黄顶菊与3种本地植物竞争对丛枝菌根真菌种类和多样性的影响

【目的】外来植物黄顶菊对生态环境和农业经济造成了严重危害,了解黄顶菊与3种不同本地植物种植生长对丛生菌根(AM)真菌群落结构和多样性造成的影响,可以从土壤微生物角度进一步解释黄顶菊的入侵机制。【方法】通过同质园小区试验模拟黄顶菊入侵的生态进程,以黄顶菊和3种本地植物狗尾草、藜、黄香草木樨为研究对象,采用AM真菌的形态学鉴定方法,研究黄顶菊与3种本地植物不同种植方式对AM真菌群落结构和多样性的影响。【结果】(1)黄顶菊根际土壤聚集的AM真菌种类与其伴生本地植物种类有关:黄顶菊与狗尾草混种处理中优势种为网状球囊霉和根内球囊霉,而黄顶菊分别与藜、草木樨混种处理中优势种均为网状球囊霉、根内球囊霉和缩球囊霉;(2)黄顶菊分别与狗尾草和黄香草木樨混种处理中AM真菌种类既高于本地单种处理,也高于黄顶菊单种处理,说明随着黄顶菊的入侵和地上植物多样性的改变,AM真菌种类也发生改变;(3)与3种本地植物单种相比,黄顶菊各混种处理和黄顶菊单种处理中黄顶菊根际土壤根内球囊霉的重要值均增加,表明黄顶菊入侵有利于根内球囊霉的生长和发育。【结论】黄顶菊入侵改变了根际土壤AM真菌的群落结构和多样性,AM真菌的改变既与本地植物种类有关,也与入侵程度有关。

Effects of Flaveria bidentis grown with three native plants on species and diversity of arbuscular mycorrhizal fungi

Aim] The alien plant Flaveria bidentis can do serious damage to the environment and agricultural production. Understanding the effects of planting growth between F. bidentis and three native plants on the community structure and diversity of arbuscular mycorrhizal fungi (AMF) can further help understand of its impact on soil microorganisms.Method] An experiment of growth of F. bidentis with one of three native plants, Setaria viridis, Chenopodium album and Melilotus officinalis, was performed in a common garden. Arbuscular mycorrhizal fungi were collected from the rhizosphere soil of F. bidentis or native plants and identified using morphological characteristics. It''s used to comparatively study the effects of F. bidentis and three kinds of native plants on the community structure and diversity of AMF when they grew in different pattern.Result] The AMF species accumulated in the rhizosphere of F. bidentis were related to their concomitant native plant species. The dominant species when F. bidentis was grown with S. viridis were Glomus reticulatum and Rhizophagus intraradices, while when grown with C. album or with M. officinalis, Glomus reticulatum, R. intraradices and Septoglomus constrictum dominated. The AMF species in the mixed treatments of F. bidentis and S. viridis, F. bidentis and M. officinalis were higher than that in the native single treatment and single treatment of F. bidentis, suggesting that the types of AMF changed with the invasion of F. bidentis and the diversity of above-ground plant species. Compared with the three species of native plants, the Important Value of R. intraradices in the rhizosphere of F. bidentis increased in both the single and mixed treatments of F. bidentis, indicating that the presence of F. bidentis is beneficial to the growth and development of R. intraradices.Conclusion] The presence of F. bidentis can influence the AMF community structure and diversity in its rhizosphere soil. Native plants present in the community and level of invasions can also influence AMF community.