生态学报2026，Vol.46Issue(2)：959-972,14.DOI:10.20103/j.stxb.202504250996
溶磷菌及其溶磷关键基因对紫花苜蓿耐盐性和盐渍土微生态的调控作用
Regulatory effects of phosphate-solubilizing bacteria AWH-NS6 and key gene pqqE on salt tolerance of Medicago sativa and the microecology of saline soil
摘要
Abstract
The enrichment of salt ions in saline soil can intensify the adsorption and precipitation of phosphate ions,resulting in the dual stress of ion toxicity and phosphorus deficiency on plants.Exploring and utilizing excellent phosphate-solubilizing bacteria(PSB)with salt tolerant characteristics from saline habitats is an effective approach to address plant phosphorus deficiency and salt stress damage in saline-alkali soils.This study utilized the highly efficient phosphate-solubilizing bacterium Serratia sp.AWH-NS6,isolated from the rhizosphere of Haloxylon ammodendron in saline desert habitats,as well as the constructed pqq E gene knockout mutant(related to organic acid secretion)and complementary strain to investigate the regulatory effects of pqq E gene mediated strain AWH-NS6 on the growth and salt tolerance of alfalfa(Medicago sativa)in saline-alkali soils from the Yellow River irrigation area of Ningxia via pot experiment.The results showed that the application of wild-type and complementation strain significantly improved the growth of alfalfa(plant height,root length and biomass)and enhanced nutrient uptake(nitrogen,phosphorus and potassium)compared to control treatment.Meanwhile,inoculation with wild-type,mutant and complementation strains significantly enhanced plant antioxidant enzyme activity(SOD,POD,CAT),reduced malondialdehyde content,increased proline and soluble sugar accumulation to alleviate oxidative stress.Furthermore,the application of strain AWH-NS6 significantly decreased soil pH and salt content,increased organic matter and available phosphorus content and enhanced soil enzyme activity.The structure and composition of soil microbial communities were changed by these three strains,with wild-type and complementary strains promoting soil nitrogen and phosphorus cycling,resulting in a significant enrichment of phosphate-solubilizing functional bacterial groups such as Gemmatimonadetes and Planctomycetes.The above indicated that the key phosphate-solubilizing gene pqq E mediates the ability of Serratia sp.AWH-NS6 to alleviate the toxic effects of salt stress on alfalfa,improved soil nutrient status and key enzyme activity,and enhanced the soil microenvironment by enriching beneficial microorganisms in the rhizosphere,thereby promoting the growth and salt tolerance of alfalfa.关键词
溶磷关键基因/溶磷菌/紫花苜蓿/盐胁迫/土壤微生物群落Key words
key phosphate-solubilizing gene/phosphate-solubilizing bacteria/alfalfa/salt stress/soil microbial community引用本文复制引用
王博瑞,罗汶婧,马红彬,李慧萍..溶磷菌及其溶磷关键基因对紫花苜蓿耐盐性和盐渍土微生态的调控作用[J].生态学报,2026,46(2):959-972,14.基金项目
宁夏自然科学基金项目(2024AAC03141) （2024AAC03141）
国家自然科学基金项目(32402670) （32402670）
