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The present study was conducted to measured heavy metals in cyprinid fishes in rivers of District Khuzdar Balochistan, Pakistan. In the present study, 25 fish samples were collected that belonged to 8 order of 13 families, The Cyprinidae family had the largest number of eight fish species. Present study is focused on Heavy metals in cyprinid fishes. Heavy metals accumulation like Zinc, Manganese, Copper, and Nickel was evaluated in water and various organs of fishes. Atomic Absorption Spectroscopy was used for the identification of these heavy metals in fish species and water bodies. The average concentration (mg/L) of Zn 0.26-0.41, Mn 0.030- 0.073, Cu 0.017-0.080 and NI 0.14-0.79 were observed in water. The Concentration (mg/L), of Zn Conc 0.383-.028 Mn Conc .073- .030 Cu Conc 080-.017 NI Conc .79-.14. The concentration of heavy metals was found both similar and varied simultaneously across the whole research area. Zinc concentration was reported highest, whereas Copper was at the lowest concentration in all fish species .The concentration of heavy metals, in all the fish species under this study, was above the threshold of WHO limits.

The popularity of genetically modified insect resistant (Bt) cotton has promoted large scale monocultures, which is thought to worsen the problem of crop genetic homogeneity. Information on genetic diversity among Bt cotton varieties is lacking. We evaluated genetic divergence among 19 Bt cotton genotypes using simple sequence repeat (SSR) markers. Thirty-seven of 104 surveyed primers were found informative. Fifty-two primers selected on the basis of reported intra-hirsutum polymorphism in a cotton marker database showed a high degree of polymorphism, 56% compared to 13% for randomly selected primers. A total of 177 loci were amplified, with an average of 1.57 loci per primer, generating 38 markers. The amplicons ranged in size from 98 to 256 bp. The genetic similarities among the 19 genotypes ranged from 0.902 to 0.982, with an average of 0.947, revealing a lack of diversity. Similarities among genotypes from public sector organizations were higher than genotypes developed by private companies. Hybrids were found to be more distant compared to commercial cultivars and advanced breeding lines. Cluster analysis grouped the 19 Bt cotton genotypes into three major clusters and two independent entries. Cultivars IR-3701, Ali Akbar-802 and advanced breeding line VH-259 grouped in subcluster B2, with very narrow genetic distances despite dissimilar parentage. We found a very high level of similarity among Pakistani-bred Bt cotton varieties, which means that genetically diverse recurrent parents should be included to enhance genetic diversity. The intra-hirsutum polymorphic SSRs were found to be highly informative for molecular genetic diversity studies in these cotton varieties.