摘要 : Field trials were conducted to assess the growth performance of two stocks (new breed, Amur and existing stock) of common carp, Cyprinus carpio under polyculture at nine different locations of Karnataka. Amur, a Hungarian stock of... 展开 Field trials were conducted to assess the growth performance of two stocks (new breed, Amur and existing stock) of common carp, Cyprinus carpio under polyculture at nine different locations of Karnataka. Amur, a Hungarian stock of common carp introduced to Karnataka under DFID carp genetics project during 2000. This stock was identified as best breed after its evaluation with other five stocks and was released for commercial production in 2006. As a part of evaluation, the growth performance of amur was assessed compared to existing stock under polyculture over a period of 28 weeks. Polyculture comprised common carp (Amur and existing stock), catla, grass carp and silver carp in the ratio of 4:4:1:1 at a stocking density of 5,000 fingerlings/ha. Results indicate that amur and existing stock of common carp attained a mean body weight of 583.03+or-18.36 g and 484.60 g+or-19.69 g respectively. The mean body weight of Amur stock was significantly higher than that of existing stock. Amur stock registered 20.31% faster growth over the existing stock. Survival rates of Amur and existing stocks were 76.63+or-1.23 and 77.38+or-1.35, respectively and were insignificant. Amur stock showed consistently better growth over existing stock in all the locations. Thus, the Amur stock has greater practical significance in low-input aquaculture systems due to its better growth than the existing stock. 收起