鲤和草鱼杂交四倍体及其回交三倍体草鱼杂种的研究

进行了兴国红鲤♀×草鱼♂的杂交,杂种一代染色体数为142—156,众数值为146—152,系染色体自动加倍的异源四倍体。其外形和习性接近母本,两性均能成熟,雌、雄鱼分别与草鱼进行了回交。以草鱼为母本,杂种一代为父本的回交子代全部为草鱼形,草食性。以杂种一代为母本,草鱼为父本的回交子代一部分象草鱼,一部分象鲤,但草鱼形子代成活率较低,两个回交组合的子代均为三倍体,染色体数98—100,众数值98。1983年获得的杂种一代♀×草鱼♂的鲤鱼形回交杂种,已于1986年性成熟,雌、雄鱼分别与草鱼再次回交,获得了二次回交杂种。测定了红鲤、草鱼、杂种一代及其与草鱼回交子代的乳酸脱氢酶和过氧化物酶的同工酶,它们各有不同的电泳图谱。

STUDIES ON TETRAPLOID HYBRID BETWEEN RED COMMON CARP (CYPRINUS CARPIO) AND GRASS CARP (CTENOPHARYNGODON IDELLUS) AND ITS BACKCROSS TRIPLOID

Hybridization between red common carp and grass carp was conducted. The hybrid, a tetraploid through automultiplication of chromosomes, posses feature and habit like maternal parent and can develop into both sexes. The female and male hybrids F_1 when backcrossed with both sexes of grass carp, produce triploid offsprings containing 98 chromosomes, but their feature and habit are different. The backcrossing offsprings from female grass carp and male hybrid F_1 are herbivorous like grass carp. However, backcrossing offsprings from female hybrid F_1 and male grass carp separate into two types: common carp-like or grass carp-like. Common carp-Like of backcrossing hybrids are able to mature and reproduce offspring.LDH and Peroxidase isozymes of all concerned fish were determined with blood serums. The zymogram patterns of them are different.