Abstract：
Seed inoculation with entomopathogenic fungi (EPF) causes plant-mediated effects against arthropod herbivores, but the responses vary among EPF isolates. We used a wheat model system with three isolates representing Beauveria bassiana and Metarhizium spp. causing either negative or positive effects against the aphid Rhopalosiphum padi. Activities of six carbohydrate enzymes increased in plants showing biomass build-up after EPF inoculations. However, only aldolase activity showed positive correlation with R. padi numbers. Plants inoculated with M. robertsii hosted fewest aphids and showed increased activity of superoxide dismutase, implying a defense strategy of resistance towards herbivores. In M. brunneum-inoculated plants, hosting most R. padi, activities of catalase and glutathione reductase were increased suggesting enhanced detoxification responses towards aphids. However, M. brunneum simultaneously increased plant growth indicating that this isolate may cause the plant to tolerate herbivory. EPF seed inoculants may therefore mediate either tolerance or resistance towards biotic stress in plants in an isolate-dependent manner.
摘要：
用昆虫病原真菌（EPF）接种种子会引起植物对节肢动物草食动物的作用，但是EPF分离株的反应不同。我们使用了小麦模型系统，其中三个分离株代表球孢白僵菌和绿僵菌。对蚜虫Rhopalosiphumpadi产生负面或正面影响。在EPF接种后显示生物量积累的植物中，六种碳水化合物酶的活性增加。然而,只有醛缩酶活性与R.padi数呈正相关。接种M.robertsii的植物寄养了最少的蚜虫，并显示出增加的超氧化物歧化酶活性，暗示着一种抵抗食草动物的防御策略。在接种了M.brunneum的植物中，主持大多数R.padi,过氧化氢酶和谷胱甘肽还原酶的活性增加，表明对蚜虫的解毒反应增强。然而,Brunneum同时增加了植物的生长，表明该分离株可能导致植物耐受草食性。因此，EPF种子接种剂可以以分离株依赖性方式介导植物对生物胁迫的耐受性或抗性。
