中华绒螯蟹（Eriocheir sinensis）是我国十分重要的淡水养殖品种,然而在河蟹的养殖过程中出现了普遍发生一龄蟹性早熟现象,严重影响了......

The brown planthopper,Nilaparvata lugens (St?l), is the most serious insect pest of rice. It has developed high resistan......