Genetic Variation of Three Populations of Indian Frog ( Hoplobatrachus tigerinus ) Revealed by Allozyme Marker

摘要

The Indian bullfrog, Hoplobatrachus tigerinus plays a significant role in maintaining the natural balance in the ecosystems. It plays an important role in controlling the various agricultural pests because of its omnivorous feeding habit. The aim of the present study is to know the genetic variation of H. tigerinus in three natural habitats. Samples collected from three districts of Bangladesh were analyzed with five enzymes (MDH, LDH, GPI, PGM and EST) in CA 6.1 buffer system for their genetic variation . Four polymorphic loci (Mdh-1, Est-1, Gpi-1 and Pgm) were interpretable in muscle with starch gel electrophoresis. Among the 5 presumptive loci, the mean proportion of polymorphic loci was observed 80, 80 and 60% in Rangpur, Khulna and Mymensingh populations, respectively. The highest mean number of allele per locus and mean proportion of heterozygous loci per individual were observed in the Rangpur population. The average observed heterozygosity (Ho) was 0.163 and expected heterozygosity (He) was 0.469. In pair-wise analysis, comparatively higher Nm value (5.507) was estimated between the Rangpur and Khulna populations corresponding lower level of FST value (0.043). The UPGMA dendrogram showed two clusters among the three Indian bullfrog populations. Rangpur and Khulna populations formed one cluster while Mymensingh population formed another cluster. The Mymensingh population separated from Rangpur and Khulna by a genetic distance of 0.177 whereas, the Khulna population is different from the Rangpur population by the genetic distance of 0.052. The results suggested that the considerable genetic variation is maintained among the natural H. tigerinus populations.