Xu Lihui, Shang Qinghua, Nicolaisen Mogens, Zeng Rong, Gao Shigang, Gao Ping, Song Zhiwei, Dai Fuming, Zhang Jingze
Institute of Eco-Environmental Protection, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China.
Shanghai Key Laboratory of Protected Horticultural Technology, Shanghai 201403, China.
Microorganisms. 2025 Jan 2;13(1):68. doi: 10.3390/microorganisms13010068.
Phytopathogenic Jagger causes lettuce drop, a destructive soil-borne disease. As potential biocontrol agents for this disease, 2 of 31 bacterial strains isolated from soil samples from fields containing Jagger were identified using in vitro antagonistic assays against Jagger. Bioactivity experiments showed that Bac20 had higher inhibitory activity against Jagger than Bac45. Based on 16S rRNA sequences and phylogenetic analysis of a combination of sequences from , , , , and , Bac20 and Bac45 were identified as and , respectively. Lipopeptide compounds produced by each strain were identified using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) analysis. Both strains produced three types of lipopeptides, namely surfactins, iturins, and fengycins, whereas Bac20 showed the strongest intensity in its production of iturins, more than that of Bac45. Bac20 inhibited oxalic acid formation in early-stage lettuce leaves infected with Jagger, delaying pathogen infestation. Greenhouse experiments for controlling lettuce drop demonstrated that inoculation with Bac20 controlled lettuce drop by 71.7%. In conclusion, this study revealed that Bac20 has high potential for use as a biocontrol agent for controlling the lettuce drop caused by Jagger.
植物病原真菌贾格尔氏菌会导致生菜萎蔫病，这是一种具有破坏性的土传病害。作为该病害的潜在生物防治剂，从含有贾格尔氏菌的田间土壤样本中分离出的31株细菌菌株中的2株，通过对贾格尔氏菌的体外拮抗试验进行了鉴定。生物活性实验表明，Bac20对贾格尔氏菌的抑制活性高于Bac45。基于16S rRNA序列以及对来自……、……、……、……和……的序列组合进行系统发育分析，Bac20和Bac45分别被鉴定为……和……。使用基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）分析鉴定了每个菌株产生的脂肽化合物。两种菌株都产生了三种类型的脂肽，即表面活性素、伊枯草菌素和丰原素，而Bac20在伊枯草菌素的产生方面表现出最强的强度，超过了Bac45。Bac20抑制了感染贾格尔氏菌的生菜早期叶片中草酸的形成，延缓了病原菌的侵染。控制生菜萎蔫病的温室实验表明，接种Bac20可使生菜萎蔫病的发病率降低71.7%。总之，本研究表明Bac20具有作为生物防治剂控制由贾格尔氏菌引起的生菜萎蔫病的巨大潜力。
