混合菌剂对葡萄白粉病发生及叶际微生物多样性的影响

Effects of Mixed Fungicides on Occurrence of Grapevine Powdery Mildew and Microbial Diversity in Grapevine Phyllosphere

为明确常见杀菌剂及生防菌剂处理对葡萄白粉病发生及葡萄叶际微生物多样性的影响,进一步预测叶际微生物功能,采用随机取样法调查田间葡萄白粉病害,以Illumina高通量测序技术结合生物信息学分析了混合杀菌剂及生防菌剂处理的葡萄叶际微生物群落多样性差异,并结合PICRUSt2对微生物功能进行预测。结果表明,施用混合菌剂能显著降低白粉病的发生;混合菌剂处理后叶际细菌群落Chao1指数及Shannon指数分别下降了50.78%、48.57%;叶际真菌群落Chao1指数降低42.80%,Shannon指数增加了0.07。在门水平上,药剂处理后的优势细菌门为Firmicutes、Actinobacteriota,优势真菌门为Ascomycota和Basidiomycota;在属水平上,药剂处理后,相对丰度显著增加的细菌有Bacillus,真菌有Erysiphe和Aspergillus。葡萄叶际微生物群落功能预测,共评估了489条MetaCyc途径,以P<0.05、倍数变化FC>3进行筛选,共得到49条相关途径,其中有2条途径显著上调,47条显著下调,下调途径主要与葡萄核酸代谢、光呼吸、叶绿素、维生素合成等功能有关。

In order to clarify the effects of common fungicides and biocontrol agents on the occurrence of grapevine powdery mildew and grapevine foliar microbial diversity,and further predict the function of foliar microorganisms,random sampling method was used to investigate grapevine powdery mildew in the field,the differences of microbial community diversity between fungicide and biocontrol treatment were analyzed by Illumina high-throughput sequencing technology combined with bioinformatics,and the microbial function was predicted by PICRUSt2.The results showed that the application of mixed bacterial agents could significantly reduce the incidence of powdery mildew.Chao1 index and Shannon index of grapevine leaf bacterial community decreased by 50.78% and 48.57%,respectively;Chao1 index of foliar fungal community decreased by 42.80%,and Shannon index increased by 0.07.At the phylum level,the dominant bacteria phyla of pesticide treatment were Bacillota and Actinomycetota,and the dominant fungi phyla were Ascomycota and Basidiomycota.At the genus level,after pesticide treatment,the bacteria with significantly increased relative abundance were Bacillus,and the fungi with significantly increased abundance were Erysiphe and Aspergillus.In the prediction of grapevine leaf microbial community function,489 MetaCyc pathways were evaluated.Based on the screening of P<0.05 and Fold Change(FC)>3,and 49 related pathways were obtained,of which two were significantly up-regulated and 47 were significantly down regulated,which were mainly related to the functions of grapevine nuclear acid metabolism,photorespiration,chlorophyll and vitamin synthesis.