GENETIC STOCK CHARACTERIZATION OF KIDDI SHRIMP Parapenaeopsis stylifera (H. MILNE EDWARDS, 1837) USING MICROSATELLITE MARKERS

Parapenaeopsis stylifera (H. Milne Edwards, 1837), commonly known as kiddi shrimp, is an economically important Penaeid shrimps in India comprising ~25% of total Penaeids. However, there is lack of knowledge on population genetic structure of this species. This would lead to loss of genetic diversity on account of overexploitation of stocks.  The present study was carried out to characterize the genetic stocks structure of Parapenaeospis stylifera using microsatellite markers. A total of 350 individuals were collected from five landing centers representing east and west coast of India (East coast: Tamil Nadu & Andhra Pradesh; West Coast: Kerala, Goa, Maharashtra & Gujarat). Eleven microsatellite markers representing di (9 no.) and tri (2 no.) repeats were used to characterize the genetic stocks of P. stylifera. Moderate allelic richness was observed with a range of 10 to 24 alleles per locus. The mean observed (Ho) and expected (He) heterozygosity values ranged from 0.641 to 0.692 and 0.710 to 0.743, respectively. Five loci showed deviation from Hardy-Weinberg equilibrium and no significant linkage disequilibrium between loci pairs was detected. Genetic differentiation value (F_ST=0.003) was less between the populations of Gujarat, Goa & Kerala (West coast). Similarly, less genetic differentiation was observed between Tamil Nadu-Andhra Pradesh (East coast) populations (F_ST = 0.002). However, moderate genetic differentiation was observed between East and West coast populations with a F_ST value of 0.029. Structure and Principal Co-ordinate analyses showed population admixture with moderate genetic differentiation between the coasts. The geographical isolation and oceanographic features between the east and west coast of India could have caused transient reproductive isolation and subsequent genetic divergence between the populations of P. stylifera. The findings of the present study showed that populations from east and west coast of India are two distinct management units (MUs) and requires separate monitoring and management practices.