Gynogenetic Nibea Induced By Oplegnathus Sperm And Preparation Of Pseudo-male Nibea

In this study, Nibea albiflora is the research object. It is mainly constituted by the content of two parts: Part one is the study named Nibea gynogenesis induced by Oplegnathus’ sperm; Part two is the preparation Gynogenetic Nibea of pseudo-male. The main results were shown as follows:(1)The fertilized eggs’ hatching rate decreased under 0~25s exposure time in the experiments which Oplegnathus’ sperm induced Nibea gynogenesis; within 25 ~ 45 s,fertilized eggs’ hatchability gradually increased; within 45 ~ 240 s, the hatchability gradually reduced,which has shown a significant “Hertwig” effect. Experimental results showed that the best Oplegnathus sperm inactivation time is at 45 s.(2)Cold shock experiments showed that: when the water temperature is at 2 ~ 3 ℃, 2min after fertilization, cold shock foe 8min, Gynogenetic hatchability is the highest which is at 21.23%. The offspring had been examined by flow cytometry, DNA content of Gynogenetic fry is quite equal with normal diploid, and twice as haploid.(3)Adding MT in the water will inhibit the growth of juvenile Nibea. By measuring the total length and the weight, Nibea showed no significant difference of full-length and weight at 30 days when treated with various concentrations; Nibea’s weight and total length of four experimental groups were lower than the control group at 70-100 days. In addition,in the three experimental groups(0.5μg/L, 1μg/L and 5μg/L), although the growth of which is lower than that of the blank group and the control group, among the three groups did not have significantly difference which suggesting that in a certain concentration range, with the increasing of MT concentration,the growth of Nibea will not be affected. The high concentration(10μg/L) treated groups has a minimum growth rate, especially at 70 days of age, the body weight growth is extremely slow.MT hormone concentrations within Nibea tolerance range, will not affect their survival rate. In each experimental group(0.5μg/L, 1μg/L, 5μg/L and 10μg/L), although the mortality rate is higher than 5%, but it did not show significant difference.MT hormones can induce Gynogenetic Nibea gonadal development into testis successfully. In 5μg/L treatment group, 45-day-old Gynogenetic Nibea gonadal began to turn into testis,which is 10 days earlier than normal.