硒对家蚕生长发育的调控及其在体内富集的机理

硒的生物学效应在植物、哺乳动物和医学中得到了深入的研究，家蚕是一种典型的经济模式昆虫，家蚕的硒生物学效益至今还没有报道。前期我们以P50蚕品种作为研究对象，明确了25 μM的硒添食后，家蚕的体重显著增加、幼虫期均有明显延长、蛹期无显著差异、全茧量和蛹重显著升高；家蚕幼虫具有富集硒的特征，富集能力为精巢（卵巢）>头>后肠≈丝腺>表皮>脂肪体；不同蚕品种对硒的应答效益存在显著差异。本项目拟筛选出硒敏感和耐受蚕品种（即富硒蚕品种），用不同蚕品种开展硒调控家蚕的生长发育的研究，明确硒调控家蚕的生化和代谢过程，阐明合适浓度的硒促进家蚕生长发育的机理；明确高浓度硒情况下家蚕富硒的机理。项目的实施，对于丰富硒的生物学效应的理论和应用具有重要的意义；为开发富硒蚕蛹提供理论基础，对实现家蚕的多元化利用及开展特色蚕品种选育具有重要的支撑作用。

The biological effects of selenium have been studied in plants, mammals and medicine. Silkworm is a typical economic model insect; however, the biological benefits of selenium in silkworm have not been reported to now. Our previous results using P50 as model showed that after supplement of 25 μ m selenium could increase the weight of silkworm significantly, prolong the larval stage significantly, increase the total cocoon quantity and pupal weight significantly, but no effects on the pupal stage. The larvae of Bombyx mori have the ability of selenium enrichment, and the enrichment capacity of different tissues is spermary (ovary) > head > midgut ≈ silk gland > epidermis > fat body. There are significant differences in response to selenium of different silkworm varieties. In this project, selenium sensitive and tolerant silkworm varieties (i.e. selenium rich silkworm varieties) will be selected. We plan to investigate the effects of selenium on the growth and development of the silkworm using different silkworm varieties, to clarify the biochemical and metabolic processes of the silkworm regulated by selenium, to identify the key signal pathway of selenium regulating the development time of the silkworm. We plan to clarify the mechanism of selenium enrichment of the silkworm under high concentration of selenium treatment. The results of present projection are of great significance to the theory and application of the biological benefits of selenium enrichment, which will provide theoretical basis for the development of selenium rich silkworm chrysalis, and play an important supporting role in realizing diversified utilization of silkworm and developing special silkworm breeding.