多化性蚕品种“广农三号”(“秋303”ד137”一代杂交种)自1977年育成推广后,由于强健、发育齐一,担桑产值高,丝质比较优良,深受农村及丝厂的欢迎。但由于“秋303”原种体弱难养,没有黑种(滞育卵),繁制7、8、9月用种非常困难,单产低,蚕种成 The variety “Guangnong 3” (“autumn 303” × “137” generation hybrids), which was promoted and popularized in 1977, is characterized by its strong growth, homogeneous development, high yield and high silk quality. Rural and silk factory welcome. However, due to “303 autumn” the original species is weak and difficult to support, there is no black species (diapause eggs), breeding in July, August and September is very difficult to use, low yield, silkworm into