在二化性桑蚕杂交种的生产与供应中,春用种的来源,可分为春制越年春用种和秋制越年春用种两大部分。近年来,虽然有不少地区尽量扩大秋制越年春用种的生产量,但由于春季养蚕制种,具有气温适宜、叶质较好、对交批发育较易调节、蚕作较安全等优点,绝大部分蚕区,春制种的质量,仍较秋制种为优。然而,作为春制春用种,也有 In the production and supply of hybridized silkworm hybrids, the sources of spring planting can be divided into two major parts: the spring growing spring and the growing spring autumn growing spring. In recent years, although there are many areas try to expand the annual production of autumn planting more species, but due to the spring sericulture, with suitable temperature, leaf quality is better, more willing to regulate the development of cross-breeding, silkworms for safer Advantages, most of the sericulture area, the quality of spring seed, still superior to the autumn plant species. However, it is also used as spring-spring planting