Qin Yanping, Noor Zohaib, Li Xingyou, Ma Haitao, Li Jun, Zhou Yinyin, Mo Riguan, Zhang Yuehuan, Yu Ziniu
CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301 China.
Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 510301 China.
Mar Life Sci Technol. 2021 Jul 28;3(4):463-473. doi: 10.1007/s42995-021-00107-w. eCollection 2021 Nov.
The production of an all-triploid population by mating tetraploid males with diploid females is the best and most fundamental method for the large-scale production of triploid oysters. Obtaining a stable tetraploid population is essential for guaranteed production in industrialized triploid cultivation. and are important oyster breeding species in southern China, and have great economic value. However, there are not any published data on inducing tetraploid or . Therefore, we investigated tetraploid induction in these two oyster species by inhibiting the PB1 release in diploid fertilized eggs using Cytochalasin B (CB) under 31 °C, 15 ‰ salinity. The results confirmed that the optimal tetraploid induction conditions for were a CB concentration of 0.50 mg/L with induction starting at 9.0 min after fertilization, and stopping at 21.0 min after fertilization; the induction efficiency index reached 0.123 under these conditions. The optimal tetraploid induction conditions for were a CB concentration of 0.50 mg/L, with induction starting at 7.5 min after fertilization and stopping at 18 min after fertilization; the induction efficiency index could be as high as 0.281 under these conditions. However, we confirmed that the tetraploid rate decreased with larval growth, and no tetraploids were detected in the juvenile period of either or . This may be attributed to the very low survival of the tetraploid larvae induced by this method, especially as most tetraploid larvae died during the first three days. In summary, it is simple to directly induce tetraploid and larvae by inhibiting the PB1 release of diploid zygotes, but the low survival rate makes it challenging to obtain viable juvenile tetraploids.
通过四倍体雄性与二倍体雌性交配产生全三倍体群体是大规模生产三倍体牡蛎的最佳且最基本的方法。获得稳定的四倍体群体对于工业化三倍体养殖的产量保障至关重要。 和 是中国南方重要的牡蛎养殖品种，具有很高的经济价值。然而，目前尚无关于诱导四倍体 或 的公开数据。因此，我们在31℃、盐度15‰的条件下，使用细胞松弛素B（CB）抑制二倍体受精卵中PB1的释放，研究了这两种牡蛎的四倍体诱导情况。结果表明， 的最佳四倍体诱导条件为CB浓度0.50mg/L，受精后9.0min开始诱导，21.0min停止诱导；在此条件下诱导效率指数达到0.123。 的最佳四倍体诱导条件为CB浓度0.50mg/L，受精后7.5min开始诱导，18min停止诱导；在此条件下诱导效率指数高达0.281。然而，我们证实四倍体率随幼虫生长而降低，在 或 的幼体期均未检测到四倍体。这可能归因于用该方法诱导的四倍体幼虫存活率极低，尤其是大多数四倍体幼虫在头三天内死亡。综上所述，通过抑制二倍体合子的PB1释放直接诱导 及 幼虫成为四倍体操作简便，但低存活率使得获得存活的四倍体幼体具有挑战性。
