【摘要】 用细胞松弛素B(C.B)(浓度1.2—1.5mg/L)和低温(12.0℃)处理诱导合浦珠母贝Pinctada martensii(D.)产生多倍体。抑制第一极体的三倍体诱导率达到40％左右;而抑制第二极体的三倍体诱导率分别为77％和52％。随着C.B处理时间的延长,则出现一定数量的五倍体。亚致死温度是低温诱导多倍体的合适温度。随着处理温度的降低和时间的延长,孵化率急剧下降,且非整倍体数量增加。结果提示,C.B处理和低温处理诱导多倍体的机制有所不同;后者不仅抑制极体排放和细胞分裂,而且影响染色体复制和分离。 抑制第一极体的C.B处理组的幼虫日增长率和幼贝大小均显著超过对照组。更多还原

【Abstract】 Polyploid induction by application of cytechalasin B(C.B)and cold shocks during early development soon alter fertilization was attempted in Pinctada martensii(D. ),and have resulted into the pilot culture of juveniles. When the experimental group was treated with 1.2- 1.5mg/l C.B for 15 minutes, or cold shocks for 80-90 minutes at 12℃, the incidence of triploids was about 40% for the retention of the first polar body with either treatment, and over 76% and 52% for the retention of the second polar body respectively. This indicated that the retention of the second polar body is much easier that of the first one. A quantity of pentaploids occurred as treatment with C.B was prolonged, smce C.B inhibited the first and the second polar body both at the same time. Sublethal temperature might be suitable for polyploid inducement of cold shocks. Hatching rate decreased obviously and the number of aneuploids increased rapidly when treating temperature was decreased and duration prolonged. The results suggest that mechanisms of polyploid inducement with C.B treatment and cold shocks are not the same. The former inhibits polar body extrusion and cell division, the latter not only inhibits polar body extrusion and cell division, but also interfered with replication and segregation of chromosomes.Daily growth of larvae produced by inhibiting the first polar body with C. B was higher and their size larger, but daily growth of those produced by inhibiting the second polar body with C.B was significantly lower.更多还原