The Breeding Of Silkworm Race And The Construction Of The Silkworm Fingerprints Based Of SSR Markers

The growing of mulberry, sericulture, filature and the weaving of silk are great inventions of Chinese people. They helped the spreading of traditional civilization of ancient China and contribute to the development of modern economy. The production of cocoon is the basic of the silk industry. And the quantity and quality of the cocoon and its science and technology content determine the development of the silk industry. If you want to strengthen the silk industry you have to do it from the headwater. It has been proved that it's a good choice to breed and popularize choiceness silkworm varieties. This will increase silkworm cocoon production and thus increase your income. It will cut down your investment, act rapidly, however, there will be more economic benefits.There are 4 kinds of geography system about silkworm (Bombyx mori), many zoology types and hundreds of varieties have been formed due to the long term natural selection and artificial breeding. Faced with such abundant silkworm varieties, we need to ascertain properties to protect them effectively, avoid repetition and missing. The trend appears that it needs to add DNA fingerprints when examine and approve some variety in the international alongside with the promotion of the criterion of the germplasm survey and the strengthening of consciousness for information property protection. The study of the fingerprints, phylogenetic system and molecular system development about silkworm germplasm resources using SSR molecular marker is useful for the examining and approval, protection, using, construction of the core germplasm and inheritance breeding of silkworm germplasm. The main study field is as follows.1. The breeding of Runhua X Zhenyue, a silkworm variety for both spring and autumn use.According to the demand of spring varieties for autumn use or fall races for spring breeding, we aim at breeding vigorous silkworm variety with excellent synthesis characters and steady product. We use both hybrid breeding and strain breeding to choose choiceness parent materials. After 2 years, we succeed in breeding a silkworm variety through 11 generations' selection and improvement, Runhua X Zhenyue, for both spring and autumn use. This variety has passed through the united appraisal of our lab and 3 different areas of the country 2 years' tackle the key problem. The result shows that cocooning ratio exceeds 95%. And the cocoon crop, cocoon shell weight and raw silk weight per 10 000 four-instar silkworm each increased by 5~15%, 10~20%, 15~ 20% compared with antitheses. The cocoon shell rate reaches 15~20% and cocoon filament length is about 1000~1300 m. The reelability and raw silk percentage of cocoon each reaches 75~88%, 19~21% and neatness is about 94~96 cents. All of the economic and technical indexes reach the Country's criterion. The variety is able to bear high temperature, vigorous, easy to feed and has fluoride resistance. And it is uniform to hatch, molt and maturate. The silk is excellent, the quantity of cocoon crop is great and the propagation coefficient is high. It is fit both Yangtse Rive Valley and Yellow River Valley for all year round breeding. The variety passed through the fifth meeting of examining and approval of Examining and Approval Committee of the Northern Sericulture Science Research Cooperation Area and earned the authorization to popularize in these areaes.