三倍体白鲫的生物学特性

由人工诱导的异源四倍体白鲫雄鱼与正常的二倍体白鲫雌鱼交配获得的异源三倍体白鲫，其主要生物学特性同二倍体白鲫进行比较研究表明，三倍体白鲫具有体形较大、相对体高和相对尾柄高较高、侧线上下鳞数目较多的形态特征，仍保留着二倍体白鲫以浮游植物为主的植食性营养方式，雌雄均不育，比二倍体生长快，网箱养殖１１２天后，体重比二倍体平均增加３２．３８％。试验证实三倍体白鲫是一个具有养殖生产前景的新对象。

BIOLOGICAL CHARACTERS OF TRIPLOID JAPANESE PHYTOPHAGOUS CRUCIAN CARP

Heterologous triploid (3n)Japanese phytophagous crucian carp(Carassius auratuscuvieri T. et S.)were produced by mating heterologous tetraploid (4n) male with diploid (2n)female(Carassius auralus cuvieri).Its main biological characteristics were compared withthat of diploid maternal fish(2n).The triploid has the characteristics of relatively largerbody size, higher body height and caudal peduncle height,more scales above lateral line andbelow lateral line than that of diploid. However,it mantains the herbivorous feeding habit ofdiploid that mainly live on phytoplankton. Male and female were all sterile and have highergrowth rate than that ofdiploid.After cuItured in net cage for 112 days, the body weight oftriploid increased 32.38% than that of diploid. The above results indicate that triploidcrucian carp is a new cuIture object that possesses good prospects.