开发和利用我国中草药作为储粮保护剂的研究——3、苦楝(Melia azedarach Linn )对绿豆象和赤拟谷盗毒杀作用机理的初步探讨

Study on the Development and Application of Chinese Medicinal Herbs as Stored-Grain Protectant III. The Preliminary Investigation into Poisoning Mechanism of Melia azedarach ( Linn. ) on Chinese Cowpea Weevil ( Collosobruchus chinesis L. ) and Red

本文初步探讨了苦楝对绿豆象成虫和赤拟谷盗各虫态的毒杀机理。利用点滴和拌粮等方法处理试虫,从个体和组织器官两个不同结构水平上,进行形态观察和组织学、组织化学检测。结果表明,苦楝粉95％乙醇提取物对试虫无明显毒杀作用:苦楝油对试虫有毒杀作用,可能是通过试虫的接触,经体壁进入体内,作用于神经系统,从而导致试虫的脱皮变态受阻而呈现畸形,直至试虫死亡。但其被检测的某些内部器官的组织学结构,无明显病变或异常。

The preliminary investigation into poisoning mechanism of Melia azedarach ( Linn. ) on Chinese cowpea weevil adults and different stages of red flour beetles has been carried out in this paper. Individual morphological observation, histological and histochemical examination have been made at two different structure levels: individual and tissue or organ after test insects were treated by topical applications and mixing with diet, etc.. The results show that 95% ethanal extract of Melia azedarach ( Linn. ) is ineffective against insects. The poisoning mechanism of seed oil of Melia azedarach ( Linn. ) is based on its penetrating of the test insect cuticle and acting on neural system. Then, the larval molting is markedly inhibited and pupation is prevented. This would lead to morphological distoration of the test insects and their death at last. But histological structure of some observed internal organs does not become abnormal.