中文摘要：

通过对家蚕基因资源库保存品系的性状调查,发现一种幼虫眼状纹变异——心形眼纹（cordiform eye-spot,ces）,其特征是：幼虫眼纹呈倒心型,相当于正常型眼纹的中间部分,色浅。与正常型进行杂交试验,表明该突变为隐性遗传,外显率稍低;与各染色体标记基因进行连锁分析,确认突变基因ces属于第14染色体;育成青熟油蚕（oa）与ces的双隐性系统后,通过ces与oa和Nd-s（丝胶茧）的三点测验,初步将ces基因定位于家蚕连锁图谱第14连锁群的50.7 cM位点,表示为ces（14-50.7）。

英文摘要：

A novel mutant in eye spot of larva,named cordiform eye-spot（ces）,was discovered during a survey to characteristics of the preserved silkworm genetic resources.It is characterized with a light color and obcordate eye spot,which is equivalent to the central part of a normal eye spot.Hybridization of the mutant with the normal one indicated that this mutation is controlled by a recessive gene which has a relatively low penetrance.Linkage analyses with marker genes of each chromosome indicated that the mutant gene ces belongs to the 14th linkage group.After having successfully bred the double recessive line with genes oa（aojuku translucent） and ces,a three-point test among ces,oa and Nd-s（sericin cocoon） showed that the gene locus of ces is at 50.7 cM on the 14th silkworm linkage group and is thus designated as ces（14-50.7）.