南方农业学报2024，Vol.55Issue(4)：942-953,12.DOI:10.3969/j.issn.2095-1191.2024.04.004
连作木薯对土壤理化性质及细菌群落演替的影响
Effects of continuous cropping of cassava on soil physicochemi-cal properties and bacterial community succession
摘要
Abstract
[Objective]The aim of this study was to investigate how continuous cropping of cassava affected the physi-cochemical properties of non-rhizosphere and rhizosphere soils,as well as the succession of bacterial communities,and thus providing a theoretical basis for understanding the formation of cassava continuous cropping obstacles.[Method]The cassava variety South China 205 was continuously cultivated in an abandoned field for three years.The soil were sampled at cassava root tuber maturity stage(250 d after planting)in each year.Combining soil agrochemical analysis,high-throughput sequencing technology and bioinformatics methods,effects of continuous cassava on non-rhizosphere and rhi-zosphere soil physicochemical properties and bacterial group succession were studied.[Result]The results showed that pH,organic matter,alkali-hydrolyzed nitrogen and available phosphorus contents of non-rhizosphere and rhizosphere soil of cassava were decreased and urease activity was increased in two and three years of continuous cropping compared with the first year of planting,and except available phosphorus content,the changes of other indexes reached significant level(P<0.05,the same below).Continuous cropping of cassava led to a decrease in the diversity and richness of soil bacterial communities.However,the decline rate in rhizosphere soil bacterial communities was slower than that in non-rhizosphere soils.There were significant differences in the classification and phylogenetic Beta diversity of non-rhizosphere and rhizo-sphere soil bacterial communities of continuous cropping cassava.The dominant bacterial phyla in non-rhizosphere and rhi-zosphere soils were Actinobacteriota,Proteobacteria,Chloroflexi,Firmicutes and Acidobacteriota.The main dominant bac-terial genera were Bacillus,norank_f_Roseiflexaceae,norank_f_norank_o_Vicinamibacterales and norank_f_norank_o_Gaiellales.At the operational taxonomic unit(OTU)level,significant or extremely significant(P<0.01)differences were found in the composition of soil bacterial communities in non-rhizosphere and rhizosphere soils of cassava at different con-tinuous cropping years.The structure of soil bacterial communities was mutually affected by soil physicochemical proper-ties,the environmental factors affected bacterial community ranked as alkaline hydrolysis nitrogen content>organic mat-ter content>pH>available phosphorus content>urease activity.[Conclusion]Continuous cropping can lead to changes in non-rhizosphere and rhizosphere soil physicochemical properties,bacterial community diversity and richness,and soil physicochemical properties and bacterial community structure of cassava greatly deteriorate in the third year of continuous cropping.Soil physicochemical properties are correlated to structure of bacterial communities at certain extent.Notably,the decrease in the abundance of beneficial bacteria might be an important reason for the deterioration of soil bacterial community succession caused by cassava continuous cropping.关键词
木薯/连作/非根际土壤/根际土壤/细菌群落Key words
cassava/continuous cropping/non-rhizosphere soil/rhizosphere soil/bacterial community分类
农业科技引用本文复制引用
彭晓辉,黎亮武,欧桂宁,黄苑航,彭晓雪,阳太亿,甘李,申章佑,韦茂贵..连作木薯对土壤理化性质及细菌群落演替的影响[J].南方农业学报,2024,55(4):942-953,12.基金项目
国家自然科学基金项目(31960389,31860347) National Natural Science Foundation of China(31960389,31860347) （31960389,31860347）
