Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Nanjing, 210014, PR China.
Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Nanjing, 210014, PR China; College of Horticulture and Plant Protection, Yangzhou University, Yangzhou, 225009, China.
Microbiol Res. 2021 Jan;242:126624. doi: 10.1016/j.micres.2020.126624. Epub 2020 Oct 15.
Colletotrichum fructicola, is an important fungal pathogen that has been reported to cause pear (Pyrus) anthracnose in China, resulting in substantial economic losses due to severe defoliation and decreased fruit quality and yield. In the search for novel strategies to control pear anthracnose, Lysobacter strains have drawn a great deal of attention due to their high-level production of extracellular enzymes and bioactive metabolites. In the present study, we compared four Lysobacter strains including Lysobacter enzymogenes OH11, Lysobacter antibioticus OH13, Lysobacter gummosus OH17 and Lysobacter brunescens OH23 with respect to their characteristics and activity against pear anthracnose caused by C. fructicola. The results showed that the evaluated Lysobacter species presented various colony morphologies when cultured on different media and were proficient in producing protease, chitinase, cellulase and glucanase, with L. enzymogenes OH11 showing typical twitching motility. L. enzymogenes OH11 and L. gummosus OH17 showed potent activity against the tested fungi and oomycetes. L. gummosus OH17 produced HSAF (heat-stable antifungal factor) which was demonstrated to be a major antifungal factor in L. enzymogenes OH11 and C3. Furthermore, L. antibioticus OH13 and L. brunescens OH23 exhibited strong antibacterial activity, especially against Xanthomonas species. Cultures of L. enzymogenes OH11 protected pear against anthracnose caused by C. fructicola, and the in vivo results indicated that treatment with an L. enzymogenes OH11 culture could decrease the diameter of lesions in pears by 35 % and reduce the severity of rot symptoms compared to that observed in the control. In the present study, we systemically compared four Lysobacter strains and demonstrated that they have strong antagonistic activity against a range of pathogens, demonstrating their promise in the development of biological control agents.
胶孢炭疽菌是一种重要的真菌病原体，在中国已被报道可引起梨炭疽病，严重落叶和降低果实品质和产量，造成巨大的经济损失。在寻找控制梨炭疽病的新策略时，由于其高水平地产生胞外酶和生物活性代谢物，Lysobacter 菌株引起了极大的关注。在本研究中，我们比较了包括 Lysobacter enzymogenes OH11、Lysobacter antibioticus OH13、Lysobacter gummosus OH17 和 Lysobacter brunescens OH23 在内的四种 Lysobacter 菌株，以评估它们对抗由胶孢炭疽菌引起的梨炭疽病的特性和活性。结果表明，评估的 Lysobacter 物种在不同培养基上培养时表现出不同的菌落形态，并且擅长产生蛋白酶、几丁质酶、纤维素酶和葡聚糖酶，其中 Lysobacter enzymogenes OH11 表现出典型的蠕动运动。Lysobacter enzymogenes OH11 和 Lysobacter gummosus OH17 对测试的真菌和卵菌具有强大的活性。Lysobacter gummosus OH17 产生 HSAF（热稳定抗真菌因子），该因子被证明是 Lysobacter enzymogenes OH11 和 C3 中的主要抗真菌因子。此外，Lysobacter antibioticus OH13 和 Lysobacter brunescens OH23 表现出强烈的抗菌活性，特别是对黄单胞菌属。Lysobacter enzymogenes OH11 培养物可保护梨免受胶孢炭疽菌引起的炭疽病，体内实验结果表明，与对照相比，用 Lysobacter enzymogenes OH11 培养物处理可使梨上的病斑直径减少 35%，并降低腐烂症状的严重程度。在本研究中，我们系统地比较了四种 Lysobacter 菌株，并证明它们对多种病原体具有强烈的拮抗活性，表明它们在开发生物防治剂方面具有潜力。
