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柞蚕品种资源数量性状的遗传多样性分析,有利于柞蚕新品种选育过程的优良亲本选配及性状改良.在对辽宁蚕区保存的39份二化性柞蚕品种资源的7项数量性状连续5年进行统一调查的基础上,通过变异系数、多样性指数和聚类分析明确其遗传多样性.除实用孵化率和克卵粒数2项性状的变异系数较低外,产卵数量、产卵量、全茧量、茧层量和茧层率5项性状均有较高的变异系数,其中产卵数量、产卵量和茧层量的变异系数分别达到了11.29％、13.87％和11.86％,并且各项性状的分布频率表现出一定的集中性.除实用孵化率的Shannon-Weaver多样性指数较低外,产卵数量、产卵量、克卵粒数、全茧量、茧层量和茧层率的遗传多样性指数均较高,表明这些性状蕴含丰富的遗传变异.利用DPS数据处理系统,以最短距离法对距阵结果进行聚类分析,将39份柞蚕品种资源分成6个类群,其中4个从国外引进的改良品种聚为一大类群,印证了柞蚕品种资源的亲缘关系与地理来源有关.上述结果显示供试39份二化性柞蚕品种资源7项主要数量性状的遗传多样性丰富,尤其是产卵数量、产卵量和茧层量等性状有较大的遗传潜力,可应用于品种改良;而实用孵化率的遗传潜力小,育种过程不易进行性状改良.“,”Analysis on genetic diversity of quantitative traits helps parental selection and trait innovation in the course of tussah silkworm breeding.Based on 5-year continuous investigation on 7 quantitative traits of 39 bivoltine tussah germplasm resources preserved in Liaoning tussah regions,the genetic diversity was analyzed by means of variation coefficient,diversity index and clustering analysis.Except for practical hatchability and number of eggs per gram,all the other 5 traits,namely number of laid eggs,weight of laid eggs,single cocoon weight,cocoon shell weight and cocoon shell rate,showed high variation coefficient.The variation coefficient of number of laid eggs,weight of laid eggs and cocoon shell weight reached 11.29％,13.87％ and 11.86％,respectively,and the distribution frequency of each trait showed certain centrality.Except for practical hatching rate,all the other traits including number of laid eggs,weight of laid eggs,number of eggs per gram,single cocoon weight,cocoon shell weight and cocoon shell rate showed higher Shannon-Weaver diversity index,which revealed abundant genetic variation in these traits.Cluster analysis on the data matrix had been conducted by DPS data processing system with the method of shortest distance clustering.The result showed that the 39 tussah silkworm germplasm resources were classified into 6 groups.The 4 imported and innovated varieties were classified into one large group,verifying the genetic relationship of tussah silkworm germplasm resources was related to their geographic origins.The above result indicates abundance of genetic diversity in 7 primary quantitative traits among 39 bivoltine tussah silkworm germplasm resources.Especially,the number of laid eggs,weight of laid eggs and cocoon shell weight have high genetic potential,which can be applied for variety improvement.On the other hand,practical hatchability has low genetic potential,which makes it difficult to be improved during breeding course.