Genetic variations among ecologically diverse species of Anurans at the level of genus based on ISSR marker

Abstract

Anurans (frogs and toads) collected from South Kanara, Udupi and North Kanara districts, Karnataka viz: Euphlyctis cyanophlyctis (an aquatic), Fejervarya rufescens (a burrowing), Duttaphrynus melanostictus (a terrestrial), Fejervarya caperata (a semi aquatic), Ramanella montana (a semi arboreal) and Polypedates maculatus (an arboreal) belonging to five genera placed under four families were compared using Inter Simple Sequence Repeat (ISSR) marker to analyze genetic variability and relationship between the investigated taxa. ISSR profile obtained exhibited 100% presence of polymorphic bands.The ISSR bands could also be categorized as high (H), moderate (M) and light (L) based on the intensity of amplification. Dendrograms were generated using similarity coefficient and relationship coefficient values based on the count of only high or high and moderate or high, moderate and light bands in each case. Analysis of the data suggests that the genetic relatedness between the taxa as exhibited in the generated dendrograms varies based on the type of amplified bands considered. The clustering pattern obtained in the case of high and moderate bands was more close to the conventional taxonomical pattern of grouping based on thephenotypic characters. The specific unique bands present in each case may be of importance as molecular markers. Observed genetic variability (presence/absence, total number, intensity of amplification and size of polymorphic bands) among taxa probably provide factors contributing partially to diverse adaptive fitness supporting varied ecological demands. However, an intensive study incorporating more representive species from each of the habitat is needed to pinpoint the importance of the unique bands as the genus/species/ecological molecular markers.