干旱区研究2023，Vol.40Issue(12)：1938-1948,11.DOI:10.13866/j.azr.2023.12.07
科尔沁沙地水盐处理对油莎豆农田土壤细菌群落及植株生理特性的影响
Effects of irrigation and salinity treatments on the soil bacterial community and plant physiological characteristics of Cyperus esculentus farmland in Horqin Sandy Land
摘要
Abstract
To reveal the soil bacterial community structure and its effects on Cyperus esculentus,affected by different irrigation and salinity treatments in the Qian Gorlos Irrigation District,a random plot sampling experiment was conducted using two-factor,three-level(irrigation level:50%,70%,and 100%standard irrigation quota;salt level:control group,mild salinity stress,and moderate salinity stress).Comparative analysis of soil bacterial community characteristics in C.esculentus cropland under different irrigation and salinity treatments was performed.Simultaneously,the molecular ecological network of soil bacteria was constructed to determine the keystone species and its interrelationship with C.esculentus growth.Results showed that(1)The dominant phyla of soil bacteria in C.esculentus cropland were Proteobacteria(22.85%±3.80%),Acidobacteriota(20.02%±3.21%),and Actinobacteriota(18.85%±2.41%).The dominant genera were RB41,Sphingomonas,and Rubrobacter.Bacterial alpha diversity differed insignificantly under different irrigation or salinity treatments(P>0.05).With increasing irrigation,the relative abundance of Proteobacteria gradually increased,whereas that of RB41 gradually decreased.The same trend was observed with increasing salinity stress.(2)The co-existence relationship between bacterial species was stronger in 100%standard irrigation quota treatments,with a positive correlation rate of 78.05%.Additionally,the degree of interactions and tightness of connections between bacterial species was highest at 50%standard irrigation quota treatments.The highest ecological network complexity and degree of interactions among bacterial communities were found in control group soils,and stronger co-existence relationships among bacterial species were found in moderate salinity soils,with a positive correlation rate of 75.31%.(3)The number of keystone species increased with increasing irrigation.Additionally,the RB41 genus appeared under 70%and 100%standard irrigation quota treatments.Significant differences were observed in keystone species under different salinity stresses.At an S2 salinity gradient,the number of keystone species reached a maximum,with the emergence of the dominant genera RB41 and Lysobacter.The keystone species were Rubrobacter,RB41,Dongia,Steroidobacter,Nitrospira,Lysobacter,and Luteolibacter.(4)Variations in irrigation significantly affected plant height,crown size,number of tillers,above-ground dry weight,carboxylase activity,proline,and superoxide dismutase activities of C.esculentus plants(P<0.05).Changes in salt application significantly affected plant height,above-ground dry weight,abscisic acid,soluble sugar,peroxidase activity,and malondialdehyde in C.esculentus(P<0.05).The final screening was performed to conclude that Lysobacter,Nitrospira,Lysobacter,Dongia,RB41,Steroidobacter,and Luteolibacter were significantly associated with the growth and physiological traits of C.esculentus(P<0.05).The soil bacterial community composition,molecular network,and keystone species were changed as a result of different irrigation or salt treatments,and keystone species were significantly associated with the growth of C.esculentus.This improved information contributes to a better understanding of the soil bacterial community structure and its ecological function in C.esculentus cropland and provides a theoretical basis for adaptive planting and stable and high yield of C.esculentus.关键词
水盐处理/细菌群落结构/关键菌种/共现网络/油莎豆/科尔沁沙地Key words
irrigation or salinity treatments/bacterial community structure/keystone species/co-occurrence net-work/Cyperus esculentus/Horqin Sandy Land引用本文复制引用
吴蕊,曹红雨,高广磊,于明含,丁国栋,张英,赵珮杉..科尔沁沙地水盐处理对油莎豆农田土壤细菌群落及植株生理特性的影响[J].干旱区研究,2023,40(12):1938-1948,11.基金项目
国家重点研发计划项目"沙漠化土地油沙豆适沙抗旱耐盐品种选育与适应性机制研究"(2019YFC0507601) （2019YFC0507601）
