6-DMAP和低渗诱导长牡蛎“海大2号”三倍体的研究

A Study on the Effects of 6-DMAP and Hypotonic Treatment in Inducing Triploid Crassostrea gigas“Haida No.2”

为探索低渗和6-二甲基氨基嘌呤(6-DMAP)诱导长牡蛎(Crassostrea gigas)三倍体最佳条件以及6-DMAP和低渗配合使用诱导三倍体的可行性,本研究通过低渗、6-DMAP以及6-DMAP与低渗配合三种方法诱导长牡蛎“海大2号”三倍体。研究显示,低渗处理组中,当第一极体(PB1)出现40%时,在盐度为8的低渗海水中持续处理15 min,综合评价指数最高,为34.33%,此时2日龄长牡蛎的三倍体率和存活率分别为73.77%±1.89%和45.78%±6.23%,8日龄长牡蛎的三倍体率和存活率分别为50.65%±4.89%和21.17%±5.54%。6-DMAP处理组中,当PB1出现40%时,75 mg/L的6-DMAP持续处理15 min,综合评价指数最高(36.52%),此时2日龄长牡蛎的三倍体率和存活率分别为74.81%±0.68%和46.30%±1.54%,8日龄长牡蛎的三倍体率和存活率分别为60.37%±0.61%和30.25%±2.85%。6-DMAP和低渗配合组中,当PB1出现40%时,在盐度为8的低渗海水中,以50 mg/L的6-DMAP持续处理15 min,综合评价指数最高(36.18%),此时2日龄长牡蛎的三倍体率和存活率分别为74.34%±3.49%和45.07%±4.41%,8日龄长牡蛎的三倍体率和存活率分别为68.23%±2.52%和40.42%±4.30%。综合比较以上三种方法,通过6-DMAP和低渗配合诱导获得三倍体的倍率更稳定,幼虫存活率更高。研究结果可为长牡蛎“海大2号”三倍体培育提供参考资料。

In order to explore the optimal method of inducing triploid Crassostrea gigas“Haida No.2”,three methods including 6-dimethylaminopurine(6-DMAP),hypotonic treatment and the combination of 6-DMAP and hypotonicity treatment were optimized.The results showed that in the hypotonic treatment group,when 40%of the first polar body(PB1)appeared and the fertilized eggs were treated for 15 min in hypotonic seawater with a salinity of 8,the highest evaluation index was 34.33%.In this case,the triploid rate and survival rate on day 2,triploid rate and survival rate on day 8 were 73.77%±1.89%,45.78%±6.23%,50.65%±4.89%and 21.17%±5.54%,respectively.In the 6-DMAP treatment group,when the fertilized eggs appeared 40%PB1 and treated with 75 mg/L 6-DMAP for 15 min,the highest evaluation index of 36.52%was observed.In this case,the triploid rate and survival rate on day 2,triploid rate and survival rate on day 8 were 74.81%±0.68%,46.30%±1.54%,60.37%±0.61%and 30.25%±2.85%,respectively.In the combination groups of 6-DMAP and hypotonic treatment,when 40%of eggs appeared PB1 and treated with 50 mg/L 6-DMAP in hypotonic seawater with a salinity of 8 for 15 min,the highest evaluation index of 36.18%was obtained.In this case,the evaluation index,the triploid rate and survival rate on day 2,triploid rate and survival rate on day 8 were 74.34%±3.49%,45.07%±4.41%,68.23%±2.52%and 40.42%±4.30%,respectively.A comprehensive comparison of the above three methods showed that the combination of 6-DMAP and hypotonic treatment induced higher stable triploid rate with higher larval survival rate.The results of this study provided useful information for inducing triploid C.gigas“Haida No.2”.