桑蚕制种相关（Silkworm seed production）.docVIP

桑蚕制种相关（Silkworm seed production） Requirements for silkworm breeding A careful and far sighted breeding plan should be formulated according to silk production and marketing needs, silk scientific and technological level, silkworm species status and breeding level, etc.. Requirements for silkworm sericulture production, is a molting, a hatch, a mounting, cocoon number of rearing silkworm head number, the unit with the highest amount of mulberry silk production. Requirements for silkworm cocoon silk production, the car is high, the rate of the wire, reelability, high uniformity and good purity, and less, micro degumming loss rate is low, especially in the automatic reeling machine and high-speed shuttleless loom is widely used, for the reelability performance, and the strength of the silk cocoon higher requirements. As for the problem of fine denier silk in silk production, in addition to a small number of special needs, generally do not require more fine size, while the demand is the size variation is small, such as 20 / 22D (7-8 cocoon general), is a 20 22D difference 2D, 40 / 44D is 4D, can be reduced to 1D and 2D, the smaller the better (the reason on the reeling by reeling solution). Of course, the long season of sericulture has different requirements due to the different climate, and the silkworm species used in spring are focused on the quality of cocoon, silk and silk. General requirements of cocoon layer rate above 25%, filament length of more than 1400m, Reelability and neatness good. In summer and autumn silkworm variety, in the strong vitality of the premise, and strive to improve the cocoon silk cocoon. In the late autumn silkworm varieties, than summer and autumn silkworm cocoon silk and its high volume. For the basic silkworm species, we should focus on the future, and reserve breeding materials for the purpose of greatly improving the level of silkworm breeds. The general requirement is that the individual characters are outstanding, while the general c