Metarhizium is widely recognized as an insect pathogenic fungus but it can also form symbiotic associations with plant roots. Here we assessed root rhizoplane, as well as endophytic colonization in monocots and dicots by ten Metarhizium strains representing species with either narrow or broad insect host ranges, as well as a related endophytic and nematophagous fungus, Pochonia chlamydosporia. In addition, insect pathogenicity of these strains was evaluated against mealworm (Tenebrio molitor), wax moth (Galleria mellonella) larvae and grasshoppers (Melanoplus sanguinipes). We found that all Metarhizium strains and Pochonia colonized the rhizoplane and rhizosphere of roots with varying degrees on all plants assessed. All Metarhizium strains tested showed a preference for endophytic colonization of monocot plants (within 20 d) when compared to dicots. While generalists showed pathogenicity towards all tested insect hosts, the specialists showed pathogenicity only towards grasshoppers, whereas Pochonia was avirulent towards insects. We observed variation in ability to colonize the rhizosphere amongst Metarhizium species. However, regardless of whether the Metarhizium species was a generalist or specialist insect pathogen, all strains tested retain ancestral ability to associate with plant roots.

根腐病被广泛认为是一种病原性真菌，但它也可以与植物根形成共生联系。在这里，我们通过10根评估根面，以及在单子叶植物和双子叶植物内生殖绿僵表示与任一窄或宽的昆虫宿主范围，以及一个相关的内生和食线虫真菌，物种菌株Pochonia chlamydosporia。此外，评估了这些菌株对粉虫（Tenebrio molitor），蜡蛾（Galleria mellonella）的幼虫和蚱（（Melanoplus sanguinipes）的致病性。我们发现，所有的绿僵菌菌株和Pochonia在所评估的所有植物上，根部的根际和根际定植在不同的程度。与双子叶植物相比，所有测试的Metrahizium菌株均显示出对单子叶植物的内生菌落定植（20 d内）。通才对所有测试的昆虫宿主均显示出致病性，而专家仅对蚱s显示出致病性，而Pochonia对昆虫没有致病性。我们观察到了在Metarhizium物种中根际定殖能力的变化。但是，无论后生菌属是普通病还是特殊昆虫病原体，所有测试的菌株都具有与植物根部结合的祖先能力。