海南和西双版纳植胶区橡胶树根际真菌群落多样性分析

【目的】探讨不同气候区的植胶区橡胶树根际真菌群落组成和多样性差异以及环境因子相关性,为橡胶林高效种植管理及增产提质提供理论参考。【方法】以海南和西双版纳植胶区橡胶树为研究对象,通过提取橡胶树根际土壤样品的DNA,采用高通量测序技术研究分析两地橡胶树根际真菌的物种组成、多样性特征及主要驱动因子,并对其进行功能预测。【结果】海南和西双版纳在门水平和属水平上根际真菌组成及群落结构存在差异,西双版纳的担子菌门(Basidiomycota)相对丰度高于海南,但其子囊菌门(Ascomycota)和被孢霉门(Mortierellomycota)的相对丰度低于海南。降雨量和铵态氮(AN)对海南橡胶树根际真菌群落组成变异的解释率最高,速效钾(AK)和全钾(TK)对西双版纳橡胶树根际真菌群落组成变异的解释率最高。优势菌门中,子囊菌门与土壤有机质(SOM)呈显著负相关(P<0.05,下同),担子菌门与SOM呈正相关被孢霉门与SOM、AK呈显著负相关。在OTU水平上,海南植胶区橡胶树根际真菌的Shannon指数高于西双版纳,差异极显著(P<0.01);两地橡胶树根际真菌的β多样性差异不显著(P>0.05);海南植胶区橡胶树根际真菌的γ多样性更大。海南橡胶林根际真菌中内生菌—凋落物腐生菌—土壤腐生菌(Endophyte-litter saprotroph soil saprotroph)、真菌寄生菌(Fungal parasite)和菌根真菌(Arbuscular mycorrhizal)的相对丰度明显高于西双版纳橡胶林根际真菌。【结论】土壤理化性质是影响橡胶树根际真菌的最主要原因,西双版纳的SOM高于海南,从而导致西双版纳担子菌门相对丰度较高,子囊菌门较低,且西双版纳的AK也高于海南,故西双版纳的被孢霉门相对丰度也较低。

Diversity analysis of rhizosphere fungal communities of rubber trees in rubber plantation area of Hainan and Xishuangbanna

【Objective】To explore composition and diversity of the rhizosphere fungal communities of rubber trees in different climatic regions,and their correlation with environmental factors,so as to provide theoretical references for efficient plantation management and yield improvement of rubber forests.【Method】Rubber trees in Hainan and Xishuangbanna were taken as research objects. DNA was extracted from rhizosphere soil samples of rubber plantations and species composition,diversity,and main driving factors of rhizosphere fungi were analyzed by high-throughput sequencing technology,and their functions were predicted.【Result】Composition and community structure of rhizosphere fungi were different at phylum level and genus level between Hainan and Xishuangbanna. Relative abundance of Basidiomycota in Xishuangbanna was higher than that in Hainan,but relative abundance of Ascomycota and Mortierellomycota was lower than those in Hainan. Rainfall and ammonium nitrogen(AN)had the highest interpretation rate for the variation of the rhizosphere fungal community composition of rubber trees in Hainan,and available potassium(AK)and total potassium(TK)had the highest interpretation rate for the variation of rhizosphere fungal community composition of rubber trees in Xishuangbanna. Among the dominant phyla,ascomycetes were negatively correlated with soil organic matter(SOM)(P<0.05,the same below),while basidiomycetes were positively correlated with SOM. Mortierellaomycota showed a significant negative correlation with SOM and AK. At the OTU level,the Shannon index of rhizosphere fungi of rubber trees in the Hainan rubber plantation area was higher than that in Xishuangbanna,and the difference was extremely significant(P<0.01);β diversity of rhizosphere fungi of rubber trees in the two areas was not significantly different(P>0.05);γ diversity of rhizosphere fungi of rubber trees in Hainan rubber plantation area was greater. Abundance of Endophyte-litter saprotroph soil saprotroph,Fungal parasite,and Arbuscular mycorrhizal in the rhizosphere fungi of rubber forest in Hainan was significantly higher than that of rhizosphere fungi of rubber forest in Xishuangbanna. 【Conclusion】Physical and chemical properties of soil are the main factors affecting rhizosphere fungi of rubber trees. SOM of Xishuangbanna is higher than that of Hainan,resulting in a higher relative abundance of Basidiomycota and lower Ascomycota in Xishuangbanna,and the AK of Xishuangbanna is also higher than that of Hainan,so the relative abundance of Mortierellomycota in Xishuangbanna is also lower.