Abstract

Cinnamomum migao plants often face different degrees of drought in karst habitats, which can lead to plants’ death, especially in the seedling stage. Widespread of arbuscular mycorrhizal (AM) fungi in karst soils have the potential to address this drought, which is a threat to C. migao seedlings. We inoculated C. migao seedlings with spores from Glomus lamellosum and Glomus etunicatum, two AM fungi widely distributed in karst soils, to observe seedling growth response after simulated drought. Our results showed that 40 g of G. lamellosum and G. etunicatum significantly promoted the growth of C. migao seedlings, 120 days after inoculation. Following a 15-day drought treatment, root colonization of the seedlings with G. lamellosum or G. etunicatum had lower the accumulation of malondialdehyde (MDA) and increased the accumulation of enzymes and osmotic substances in the seedlings. The relative water content in different organs (roots, stems, and leaves) of the drought-stressed seedlings was higher in plants with G. lamellosum or G. etunicatum than in plants without AM fungi colonization. Our results showed that inoculation with AM fungi was an effective means to improve the drought resistance of C. migao seedlings.

摘要

米高肉桂在喀斯特栖息地经常面临不同程度的干旱，这会导致植物死亡，尤其是在苗期。岩溶土壤中广泛分布的丛枝菌根 (AM) 真菌有可能解决这种干旱，这对C. migao幼苗构成威胁。我们用来自Glomus lamellosum和Glomus etunicatum 的孢子接种C. migao幼苗，这两种 AM 真菌广泛分布于喀斯特土壤中，以观察模拟干旱后幼苗的生长反应。我们的结果表明，40 g G. lamellosum和G. etunicatum显着促进了C. migao的生长幼苗，接种后120天。经过 15 天的干旱处理，G. lamellosum或G. etunicatum幼苗的根部定植降低了丙二醛 (MDA) 的积累，并增加了幼苗中酶和渗透物质的积累。干旱胁迫幼苗不同器官（根、茎和叶）的相对含水量在有G. lamellosum或G. etunicatum的植物中高于没有 AM 真菌定植的植物。我们的结果表明，接种AM真菌是提高米高木苗抗旱性的有效手段。