6-DMAP诱导太平洋牡蛎三倍体——4.四倍体现象的研究

Triploid Pacific Oyster (Crassostrea Gigas) Induced with 6-DMAP 4. Studies on the Tetraploid

１９９６～１９９７年，在进行６－二甲基氨基嘌呤（６－ＤＭＡＰ）诱导太平洋牡蛎产生三倍体的实验过程中，发现一定数量的四倍体。解剖法获取精卵，人工授精。染色体倍性鉴别采用染色体计数法。（１）三因素四水平Ｌ１６（４５）正交设计。试验平行重复２次。最高四倍体诱导率为４０．０±０．０％。太平洋牡蛎四倍体各诱导因素的最优水平组合：当精卵混合２０ｍｉｎ时，将受精卵浸泡在含６－ＤＭＡＰ４５０μｍｏｌＬ－１的海水中１０ｍｉｎ；决定四倍体产生的三因素的主次顺序：６－ＤＭＡＰ浓度→诱导时机→诱导持续时间。（２）三因素三水平Ｌ９（３４）正交设计。试验平行重复３次。最高四倍体诱导率为９．６±４．９％。诱导太平洋牡蛎四倍体各因素的最优水平组合：当５０％受精卵出现第一极体时，将受精卵浸泡在含６－ＤＭＡＰ４５０μｍｏｌＬ－１的海水中１５ｍｉｎ；决定四倍体产生的三因素的主次顺序：诱导时机→６－ＤＭＡＰ浓度→诱导持续时间。

In 1996￣1997, while a number of experiments were undertaken to induce triploids of Pacific oysters, Crassostrea giass by inhabiting the polar bodies of the zygotes with 6-Dimethylaminopurine (6-DMAP), some tetraploid embryos were found at the same time. The sperms and ova were obtained with anatomy method. The ova were inseminated artificially. Ploidy was identified by chromosome counts. (1) L 16 (4 5) design was selected to engage in orthogonal experiment of three factors at four levels. The experiments were repeated two times. The highest tetraploidy was 40.0±0.0%. The best level combination of induced tetraploid in Pacific oyster was: at 20 min after the sperms and eggs were confused, rinsed the zygotes in sea water with 450 μmolL -1 6-DMAP for 10 min. The sequence of the three factors in the genesis of tetraploid is: 6-DMAP concentration→induction occasion→induction duration. (2.)L 9(3 4) design was selected to engage in orthogonal experiment of three factors at three levels. The experiments were repeated three times. The highest tetraploidy was 9.6±4.9%, the embryo hatch rate of this experimental group was 30.8±5.3%, the D-shaped larvae abnormality rate was 36.9±3.1%, and the triploidy was 58.9±6.7%. The best level combination of induced tetraploid in Pacific oyster was: when the first polar bodies were found in 50% zygotes, rinsed the zygotes continuously in sea water with 450μmolL -1 6-DMAP for 15 min. The sequence of the three factors in the genesis of tetraploidy was induction occasion→6-DMAP concentration→induction duration.