【摘要】 灭幼脲可影响东方粘虫蜕皮甾类滴度,并表现出如下特点:(1)强烈抑制末龄幼虫血淋巴蜕皮甾类滴度峰,并存在一定的剂量依赖关系,但对峰以外时间的滴度无影响;(2)点滴处理东方粘虫体壁后,灭幼脲以剂量依赖的方式抑制前胸腺的分泌活力,但却不抑制离体前胸腺分泌蜕皮酮;(3)灭幼脲抑制促前胸腺激素对前胸腺的活化。更多还原

【Abstract】 Diflubenzuron (DFB) seriously suppressed in a dose-dependent manner the ecdysteroid peak of sixth instar larvae. Topically applied 0.04μg DFB per larva to day-0 sixth instar larvae, the ecdysteroid peak was inhibited by approximately 75%.More detailed researches revealed that DFB did not inhibit isolatcd PG in vitro for synthesizing and/or secreting ecdysone. However, DFB suppressed in a dose-dependent manner the ability of PG in vivo test to secrete ecdysone. The results also indicated that the activation of day-2 PG by prothoracicotropic hormone (PTTH) was inhibited by DFB, causing that the ability of PG to secrete ccdysone was greatly suppressod. Because day-2 PG has acquired the competency to PTTH, the action of DFB was different from that of JH, which inhibited the activation of PG by suppressing its competency to PTTH.更多还原