柞蚕杂种优势的研究与利用

Study and Utilization on Heterosis of Tussah Silkworm

我国自20世纪70年代开始系统开展柞蚕杂种优势的研究,从柞蚕不同经济性状的杂种优势分析,到通过重要生化酶指标预测主要经济性状的杂种优势表现,为柞蚕优良新品种选育奠定了理论基础。依据对交亲本的亲缘关系、遗传特性、主要性状表现,采用二元、三元或多元杂交形式组配的柞蚕优良杂交组合,使生产上推广的柞蚕新品种较大程度地发挥了增产增收作用,生产上柞蚕杂交种的普及率已达到90%以上。今后应充分利用现代分子生物学技术手段,加强柞蚕重要经济性状的遗传规律研究及育种材料的创新,提高杂种优势的利用率;针对柞蚕杂交组合的特殊性,在生产上采用合理的放养利用模式,并严格按杂交形式繁育优势杂交组合的对交品种,保证生产用杂交种的品质。

The study and utilization of heterosis in tussah silkworm has been conducted as early as 1970s in China.Covering analysis on heterosis between different economic traits and predicting heterosis performance of each economic trait by means of various enzymes,the studies have provided a solid theoretical basis for tussah silkworm cross breeding.According to the genetic relationship and characteristic,and the phenotypes of major traits of each parental variety,different forms of crossing,e.g.2-way-crossing,3-way-crossing and poly-crossing,were adopted to prepare excellent tussah silkworm combinations so as to increase productivity of the new breeds.The popularity rate of tussah silkworm hybrids in mass production has been raised up to more than 90%.Hereafter,future genetic studies on important economic traits and innovations of breeding materials of tussah silkworm should take full advantage of modern molecular biological technology so as to promote the utilization of tussah heterosis.Nevertheless,as for mass production,suitable rearing methods should be adopted in accordance with the characteristics of each tussah silkworm combination,and the cross parents of hybrid combinations with heterotic vigor must be reproduced in strict hybrid pattern to ensure the seed quality of hybrids.