Research On The Key Factor Of Triangle Mussel (Hyriopsis Cumingii) Bread Pearl

In order to research who take a major role on the effect of pearl-bread by the triangle mussel (Hyriopsis cumingii), we are divided into three parts. Part 1, The characteristics of Hyriopsis cumingii; Part 2, the density of alga in freshwater; Part 3, The density of suspended environment.Through contrast the shape of wild Hyriopsis cumingii and Pear-bread Hyriopsis cumingii, we have got the following result in part 1. When we bread pearl man-made, not only changed its figure, but also affect's growing speed, and its weight, height, shell length are all higher than wild Hyriopsis cumingii. Moreover, we have further confirmed the shell length, weight and length are the main factor, which effect pearl-bread by Hyriopsis cumingii.To investigate to best quantity of alga in part 2, we have controlled the transparence of water by giving fertilizer by man, then, we are known that it is the direct proportion among transparence, alga's density & moisture content. And, we also known it has best productivity of pearl-bread when transparent in 15cm-30cm, have good productivity when alga's density in 200,000/ml or moisture content in 210g/m3, Furthermore, its best production period is about five months, then, it can production 7.89g pearl per lpcs mussel,8.30g per 2pcs mussels,6.85g per 3pcs mussels.We have designed different quantity mussels suspended for pearl-bread in part 3, for example, it can stay 28,000pcs/hm2 for age 1 mussel,17,000pcs/hm2 for age 2 mussel, 21,000pcs/hm2 for age 3 mussel,17,000pcs/hm2 for age 4 mussel. Therefore, based on the output of pearl, it could not allow too low density during bread, it should be about 17,000pcs mussel/hm2.