【摘要】 利用化学诱变剂5-溴尿嘧啶(5-Bromouracil,5-BrUra)处理不同发育时期中国明对虾(Fenneropenaeus chinensis)胚胎,统计孵化率,根据统计学分析结果获得最佳处理条件,并探讨温度、盐度和pH对5-溴尿嘧啶处理效果的影响以及5-溴尿嘧啶对中国明对虾幼体发育的影响。结果表明:(1)5-溴尿嘧啶诱变中国明对虾的最佳起始处理阶段为原肠期,达到接近半致死效果的浓度和处理时间组合分别为0.5mg/mL6h、0.3mg/mL15h和0.1mg/mL24h;(2)温度和盐度对5-溴尿嘧啶诱变中国明对虾胚胎的效果可产生显著影响,而pH影响不显著;(3)5-溴尿嘧啶能影响中国明对虾幼体前期(无节幼体N→溞状Ⅲ)发育,而对溞状Ⅲ至仔虾期间的幼体发育没有显著影响诖私锥危?5-溴尿嘧啶处理后孵化出的幼体能够正常变态。更多还原

【Abstract】 Artifi cially induced mutation by chemical mutagens plays an important role in new variety breeding of crops and micro-organisms. And a lot of new strains with new commercial traits have been produced. However, few studies are reported on mutagen’s application in aquatic organism breeding,especially in marine shrimps. In the present study,embryos of marine shrimp Fenneropenaeus chinensis at different developmental stages were treated by 5-bromouracil (5-BrUra) at different concentration and duration time. To investigate the influence of environmental factors on the effects of 5-BrUra,three temperature (17,20 and 23 ℃ ),three salinity (24,30 and 36) and three pH value(7.6,8.1 and 8.6)were set and orthogonal test was adopted in this test. Metamorphic rates and survival rates were obtained under different treatment conditions. Results are as follows:1)The optimum initial embryonic stage for mutagen treatment was gastrula stage,and three combinations of treating concentration and duration which could induce 50% lethal death were screened as 0.5 mg/mL and 6 hours duration,0.3 mg/mL and 15 hours duration,and 0.1 mg/mL and 24 h duration,respectively. 2)Temperature and salinity signifi cantly affected the effects of 5-BrUra on hatching rate(P < 0.05) while no signifi cant effects of pH was observed within the experimental pH ranges(P > 0.05). 3)From the stage of zoea Ⅲ,no meaningful differences were observed on the metamorphosis rates between 5-BrUra treatment and control groups,and 5-BrUra treated larva could normally metamorphosize,suggesting that 5-BrUra mainly affect larva on the early developmental stages from nauplius to zoea Ⅲ .更多还原