ISSN 2375-091X
African Journal of Tropical Agriculture ISSN 2375-091X Vol. 7 (12), pp. 001-006, December, 2019. © International Scholars Journals
Full Length Research Paper
Assessment of the genetic diversity in five generations of a commercial broodstock line of Litopenaeus vannamei shrimp
Patrícia Domingues de Freitas and Pedro Manoel Galetti Jnr.
Departamento de Genética e Evolução, Universidade Federal de São Carlos, Caixa Postal 676, 13565-905 - São Carlos, SP, Brazil (correspondence to P.D.F.)
Accepted 12 August, 2019
Abstract
Genetic variation among and within five generations of an inbred commercial captive line of Litopenaeus vannamei and genetic distance among them were evaluated by random amplified polymorphic DNA (RAPD), using descriptive and genetic similarity analyses for dominant markers at single- and multi-populational level. One hundred individuals were analyzed and 56 polymorphic loci were identified with a set of six primers screened in a painel of 38 decamer primers tested. The values obtained for F5, F6, F 7, F 8 and F9 generations revealed a progressive increasing of genetic similarity throughout the five stocks, confirmed by Nei genetic diversity analysis, which values decreased from 0.27 to 0.22 at F5 and F9, respectively. Significant allele frequency differences were observed at most analyzed loci. Strong correlation (R2 = 0.9845) was observed between genetic similarity and generation time, and genetic similarity could reach closer to 100% at 18-19 generation of this line.
Key words: Litopenaeus vannamei, genetic diversity, genetic drift, inbreeding, RAPD.