UPMC Paris 6, CNRS UMR 7618, Paris Cedex 05, France.
FEMS Microbiol Ecol. 2012 Jan;79(1):251-9. doi: 10.1111/j.1574-6941.2011.01214.x.
Arbuscular mycorrhizal fungi (AMF) are key determinants of plant interactions in ecosystems. Through their effects on competition, they are regulators of the structure of communities. Conversely, the composition of plant assemblages may also influence the AMF colonization dynamics of plant species. Here, we tested under in vitro culture conditions the effects of Medicago truncatula, a highly mycorrhizal plant species, and Silene vulgaris, a weakly mycorrhizal plant species, grown single (monospecies treatments) or in combination (bispecies treatment) on the colonization dynamics of the AMF Rhizophagus irregularis MUCL 43194. The seedlings were placed in a pre-established hyphal network developing from a mature M. truncatula mycorrhizal donor plant. Extraradical mycelium (ERM) and root colonization parameters as well as root morphology were measured over a period of 12 days. An increased ERM length, total root colonization and proportion of arbuscules were noted in the bispecies treatment. Conversely, the bispecies treatment seemed to have no effect on root growth. This study also demonstrated the suitability of the in vitro culture system for studying the interactions between AMF and host plants grown as mono- and bispecies combinations.
丛枝菌根真菌（AMF）是生态系统中植物相互作用的关键决定因素。通过对竞争的影响，它们是群落结构的调节者。相反，植物组合的组成也可能影响植物物种的 AMF 定殖动态。在这里，我们在体外培养条件下测试了高度菌根植物紫花苜蓿和弱菌根植物普通矢车菊单种（单种处理）或组合（双种处理）种植对丛枝菌根真菌 Rhizophagus irregularis MUCL 43194 定殖动态的影响。幼苗被放置在一个预先建立的从成熟的紫花苜蓿菌根供体植物发育而来的菌丝网络中。在 12 天的时间内测量了外生菌丝（ERM）和根定殖参数以及根系形态。在双种处理中，观察到 ERM 长度、总根定殖和丛枝比例增加。相反，双种处理似乎对根生长没有影响。本研究还证明了体外培养系统适合研究作为单种和双种组合种植的 AMF 和宿主植物之间的相互作用。
