Morphological and genetic diversity levels of Penaeus monodon (Fabricius, 1798) populations in three coastal regions of Sri Lanka

Abstract

Morphological and genetic variations of three Penaeus monodon populations in Sri Lanka were determined using data from truss network method and partial amplification of mitochondrial control (mtC) gene region respectively. Total of
37 morphometric characters were collected from 178 individuals representing three populations (eastern, western and southern) and subjected to principal component analyses (PCA) to determine the morphological variation among three populations. Two principal components (PC) derived from PCA analysis with the accumulated variance for the two PC represented 75% of the total. The plot against first and the second principal components scores revealed great morphological similarity among three populations. For genetic analysis, a total of 600 bp DNA fragment was amplified from mtC gene region and 26 haplotypes were produced for three populations from the total of 63 samples examined. Among three populations, mean haplotype diversity (h) ranged from 0.35 (southern) to 0.92 (eastern) and nucleotide diversity (Ï€) ranged from 0.005 (southern) to 0.025 (western). Analysis of molecular variance (AMOVA) indicated within population variation as 78.89% and among population variation as 21.11% indicating high intra-population diversity. The overall Fst value indicated significant genetic structure among three populations (Fst = 0.2111, p < 0.05). Genetic diversity levels of Sri Lankan
P. monodon populations were compared with published data for this species from other geographic locations.