不同覆膜处理下藠头根际土壤真菌群落的响应特征

Response characteristics of fungal communities in Allium chinense rhizosphere soil under different mulching treatments

【目的】探讨不同覆膜措施对藠头根际土壤真菌群落结构、生态功能和物种间相互作用的影响,以期为生产上地膜的使用与选择提供理论依据和数据支持。【方法】在藠头收获期采集覆盖普通透明地膜、蓝色地膜以及不覆膜处理下的藠头根际土壤,利用高通量测序技术,并结合FUNGuild数据库、分子生态网络等分析方法对各处理下根际土壤真菌群落进行研究。【结果】覆膜处理降低了真菌群落多样性,但在蓝色地膜处理下富集了相对丰度更高的腐质霉属(Humicola)、篮状菌属(Talaromyces)、曲霉属(As⁃pergillus)等有益真菌菌群;从真菌分子生态网络可以看出,地膜覆盖虽使网络变得简化,但真菌群落对外部环境的抵抗能力有所提高,其中蓝色地膜较普通地膜表现更为稳定;此外,对各处理的真菌群落进行功能预测后发现,腐生型功能菌群的相对丰度在蓝色地膜下占比更高,促进了有机物的分解和养分循环。【结论】藠头根际土壤的真菌群落结构、生态功能和物种间相互关系在不同覆膜处理下表现出显著差异,其中,蓝色地膜处理下的真菌群落更有利于藠头的生长发育,但同时也应考虑覆膜措施引起病原型功能菌群的增加可能带来的潜在风险。

【Objective】The present paper aimed to explore the effects of different mulching measures on fungal community structure,ecologi⁃cal function and species interaction in rhizosphere soil of Allium chinense,in order to provide theoretical basis and data support for the use and selection of mulching film for production.【Method】At the harvest period of A.chinense,rhizosphere soil covered with ordinary transparent film,blue film and no film treatment was collected,and the fungal community in the rhizosphere soil under each treatment was studied using high⁃throughput sequencing technology,FUNGuild database,molecular ecological network and other analytical methods.【Result】The mulching treatment reduced the diversity of fungal communities,but under the blue mulching treatment,beneficial fungal communities such as Humicola,Talaromyces and Aspergillus with higher relative abundance were enriched;From the molecular ecological network of fungi,it could be seen that although plastic film coverage simplified the network,the resistance of fungal communities to the external environment had been improved,with blue plastic film exhibiting more stability than ordinary plastic film;In addition,after functional prediction of the fungal communities in each treatment,it was found that the relative abundance of saprophytic functional microbial communities was higher under blue plastic film,promoting the decomposition of organic matter and nutrient cycling.【Conclusion】The fungal community structure,ecologi⁃cal functions,and species relationships in the rhizosphere soil of A.chinense show significant differences under different film covering treatments.Among them,the fungal community under blue film covering treatment is more conducive to the growth and development of A.chinense,but at the same time,the potential risks caused by the increase of pathogenic functional bacterial communities caused by film covering measures should also be considered.