摘要
在拟穴青蟹(Scylla paramamosain)育种实践中,建立了一种选择个体大小的策略,应用ISSR和RAPD标记技术并以拟穴青蟹雄性个体组建供试群体检验所建立的选择策略的有效性.ISSR与RAPD标记方法的分析数据都表明,大、中、小个体组的几个对应遗传参数值高低依次按中个体组、大个体组、小个体组排列.其基因多样性的Nei’s分析表明,ISSR分析所得到的总遗传多样性(Ht=0.322 3)、平均遗传多样性(Hs=0.270 1)、遗传分化系数(Gst=0.162 2),均高于RAPD分析得出的对应遗传参数值(Ht=0.274 6,Hs=0.233 6,Gst=0.149 3).基于ISSR数据的遗传分化系数表明大、中、小个体组组间遗传分化程度达到较高水平,而基于RAPD数据的遗传分化系数表明大、中、小个体组组间遗传分化程度达到中等水平.上述结果表明应用ISSR标记技术比应用RAPD标记技术能揭示出更加丰富的遗传变异信息.基于ISSR和RAPD分析数据的组间遗传分化系数表明,大个体组与小个体组间的遗传分化系数最高(Gst值分别为0.165 8、0.139 9),与中个体组间的次之(Gst值分别为0.156 6、0.127 2),中个体组与小个体组间的遗传分化系数最低(Gst值分别为0.050 5、0.082 4).基于Nei’s遗传距离的UPGMA聚类分析结果表明,ISSR和RAPD分析数据均支持大个体组优先分离.基于Dice’s系数的个体聚类分析结果也揭示了大个体组个体优先分离并呈现出单独聚类趋势.这表明ISSR与RAPD分析数据均支持了拟穴青蟹个体大小选择策略的有效性.此外,研究结果也表明:拟穴青蟹供试群体遗传多样性高低分布趋势与群体内的不同个体类型的数量分布趋势基本一致,呈正态分布趋势;大个体组的遗传多样性高于小个体组,或小个体组的遗传多样性高于大个体组并不影响大个体组作为育种材料的潜力.
A strategy for screening individual size of Mud crab (Scylla paramamosain) was established during a breeding activity. To corroborate the validity of this strategy, the ISSR and RAPD marker techniques were recommended to detect the genetic diversity of the tested populations consisting of male juvenile of Mud crab. The analyses based on ISSR and RAPD data show that several genetic parameters generated from mediumsize group are higher than those of bigsize group,then followed by those of smallsize group. Nei' s analysis of gene diversity shows that total genetic diversity( Ht = 0. 322 3 ), mean genetic diversity (Hs = 0. 270 1 ), and genetic differentiation coefficient( Gst -0. 162 2) from ISSR data are all higher than those corresponding genetic parameters from RAPD data (Ht = 0.274 6, Hs = 0. 233 6, Gst = 0. 149 3 ). The gene differentiation coefficient (Gst = 0. 162 2 ) from ISSR data shows that the genetic differentiation between groups have achieved high level. The gene differentiation coefficient (Gst = 0. 149 3) generated from RAPD data suggests mediumlevel genetic differentiation between groups. Therefore,compared to the application of RAPD marker in the same populations, using ISSR marker can disclose much plentiful genetic variations. The genetic differentiation coefficients between groups point out the highest between the big size group and the small size group( Gst =0. 165 8,0. 139 9) ,followed by the value between the big size group and the medium size group( Gst =0. 156 6,0. 127 2) ,and the lowest between the medium size group and the small size group( Gst =0. 050 5,0. 082 4). The UPGMA clustering based on Nei' s genetic distance shows that the big size group preferentially separate from the tested population. The individual clustering on Dice' s coefficient also shows a same result, especially in ISSR data analysis. Hence, both ISSR and RAPD data analyses support the validity of this screening strategy. Furthermore, the genetic diversity of the tested population shows a tendency of normal distribution, so does the number of different individual size types. In fact, compared to those of the small size group, higher or lower genetic diversity of the big size group has no effect in the future breeding.
出处
《台湾海峡》
CAS
CSCD
2012年第1期58-64,共7页
Journal of Oceanography In Taiwan Strait
基金
广西教育厅科研资助项目(200809MS095)
广西自然科学基金资助项目(桂科自0991189)
广西海洋生物技术重点实验室开放基金资助项目(GKLMBT-0801)