四川大渡河流域不同地点铁杉林瓢虫科多样性比较

文章首次报道了四川大渡河流域的铁杉林瓢虫科种类、数量及发生时间。在3个地点的铁杉林中,共采集到瓢虫48种。对斑小瓢虫Scymnus geminus、华山松小瓢虫S.huashansong、马蹄毛瓢虫S.lycotropus、宁陕毛瓢虫S.ningshanensis为首次在四川报道。3月到11月均可采集到瓢虫成虫,以5月(22种)、6月(25种)和7月(24种)为最多。幼虫出现主要集中在5月。羊厂沟铁杉林是以阔叶为主的针阔混交林,其瓢虫的物种丰富度指数、多样性指数、均匀度指数均远远高于泥巴沟和驷马桥。泥巴沟和驷马桥同属于针叶树占优势的针阔混交林,林内瓢虫科物种丰富度指数较低,但种类优势度高。三地瓢虫组成相似性均处于较低水平。

In vitro SYNTHESIS OFα-AND β-ECDYSONES BY PROTHORACIC GLANDS OF Bombyx mori

Ⅰ. INTRODUCTION The prothoracic gland (PG) is one of the most vital endocrine organs in insects. It is the target organ of prothoracotropic hormone (PTTH) secreted by the neurosecretory cells of the brain. Some investigators have shown that the prothoracic gland is the