PDF(Pubmed)
Abstract：
(1) Background: The mycophagous mite, Tyrophagus putrescentiae, was found to feed on entomopathogenic fungi (EPF) in our previous experiments, which seriously impacted the culture and preservation of fungal strains. Therefore, it is necessary to investigate the biological characteristics of the occurrence and damage to EPF. (2) Methods: The mite\'s growth and development and feeding preference were surveyed by comparative culture and observation; also, optical and electronic microscopies were employed. (3) Results: T. putrescentiae could survive normally after being fed on seven EPF species, including Purpureocillium lilacinum, Marquandii marquandii, Cordyceps fumosorosea, Beauveria bassiana, Metarhizium flavoviride, Lecanicillium dimorphum, and Metacordyceps chlamydosporia. The first four fungi were the mite\'s favorites with their greater feeding amount and shorter developmental duration. Interestingly, the mite could also feed on Metarhizium anisopliae and Metarhizium robertsii, but this led to the mite\'s death. After feeding on M. anisopliae and M. robertsii, the mites began to die after 24 h, and the mortality rate reached 100% by 72 h. Observation under optical microscopy and scanning electron microscopy revealed that the conidia of M. anisopliae and M. robertsii adhered to the mite\'s surface, but there was no evidence of penetration or invasion. However, dissection observation indicated that the two Metarhizium species germinate and grow within the mite\'s digestive tract, which implies that Metarhizium generalists with broad-spectrum hosts and the production of destruxins have acaricidal activity toward the mycophagous mites.
摘要：
(1)研究背景:食虫螨,酪氨酸腐胺科，在我们之前的实验中发现以昆虫病原真菌（EPF）为食，严重影响了真菌菌株的培养和保存。因此,有必要研究EPF的发生和损害的生物学特性。（2）方法：通过比较培养和观察，调查了螨的生长发育和摄食偏好。采用光学和电子显微镜。（3）结果：腐殖质在饲喂7种EPF后可以正常存活。包括紫薇纯毛,MarquandiiMarquandii,虫草虫草，白僵菌,黄维利绿僵菌，双甲黄霉,和留虫草衣原体。前四种真菌是螨的最爱，它们的摄食量较大，发育持续时间较短。有趣的是,螨虫也可以以金氏绿僵菌和robertsii绿僵菌为食，但这导致了螨虫的死亡。在取食了斑马氏菌和罗伯茨氏菌之后，24小时后螨虫开始死亡，到72h死亡率达到100%。在光学显微镜和扫描电子显微镜下观察发现，斑马分生孢子和罗伯氏分生孢子粘附在螨表面，但没有渗透或入侵的证据.然而,解剖观察表明，两种绿僵菌在螨的消化道内发芽和生长，这意味着具有广谱寄主和产生解虫菌素的绿僵菌通才对食虫螨具有杀螨活性。
