家蚕翅原基的一些发育规律研究

Study on the Development of the Silkworm Wing Discs

为进一步解明家蚕的生长发育机制 ,调查了家蚕 5龄幼虫及蛹期翅原基的大小和形态变化 :翅原基在 5龄前期生长缓慢 ,变态前生长最快 ,2～ 3d及 8～ 11d为形态变化最大的两个时期 ;蛹期翅芽基本不变 ,3d始见初生鳞毛 ,5d时已经呈浓密的毛状 ,8d时翅面鳞毛发育成柳叶状 ,之后逐渐出现分叉 ,9d花纹清晰可见 ,化蛾后翅面鳞片呈现棕榈叶状。进行翅原基摘除和异位移植发现 :4个翅原基全部摘除后家蚕仍能正常生长并发育成蛹和具有交配及产卵能力的蛾 ,表明家蚕血球和造血器官有很强的再生能力 ,家蚕血球细胞的生成可能具有更复杂的机制 ,由此证明了家蚕翅原基异位移植的可行性。

We investigated the development of the wing discs in size and form during 5 th instar larval and pupal period. We found that the wing disc growth was slow in the prophase of the larva, while reach a peak just before metamorphism. 2 d to 3 d and 8 d to 11 d during 5 th instar were two obvious period of wing discs morphogenesis. We also found that pupa was a perfecting period of the wing buds, with a little change of the size. We could find firstborn scales on the wing buds of 3 d pupa and hairy scales on 5 d pupa's. Squamas on the surface of 8 d pupal wing buds presented a willow-leaf-like shape and then palm-like shape on moth wings'. A primary study on wing disc exclusion and exo-transplantation to abdomen was carried out. The results showed that silkworm could grow and develop to pupa and moth with the ability of mating and ovipositing, even when all of the wing discs were extirpated. From these we concluded that the hemocytes or hemopoietic organs perhaps had a very strong rebirth competence, viz. the mechanism of the hemopoietic function might be more abstruse than we have known today. The feasibility of the silkworm wing discs growing and developing in exotic site was proved by transplantation technique.