荧光茧色性连锁家蚕品种雌雄个体中肠的色素透过性及荧光茧色的遗传分析

Pigment Permeability Through Midgut of Male and Female Individuals and Genetic Analysis on Fluorescence Cocoon Color in Sexlinked Bombyx mori Varieties

用荧光主色素跟踪法和性染色体标记法,对家蚕荧光茧色性连锁遗传类型进行研究。对依据家蚕荧光茧色判别性别起决定作用的荧光黄色素合成由多对基因控制,蚕茧的荧光黄色为数量性状遗传,且控制该性状的基因主要位于常染色体上。在雌蚕茧为荧光紫色、雄蚕茧为荧光黄色的家蚕品种春玉和雌、雄蚕茧均为荧光紫色的家蚕品种皓月B的杂交后代群体中,蚕茧的荧光黄色与荧光紫色均能正常表现,控制2种荧光色素合成的基因不互为等位基因,不存在显隐性关系。造成荧光茧色性连锁家蚕品种雌雄茧荧光色不同的原因,是雄蚕茧中的荧光黄色素含量显著高于雌蚕茧,出现这种差异是由于与雄性幼虫相比,雌性幼虫的中肠不能有效地透过荧光黄色素,而是富集于中肠中。

Fluorescent main pigment tracing and sex chromosome labeling were employed to characterize the sex-linked inheritance patterns of fluorescence cocoon color in the silkworm,Bombyx mori. The results indicate that the synthesis of yellow fluorescent pigment,which plays a decisive role in distinguishing the sex of fluorescence cocoon color in silkworm,is controlled by multiple genes and is a quantitative genetic trait. Besides,the genes which control this trait are mainly located on euchromosomes. Yellow and purple fluorescent pigments were both observed inhybrid progeny of Chunyu,a silkworm variety of which female cocoons show purple fluorescence and male cocoons show yellow fluorescence,and Haoyue B,a silkworm variety of which both female and male cocoons show purple fluorescence. The genes controlling formation of purple and yellow fluorescent pigments are not allele of each other and thus have no dominancerecessiveness relationship. The reason that causes different fluorescence color between male and female cocoons of fluorescence sex-linked silkworm varieties is that the cocoons of male individuals have significantly higher content of yellow fluorescent pigment than those of female individuals. This difference is due to ineffective permeability of the yellow pigments through midgut of female larvae compared to male larvae,which leads to enrichment of yellow fluorescent pigments in the midgut of female larvae.