Isolation, Identification, and Biocontrol Activity of Stress-Tolerant Bacillus Strains from Saline-Alkaline Soils

doi:10.16409/j.cnki.2095-039x.2026.02.015

Abstract

Abstract: To screen for microbial resources with both saline-alkaline tolerance and biocontrol potential, six Bacillus strains were isolated from the rhizosphere soil of halophytes in Xinjiang, China. Based on whole-genome sequencing(WGS) and taxonomic analyses, strains hST19, hST20, hST18, and hST16 were identified as Bacillus licheniformis, B. rugosus, B. swezeyi, and B. vallismortis, respectively. Notably, strains hST8 and hST9 exhibited distant phylogenetic relationships with known type strains, suggesting they are potential novel species. Environmental adaptability assays demonstrated that all isolates could grow under extreme conditions of 45℃, pH 10.0, and 10% NaCl. Specifically, strains hST8, hST9, hST16, hST18, and hST19 maintained normal growth even at pH 12.0, exhibiting significantly stronger saline-alkaline tolerance than several control biocontrol strains. Biocontrol efficacy evaluations revealed that strains hST8 and hST20 possessed antagonistic activity against phytopathogenic bacteria. Furthermore, strains hST20, hST9, hST16, and hST18 exhibited inhibitory effects against three fungal pathogens causing kiwifruit soft rot. Except for hST9, the volatile organic compounds(VOCs) produced by the isolates suppressed the growth of pathogenic fungi. In detached fruit assays, strains hST16 and hST18 effectively alleviated kiwifruit soft rot caused by Diaporthe actinidiae. In conclusion, the Bacillus strains isolated in this study possess both salt-alkali tolerance and multiple biocontrol traits, serving as promising candidate resources for the development of biocontrol agents in saline-alkaline agriculture.

Key words: Bacillus, salt-alkali tolerance, biocontrol activity, plant rhizosphere

CLC Number:

S476

XU Fugui, CUI Chuanbin, WANG Pingping, WANG Bingxin, QIAN Guoliang. Isolation, Identification, and Biocontrol Activity of Stress-Tolerant Bacillus Strains from Saline-Alkaline Soils[J]. Chinese Journal of Biological Control, 2026, 42(3): 720-728.

/ Recommend

References

[1] 常跃畅,葛亚军,曹占强.我国盐碱地分布特征及改良实践分析[J].农业灾害研究, 2025, 15(1):244-246.
[2] Zhu W, Gu S G, Jiang R, et al. Saline-alkali soil reclamation contributes to soil health improvement in China[J]. Agriculture, 2024, 14(8):1210.
[3] Liu L P, Long X H, Shao H B, et al. Ameliorants improve saline-alkaline soils on a large scale in northern Jiangsu Province, China[J]. Ecological Engineering, 2015, 81:328-334.
[4] Chen M M, Zhang S R, Liu L, et al. Combined organic amendments and mineral fertilizer application increase rice yield by improving soil structure, P availability and root growth in saline-alkaline soil[J]. Soil and Tillage Research, 2021, 212:105060.
[5] 金明姬,周妍宏,文波龙,等.石膏改良盐碱土研究进展[J].南京林业大学学报(自然科学版), 2023, 47(2):1-8.
[6] 赵维彬,王松,刘玲玲,等.生物炭改良盐碱地效果及其对植物生长的影响研究进展[J].土壤通报, 2024, 55(2):551-561.
[7] Liu Y, Shi A Q, Chen Y, et al. Beneficial microorganisms:regulating growth and defense for plant welfare[J]. Plant Biotechnology Journal, 2025, 23(3):986-998.
[8] Luo C H, He Y J, Chen Y P. Rhizosphere microbiome regulation:unlocking the potential for plant growth[J]. Current Research in Microbial Sciences,2025, 8:100322.
[9] An X C, Wang Z F, Teng X M, et al. Rhizosphere bacterial diversity and environmental function prediction of wild salt-tolerant plants in coastal silt soil[J]. Ecological Indicators, 2022, 134:108503.
[10] 陈兰,谢永丽,杨雪,等.干旱沙地白刺根际Bacillus halotolerans DGL6对“青麦7号”的促生及防病效果[J].微生物学通报, 2023, 50(9):3899-3911.
[11] 陈云云,李惠霞,张海英,等.萎缩芽胞杆菌MQ19ST15鉴定及对甘蓝枯萎病的盆栽防效[J].植物保护, 2021, 47(5):64-71.
[12] Lahlali R, Ezrari S, Radouane N, et al. Biological control of plant pathogens:a global perspective[J]. Microorganisms, 2022, 10(3):596.
[13] Bonaterra A, Badosa E, Daranas N, et al. Bacteria as biological control agents of plant diseases[J]. Microorganisms, 2022, 10(9):1759.
[14] 梁翔宇,顾欣,刘文辉,等.盐碱地盐生植物根际耐盐促生菌的筛选及鉴定[J].农业科学研究, 2021, 42(4):1-6, 11.
[15] Lin L, Xu K W, Shen D Y, et al. Antifungal weapons of Lysobacter, a mighty biocontrol agent[J]. Environmental Microbiology, 2021, 23(10):5704-5715.
[16] Laborda P, Zhao Y Y, Ling J, et al. Production of antifungal p-aminobenzoic acid in Lysobacter antibioticus OH13[J]. Journal of Agricultural and Food Chemistry, 2018, 66(3):630-636.
[17] Fabian B K, Foster C, Asher A J, et al. Elucidating essential genes in plant-associated Pseudomonas protegens Pf-5 using transposon insertion sequencing[J]. Journal of Bacteriology, 2021, 203(7):e00432-20.
[18] Luo Y W, Luo L, Huang X J, et al. Characterization and metabolic pathway of Pseudomonas fluorescens 2P24 for highly[J]. Bioresource Technology,2023, 382:129189.
[19] Fan B, Wang C, Song X F, et al. Bacillus velezensis FZB42 in 2018:the Gram-positive model strain for plant[J]. Frontiers in Microbiology, 2018, 9:2491.
[20] Zhao W S, Ban Y Y, Su Z H, et al. Colonization ability of Bacillus subtilis NCD-2 in different crops and its effect[J]. Microorganisms, 2023, 11(3):776.
[21] Xie Q B, Lao G S, Fang, Y K, et al. Investigating polyhydroxyalkanoate synthesis for insights into drug resistance in Xanthomonas oryzae pv. oryzae[J].International Journal of Molecular Sciences, 2025, 26(4):1601.
[22] Ma C, Liu W, Du X F, et al. The flavonoid metabolic pathway genes Ac4CL1, Ac4CL3 and AcHCT1 positively[J]. Plant Molecular Biology, 2025, 115(1):21.
[23] Souza D P, Oka G U, Alvarez-Martinez C E, et al. Bacterial killing via a type IV secretion system[J]. Nature Communications, 2015, 6:6453.
[24] 苏文文,罗英,李苇洁,等.贵州省猕猴桃果实病害鉴定及病原菌生物学特性研究[J].中国南方果树, 2025, 54(1):164-172.
[25] Li L, Pan H, Chen M Y, et al. Isolation and identification of pathogenic fungi causing postharvest fruit rot of kiwifruit(Actinidia chinensis)in China[J].Journal of Phytopathology, 2017, 165:782-790.
[26] Fu J H, Liu Y W, Liu X C, et al. Screening of saline-alkali tolerant microorganisms and their promoting effects on rice growth under saline-alkali stress[J].Journal of Cleaner Production, 2024, 481:144176.
[27] 卜凡,韩思宁,朱仁贵,等.一株耐盐碱多黏类芽孢杆菌TaRb44的分离鉴定和耐盐促生作用评价[J].微生物学报, 2025, 65(4):1498-1511.
[28] 周萍,王赤恒,仇剑波,等.贝莱斯芽孢杆菌6W1挥发性有机物对禾谷镰刀菌的抑菌抑毒作用[J].微生物学通报, 2024, 51(9):3484-3496.
[29] 王静,曹建敏,陈德鑫,等.短小芽孢杆菌AR03挥发性有机物的抑菌活性及其组分分析[J].中国农业科学, 2018, 51(10):1908-1919.