日本沼虾野生群体与养殖群体杂交、回交后代的形态特征和生产性能

The Morphological Characters and Growth Performance of Hybrid and Backcross Progenies from Crosses between Wild and Cultured Prawn Macrobrachium nipponensis

以日本沼虾野生群体与多年自繁的养殖群体为亲本进行正反交,再以杂交虾F1与野生虾进行回交,对养殖虾的种质进行改良。结果显示,正反交及其回交的虾苗产量高于双亲自繁的虾苗产量,分别比野生虾和自繁虾的苗产量高20.17%和25.61%,差异显著。获得的杂交虾F1及回交后代的主要经济形态特征及生产性能高于双亲,其中肥满度、头胸甲长、宽、腹部长等性状与养殖虾的差异达到显著水平(P<0.05)。杂交虾F1和回交虾的单位面积净利润分别为多年养殖的自繁虾的3倍和2倍。经过杂交与回交,初步获得了形态特征和生产性能均优良的日本沼虾养殖群体。

The reciprocal crosses between cultured and wild prawn（Macrobrachium nipponensis）,and a back-cross of hybrid F1 with the wild population from Lake Taihu were performed to improve existing germplasm of the prawn for aquaculture.The results showed that the reciprocal crosses and backcross provided more juvenile prawn than that from self-fertilization of cultured or wild populations,and increased statistically significantly in production by more than 20.17% and 25.61%,respectively,compared with those from self-fertilization in Taihu wild population.The hybrid F1 and backcross progenies were showed higher performance in key economic morphological characters and production performance than both maternal and paternal broods,and significant differences（P0.05）in condition factors,carapace length,width,abdomen length and other characters occurred between cultured population and progenies of reciprocal crosses and backcross.The net profits per unit area in prawn production with hybrid F1 and backcross progenies were three or two times higher than that in cultured population,respectively.Therefore,new prawn germplasms with modified morphological characters and improved growth performance could be achieved via reciprocal crosses and backcross.