氯化苦土壤消毒对三七种植后真菌群落组成及多样性的影响

Effects of Fumigation with Chloropicrin on Soil Fungal Composition and Diversity after Continuous Cropping of Panax notoginseng

三七是我国特有的名贵中药材,喜温暖而阴湿的环境,这种环境极易诱发其根腐病形成,导致连作障碍的发生。氯化苦是一种具有挥发性的土壤薰蒸剂,目前,采用其进行土壤消毒是防治三七土传病害的有效措施。本研究中,我们采用基于Illumina MiSeq平台的ITS高通量测序技术研究氯化苦消毒后三七种植地中土壤真菌群落组成、多样性的变化。结果表明,氯化苦消毒后的三七根际土壤与未消毒的根际土壤相比真菌群落组成、多样性存在明显差异,并且经氯化苦消毒后,常见的主要三七致病真菌镰刀菌属(Fusarium)占比出现极大下降,从消毒前的7.42%下降到消毒后的1.97%,而对三七生长有益的木霉属(Trichoderma)真菌占比则出现相对升高(从消毒前的14.70%增加到消毒后的23.45%)。这些结果表明氯化苦消毒在三七连作障碍的防治中可以影响真菌群落的结构和组成,导致病原菌和有益菌占比发生变化,这种变化对于三七种植地土壤环境的改善、菌群结构的平衡以及土壤微生态的自我修复具有重要意义。

Panax notoginseng is one of the most valuable traditional Chinese medicine,which usually grows under warm and humid environment and thus has high mortality in root rot caused by continuous cropping.Currently,soil fumigation with chloropicrin(CP)is an effective way to avoid this.In this study,ITS sequencing based on Illumina MiSeq platform was employed to analyze the structure and diversity of fungal community in the soil samples with or without CP fumigation.We found that fumigation with CP had a remarkable effect on the composition of soil fungal community.Especially,the relative abundance of harmful genera,for example,Fusarium,was significantly decreased from 7.42%to 1.97%,while the abundance of friendly genera,for example,Trichoderma,was remarkably increased from 14.70%to 23.45%.Our results provide new insights for CP fumigation in promoting self-reparation of soil microecosystem and controlling root rot in Panax notoginseng caused by disordered fungal community.