强健性家蚕品种夏芳×秋白的斑纹限性化改育

Improvement on Sex-limited Marking of Silkworm Variety Xiafang×Qiubai with High Vitality

以保存的斑纹限性家蚕品种资源材料K304、川30为母本,以西南蚕区推广应用的强健性无斑纹(姬蚕)家蚕品种夏芳、秋白为父本进行杂交,赋予现行家蚕优良品种便于雌雄鉴别的性能。经过连续3代回交和多代系统选择,初步选育出主要经济性状接近或超过其雄性亲本的斑纹限性家蚕品种蜀63、限16,并根据其雄性亲本的杂交组合形式组配新的杂交组合蜀63×限16。室内饲养鉴定表明,蜀63×限16的健康性和茧丝质成绩均达到或超过雄性亲本杂交组合夏芳×秋白的水平,解舒丝长、解舒率、洁净、万蚕产丝量分别提高3.96%、2.73个百分点、1.05分、2.77%,改育前后的杂交组合主要性状的杂种优势率也表现一致。改育品种的杂交组合蜀63×限16达到了既可通过斑纹限性实现雌雄鉴别,并且主要经济性状又优于原雄性亲本杂交组合夏芳×秋白的预期目标。

In order to confer sex-limited marking trait on current excellent silkworm variety for female and male discrimination,the preserved silkworm variety materials K304 and Chuan 30 with sex-limited marking were used as female parents and the silkworm varieties Xiafang and Qiubai with plain marking and high vitality were used as male parents for improvement on sex-limited marking of commercial silkworm variety popularized in southwest sericultural area of China.After three generations of consecutive backcrossing and many generations of systematical selection,two sex-limited marking silkworm varieties Shu 63 and Xian 16,whose main economical characters were similar to or better than those of their male parents,were obtained.Consequently,a new hybrid combination Shu 63×Xian 16 was prepared based on cross-combination form of its male parents.The results of laboratory rearing showed that the healthiness and cocoon filament quality of Shu 63×Xian 16 were similar to or better than those of its male parent hybrid combination Xiafang×Qiubai.The length of non-broken cocoon filament,reelability,neatness and cocoon weight per 10,000 larvae was increased by 3.96%,2.73 percentage points,1.05 points and 2.77% respectively.Meanwhile,the hybrid vigor rate of major economical character was similar before and after the improvement.The improved hybrid combination Shu 63×Xian 16 had reached the expected objectives： to discriminate the female and male through sex-limited marking and to possess main economical characters better than those of its male parent hybrid combination Xiafang×Qiubai.