DEVELOPMENT OF MOLECULAR MARKERS FOR IDENTIFICATION OF HYBRIDS OF Tor putitora AND Tor khudree

Species of Tor (Mahseer) are being declined due to habitat destruction, anthropogenic factors and climate change. To conserve these species, breeding technology has been standardized for Tor putitora and Tor khudree. However, due to ambiguity in morphological characters, inadvertent crossing could be possible between Tor putitora and Tor khudree. Further, the progeny of hybrid cross would be viable due to similar chromosome number. These hybrids would compete with native fishes and cause genetic introgression If released into natural water bodies. A screening method with less invasive approach would assist in managing pure stocks of species of Tor. With this background, the present study was carried out to develop molecular markers for selected species of Tor and its hybrid species. Pure samples of Tor putitora and Tor khudree were collected from their type locality and their species identify was confirmed by mitochondrial cytochrome c oxidase subunit I gene and nuclear 18S ribosomal RNA gene. Hybrids were generated by reciprocal crossing between Tor putitora X Tor khudree. Nuclear 18S rRNA was amplified and sequenced to develop markers for detecting pure and hybrid species. The developed markers displayed two amplicons (700 and 500 bp) in hybrids and single amplicon in pure species (700 bp: Tor khudree; 500 bp: Tor putitora) (Fig.1). This marker has application in monitoring natural stocks and detecting hybrid species.