁ generations of GIFT Nile tilapia strain (<em>Oreochromis niloticus</em>) by RAPD</b> - DOI: 10.4025/actascianimsci.v30i2.4708

Abstract

This study had as objective to analyze, by RAPD technique, the genetic variability and divergence of two GIFT Nile tilapia strain generations. Parameters were estimated for breeders (G_o) and offspring (F₁). The genetic variability was determined by the polymorphic loci percentage and Shannon index. The polymorphic loci percentages were 69.6% (G_o) and 60.0% (F₁). The Shannon index values were 0.367 for the G_o generation and 0.317 for F₁. Genetic divergence values, calculated using the Mantel test, were 0.213 for G_o and 0.208 for the F1 generation. The results indicated that there was a genetic variability loss from the G_o to F₁ generation. However, it is important to observe the high genetic variability found for both the G_o and F₁ generations, which is a fundamental characteristic in order to obtain gains in breeding programs. The data also indicated that the genetic status is favorable to the continuing of the GIFT improvement program in Paraná State.