Applications of AFLP technology in genetic and phylogenetic analysis of penaeid shrimp

Abstract

This study explores the use of amplified fragment length polymorphism (AFLP) technology in species identification and phylogenetic analysis of penaeid shrimp. AFLP fingerprinting of six Penaues species, P. monodon, P. chinensis, P. merguiensis, P. latisulcatus, P. canaliculatus and P. japonicus was compared using three sets of selective primers for PCR amplification. A total of 443 bands (size range 80–550 bp) were generated. Eight bands (1.8%) were found in all species, but only three of them (0.7%) were scored in all individuals. Species differed in the levels of genetic diversity among individuals, with 24.6% (in P. canaliculatus) to 60.8% (in P. japonicus) of the bands scored being polymorphic. Species-specific markers with potential for genetic identification of species were identified. Average genetic distances among individuals of the same species varied from 0.0023 in P. chinensis to 0.0068 in P. japonicus, while the average distances between species varied from 0.0207 to 0.0324. Phylogenetic analysis shows that the six species could be divided into two major clades. The first clade consisted of P. monodon, P. chinensis and P. merguiensis, with the latter two species more closely related. The other clade comprised P. latisulcatus, P. canaliculatus and P. japonicus. This result based on AFLP is consistent with the segregation of two distinct clades of Penaeus as previously documented by mitochondrial DNA analysis in our laboratory. This study established AFLP technology as a feasible approach in species identification and phylogenetic studies of penaeid shrimp.