稻飞虱体内的类酵母共生菌及其营养功能

Yeast like symbiotes and their nutritional function in rice planthoppers

类酵母共生菌(yeastlikesymbiotes,YLS)是稻飞虱体内的一种共生菌,存在于稻飞虱的脂肪体细胞中,出芽生殖,通过卵直接传给后代,其数量随飞虱的生长发育而增加,但对于单位鲜虫重而言,基本保持恒定;系统进化研究结果显示,YLS在分类上属于子囊菌亚门(Ascomycotina)、核菌纲(Pyrenomycetes),其基因组大小与自由生活的酵母菌类似;共生体系中YLS可能为宿主提供必需氨基酸、蛋白质和固醇类等营养物质。现代分子生物学技术的发展为深入研究稻飞虱和类酵母共生菌的相互关系提供了有利条件,可以从基因水平证明二者的相互依赖性。

Yeast like symbiotes（YLS） are one kind of intracellular symbiotes in rice planthoppers, They are found in the fat body cells, reproduce by budding, and are transmitted vertically from a mother to her progeny, The number of YLS increases as the host develops, while their number per μg of fresh wt, remains constant in the post-embryonic stages. The phylogenetic study indicates YLS are in the class Pyrenomycetes in the subphulum Ascomycotina. YLS is similar in genome size to yeast, YIS can supply essential amino acids, proteins, and sterols for development of planthoppers. By using modern molecular techniques, studies of the mutual relationship between rice planthoppers and YLS in the genetic level become possible.