Clarias batrachus (Linn.1758) population is lacking genetic diversity in India

Abstract

Genetic similarity and diversity of catfish Clarias batrachus (Linn.1758) populations collected from three regions of Indian riverine system were examined using randomly amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR). Out of 22 random primers tested, six primers produced 462 RAPD bands ranging from 105 to 128 polymorphic bands per primer in size between 100 and 1,200 bp. The polymorphic bands in these populations ranged from 26.5 to 30.5. Polymorphic bands within populations ranged from 25 to 35.7%. The degree of similarity within Hussainabad population varied from 0.125 to 0.842 based on average level of band sharing (BS) values. The level of band sharing values within the catfish populations were 0.26 +/- 0.021 for Banaras, 0.60 +/- 0.033 for Bhubaneshwar and 0.377 +/- 0.058 for Hussainabad respectively. The results from the present study indicate that there is great degree of genetic similarity between Bhubaneshwar and Hussainabad populations where as Banaras catfish population is distinct. It may appear that Bhubaneshwar and Hussainabad are geographically connected by rivers and most of the major catfish hatcheries are located in this region, therefore the individuals from these populations are get reared in the same environmental conditions, migration or by inbreeding during several generations may be possible. This may be the reason that catfish population is lacking genetic diversity in major riverine system of India. In nearer future, the lack in genetic diversity can lead to inbreeding which can be resulted in poor growth and disease susceptibility, Bhubaneshwar and Hussainabad catfish population may have this problem.

GENETIC VARIABILITY IN CULTURED AND WILD POPULATIONS OF Clarias gariepinus (Osteichthys: Clariidae) USING RANDOM AMPLIFIED POLYMORPHIC DNA (RAPD) MARKER

“…High quality bands with good reproducibility generated Garg et al (2010) who reported 172 to 1677bp in C. batrachus. Khedkar et al (2010) found good quality bands in the range of 100 to 1200bp in Clarias batrachus. The higher value in band range in this study might be attributed to species differences and source of samples.…”

Comparison of reproductive performance of Clarias batrachus (Linnaeus, 1758) collected from three Indian rivers

“…Magur breeds once in a year during June to August in the natural environment. However, population of this species has been reduced drastically during recent years due to overfishing, habitat alterations and indiscriminate use of pesticides in preferred natural breeding grounds such as paddy fields and wetlands (Goswami, 2007;Khedkar et al, 2010). This species is classified under threatened category (Argungu et al, 2013), warranting the need for conservation and sustainable management.…”

Response of a freshwater air-breathing fish, Clarias batrachus to salinity stress: an experimental case for their farming in brackishwater areas in Andaman, India

“…Clarias batrachus is an omnivore fish having broad feeding habits at different life stages (Hora and Pillay 1962). However, in recent times, the magur population has decreased at an alarming rate due to high fishing pressure as well as habitat destruction (Sahoo et al 2010;Khedkar et al 2010) and has become a vulnerable species (CAMP 1998).…”