摘要
[目的]探究马铃薯块茎蛾取食胁迫对马铃薯根际细菌群落结构与多样性的影响,系统解析"植物—害虫—根际微生物"互作效应,为筛选和利用马铃薯根际有益微生物提供参考依据.[方法]在室内以盆栽马铃薯品种合作88为试验材料,对马铃薯苗期、块茎形成期、淀粉积累期和成熟期4个生育期根际细菌组成结构及多样性进行分析,同时于马铃薯苗期第5枝侧枝伸长时接种马铃薯块茎蛾3龄幼虫取食胁迫处理,处理与对照(CK)分别于12、24、36和48 h时采集根际土壤,通过Mothur对4个生育期及苗期不同取食胁迫时间和对照的马铃薯根际细菌群落进行α多样性分析和主成分分析;基于细菌16S rRNA序列相似性对丰度排名前20的菌株进行序列比对并构建系统发育进化树及功能预测.[结果]马铃薯成熟期根际细菌物种ACE和Chao1指数显著(P<0.05,下同)高于其他3个时期.马铃薯块茎蛾取食胁迫后,马铃薯根际细菌群落主要优势菌门排序为放线菌门>变形菌门>绿弯菌门>酸杆菌门>厚壁菌门,其中放线菌门相对丰度在胁迫12、24、36、48 h时分别增加7.91%、26.54%、21.56%和2.97%,取食胁迫增加了变形菌门和拟杆菌门的相对丰度,降低了酸杆菌门的相对丰度;在属水平上,取食胁迫后,马铃薯根际细菌节杆菌属相对丰度在胁迫后12、24、36和48 h时较CK分别增加137.39%、113.58%、93.12%和61.87%,取食胁迫增加了鞘氨醇单胞菌属的相对丰度,降低了norank_f_norank_0_Vicinamibacterales和norank_f_VicinamibacterACEae的相对丰度.主成分分析结果表明马铃薯根际细菌微生物对照组和处理组明显分离;系统发育进化树结果显示相对丰度前20的菌株隶属于放线菌门、绿弯菌门、厚壁菌门、酸杆菌门和芽单胞菌门;COG注释的功能分类有24个,其中氨基酸转运和代谢功能最为富集.[结论]马铃薯块茎蛾取食胁迫引起马铃薯根际细菌群落结构及相对丰度发生变化,其中放线菌门节杆菌属细菌相对丰度变化最为显著.
Abstract
[Objective]To explore the effects of Phthorimaea operculella(Zeller)feeding stress on the community structure and diversity of potato rhizosphere bacteria,and to systematically analyze the interaction effect of"plant-pest-rhizosphere microorganisms",so as to provide a reference for the screening and utilization of potato rhizosphere benefi-cial microorganisms.[Method]In the laboratory,the composition and diversity of rhizosphere bacteria in four growth stages,including potato seedling stage,tuber formation stage,starch accumulation stage and maturity stage,were ana-lyzed using potted potato variety Cooperation 88 as experimental materials.At the same time,the 3rd instar larvae of P.operculella were inoculated at the elongation of the 5th lateral branch at the potato seedling stage,and the rhizosphere soil in treatment and control(CK)was collected at 12,24,36 and 48 h,respectively,and the α diversity analysis and principal component analysis were carried out by Mothur on the potato rhizosphere bacterial communities at four growth stages,and different feeding stress times and control at seedling stage.Based on the similarity of bacterial 16S rRNA se-quences,the top 20 strains in abundance were compared with each other,and phylogenetic evolutionary trees and func-tional predictions were constructed.[Result]The ACE and Chao1 indexes of rhizosphere bacterial species at potato matu-rity stage were significantly higher(P<0.05,the same below)than those at the other three stages.After the feeding stress of P.operculella,the main dominant bacteria in the potato rhizosphere bacterial community were in the order of Actino-mycetes>Proteobacteria>Chloromyticus>Acidobacteria>Firmicutes,the relative abundance of Actinomycetes increased by 7.91%,26.54%,21.56%and 2.97%at 12,24,36 and 48 h,respectively,and feeding stress increased the relative abundance of Proteobacteria and Bacteroidetes,decreased the relative abundance of Acidobacter.At the genus level,the relative abundance of Arthrobacter spp.increased by 137.39%,113.58%,93.12%and 61.87%compared with CK at 12,24,36 and 48 h after feeding stress,respectively,feeding stress increased the relative abundance of Sphingomonas spp.,and decreased the relative abundance of norank_f_norank_0_Vicinamibacterales and norank_f_VicinamibacterACEae.The results of principal component analysis showed that potato rhizosphere bacteria of the control group and the treatment group were greatly separated.The phylogenetic tree results showed that the top 20 strains in relative abundance belonged to Actinomycetes,Crucidomycetes,Firmicutes,Acidobacteria and Blastomonas.There were 24 functional categories of COG annotation,among which amino acid transport and metabolism were the most enriched.[Conclusions]The commu-nity structure and relative abundance of potato rhizosphere bacteria change due to feeding stress of P.operculella,among which the relative abundance of Arthrobacter spp.of Actinomycetes changes the most significantly.
基金项目
国家自然科学基金(31760519)
国家重点研发计划课题(2021YFD1400705)
国家科技期刊平台
NSTL
万方数据