Analysis on genetic variations of Erythroculter ilishaeformis （♀）×Megalobrama amblycephala （♂） Hybrids F1 by SRAP markers

Abstract:

SRAP (sequencerelated amplified polymorphism) is a new molecular marker based on Polymerase Chain Reaction. SRAP markers were used to detect genetic variations of two parents E.ilishaeformis ♀, M.amblycephala ♂ and the F₁ in this paper. 21 polymorphic primer combinations were selected from 24 pairs of primer combinations. 136 loci were amplified and 124 loci were polymorphic. Each primer combination generated 6.48 polymorphic loci, which showed comparatively high polymorphism on average. The results showed that the differentiations between parents were remarkable, and all the loci of F₁ came from their parents, and no hybridspecific locus was found. Among E.ilishaeformis ♀, M.amblycephala ♂ and F₁, the values of Nei’s genetic diversity (H) were 0.194 5, 0.172 2, 0.198 4, respectively; the values of Shannon’s information index (I) were 0.289 1, 0.254 7, 0.290 5 respectively. All the parameters indicated that hybrids F₁ showed a greater genetic diversity than their parents. Furthermore, the genetic distance between E.ilishaeformis ♀ and M.amblycephala ♂ was 0.420 6. The genetic identity between F₁ and E.ilishaeformis ♀ was 0.767 1, and the genetic identity between F₁ and M.amblycephala ♂ was 0.751 2, the differentiation was insignificant. This indicated that the hybrid F₁ has an equal heredity similarity to their parents, and this also showed that F₁ combined genetic information from both of their parents. The results also demonstrated that SRAP molecular marker technology can be applied to the hybrids tested and genetic analysis of fish breeding effectively and reliably.