Such studies are highly informative for the management of small group in ex-situ collection, cultivars identity, breed or clonal identification and for paternity testing. The genetic variability within population is extremely useful to gather the information on individual identity, breeding pattern, degree of relatedness and distribution of genetic variation among them. Variation at the population level can provide an idea about how many different genetic classes are present and the genetic similarity among them, how much diversity is present in those classes and their evolutionary relationship with wild relatives. Genetic variation at species level helps to identify the taxonomic units and to determine the species distinctiveness that can provide essential information for conservation, systematic, ecological and evolutionary studies (Schieverwater et al., 1997). Therefore, detection of genetic variation at species and population level is of crucial importance for sustainable aquaculture practices. Individuals with high level of genetic variation have great prospect in aquaculture in terms of higher growth rate, development, stress and diseases resistance (Carvalho, 1993). The knowledge of genetic background of a species and its population structure is essential for success in breeding, management and conservation programs in fisheries. A polymerase chain reaction based DNA typing requires no prior knowledge of target DNA sequence, termed RAPD-PCR (for random amplified polymorphic DNA) is found to generate genetic diversity assessment in fishes. To identify molecular genetic markers, various techniques are used to detect polymorphisms in the population. to the total World Aquaculture production in 2005 (FAO, 2007). However, as a single species, Catla catla contributed 1,235,992 mt. As these carps are economically very important research on cultivating these species of fish was initiated in India during early 1950’s to study and understand the biology of these economically important species, particularly, the major carps and to develop suitable technologies for various farming systems. These carps contribute approximately 75% to the Aquaculture production in India (FAO, 1997). the Catla (Catla catla Hamilton) the Rohu (Labeo rohita Hamilton), Mrigal (Cirrhinus mrigal Hamilton). The Aquaculture systems in India and its neighbour such as Bangladesh and Pakistan, mainly constitutes IMC’s viz. These intra-species GS values estimated for 2 stock were checked by one way ANOVA (SPSS version 16) and found to be significantly different at P Introduction The highest GS values, within the stock were obtained for Ganjam followed by Puri. The mean intra-species GS values were 0.7897± 0.663 for Puri stock and 0.836± 0.599 in case of Ganjam stock respectively. The result indicated that the two stocks of Catla fall under one phylogenetic cluster. In the present investigation, the genetic diversity of two stocks of Catla catla was studied through RAPD analysis and the phylogenetic cluster was done using UPGMA with NTSYS pc version 2.2 software. Therefore, this study was carried out to evaluate the genetic variation and phylogenetic relationship among the two different stocks of Catla catla in Orissa based on RAPD profiles. Little genetic information is available on Catla catla species in Puri and Ganjam Districts of Orissa state.

Inbreeding is a common scenario in all the hatcheries of Orissa with mass stocking of genetically inferior fry in hatcheries having the potential to cause feral gene introgression in to hatchery raised seeds. The natural breeding of Catla catla has become uncertain due to continuous degradation of habitat caused by environmental modification and manmade interventions, leading to decreased Catla populations in the state of Orissa. In India, Catla catla is found in almost all the major and minor rivers, lakes, beels and it is being cultured in all the states of India due to its high growth rate and high market price. The Catla carp (Catla catla Hamilton: 1822) is an Indian Major Carp and one of the major aquaculture species of India, Bangladesh, Myanmar (Burma) and Pakistan (Jhingran, 1986).

Ntsys Pc Version 2.2