Xing Yanhong, Zhang Pingliang, Zhang Wenming, Yu Chenxu, Luo Zhuzhu
College of Resources and Environmental Sciences, Gansu Agricultural University, Lanzhou, China.
Dryland Agriculture Institute, Gansu Academy of Agricultural Sciences, Lanzhou, China.
Front Microbiol. 2024 Jan 5;14:1318586. doi: 10.3389/fmicb.2023.1318586. eCollection 2023.
For potato production, continuous cropping (CC) could lead to autotoxicity buildup and microflora imbalance in the field soil, which may result in failure of crops and reduction in yield. In this study, non-targeted metabolomics (via liquid chromatography with tandem mass spectrometry (LC-MS/MS)) combined with metagenomic profiling (via high-throughput amplicon sequencing) were used to evaluate correlations between metabolomics of potato root exudates and communities of bacteria and fungi around potato plants to illustrate the impacts of CC. Potato plants were grown in soil collected from fields with various CC years (0, 1, 4, and 7 years). Metabolomic analysis showed that the contents and types of potential autotoxins in potato root exudates increased significantly in CC4 and CC7 plants (i.e., grown in soils with 4 and 7 years of CC). The differentially expressed metabolites were mainly produced via alpha-linolenic acid metabolism in plant groups CC0 and CC1 (i.e., no CC or 1 year CC). The metabolomics of the groups CC4 and CC7 became dominated by styrene degradation, biosynthesis of siderophore group non-ribosomal peptides, phenylpropanoid biosynthesis, and biosynthesis of various plant secondary metabolites. Continuous cropping beyond 4 years significantly changed the bacterial and fungal communities in the soil around the potato crops, with significant reduction of beneficial bacteria and accumulation of harmful fungi. Correlations between DEMs and microflora biomarkers were established with strong significances. These results suggested that continuous cropping of potato crops changed their metabolism as reflected in the plant root exudates and drove rhizosphere microflora to directions less favorable to plant growth, and it needs to be well managed to assure potato yield.
对于马铃薯生产而言，连作（CC）会导致田间土壤中自毒物质积累和微生物群落失衡，这可能致使作物歉收和产量下降。在本研究中，非靶向代谢组学（通过液相色谱-串联质谱法（LC-MS/MS））结合宏基因组分析（通过高通量扩增子测序）被用于评估马铃薯根系分泌物的代谢组学与马铃薯植株周围细菌和真菌群落之间的相关性，以阐明连作的影响。马铃薯植株种植于从具有不同连作年限（0、1、4和7年）的田间采集的土壤中。代谢组学分析表明，在连作4年和7年的植株（即种植于连作4年和7年土壤中的植株）中，马铃薯根系分泌物中潜在自毒物质的含量和种类显著增加。差异表达代谢物主要通过CC0和CC1组（即无连作或连作1年）植物中的α-亚麻酸代谢产生。CC4和CC7组的代谢组学以苯乙烯降解、铁载体类非核糖体肽的生物合成、苯丙烷类生物合成以及各种植物次生代谢物的生物合成为主。连作超过4年显著改变了马铃薯作物周围土壤中的细菌和真菌群落，有益细菌显著减少，有害真菌积累。建立了差异表达代谢物（DEMs）与微生物群落生物标志物之间的显著相关性。这些结果表明，马铃薯作物的连作改变了其根系分泌物中所反映的代谢，使根际微生物群落朝着不利于植物生长的方向发展，需要进行妥善管理以确保马铃薯产量。
