合浦珠母贝人工诱导四倍体的研究

A STUDY ON INDUCTION OF TETRAPLOID IN PEARL OYSTER,PINCTADA MARTENSII(D.)

用细胞松驰素B（CB）、聚乙二醇（PEG）和静水压抑合浦珠母贝Pinctadamarlensii（D．）制第1次卵裂以及CB抑制极体形成诱导四倍体。CB抑制第1次卵裂在早期胚胎2-4细胞阶段发现四倍体，但8细胞阶段以后四倍体胚胎消失。PEG和PEG＋CB能诱导细胞融合产生四倍体，但处理组幼虫在担轮期死亡。CB抑制极体形成能诱导出较高比例的四倍体，在胚胎初期和担轮幼虫期分别占40％和30％以上。处理组幼虫进行培育，附苗后当贝苗长成4-5cm大小时通过鳃细胞染色体倍性检查，却没有发现四倍体。文中对四倍体是否能成活进行了讨论。

Tetraploid induction is attempted in Pearl oyster,Pinctada martensii(D.)by inhibiting mitosis I with cytochalasin B(CB),polyethylene glycol(PEG) orhydrostatic pressure treatments,and by blocking the release of polar body I with CBtreatment. Inhibition of mitosis I with CB produced tetraploids, which are found at thestages of 2-4 cells but not 8 cells. PEG or PEG+CB treadments can lead cellfusion to produce tetraploids, but the larvae of the treated groups do not survive thetrochophore stage. Polar body being blocked with CB can produce higher levels oftetraploids, up to 40% and 30% respectively at the early embryo stage and thetrochophore stage. No tetraploids are found in the cultUred 4-5cm juveniles of thetreated group when ploidy determination is conducted by counting chromosomes fromgill tissue. The viability of tetrapliod is discussed in mis study.