Above-Belowground Interactions Group, Institute of Biology, Leiden University, P.O. Box 9505, 2300 RA Leiden, The Netherlands.
Natural Products Laboratory, Institute of Biology, Leiden University, P.O. Box 9505, 2300 RA Leiden, The Netherlands.
FEMS Microbiol Ecol. 2024 Sep 14;100(10). doi: 10.1093/femsec/fiae116.
Plant-associated microorganisms can negatively influence plant growth, which makes them potential biocontrol agents for weeds. Two Gammaproteobacteria, Serratia plymuthica and Pseudomonas brassicacearum, isolated from roots of Jacobaea vulgaris, an invasive weed, negatively affect its root growth. We examined whether the effects of S. plymuthica and P. brassicacearum on J. vulgaris through root inoculation are concentration-dependent and investigated if these effects were mediated by metabolites in bacterial suspensions. We also tested whether the two bacteria negatively affected seed germination and seedling growth through volatile emissions. Lastly, we investigated the host specificity of these two bacteria on nine other plant species. Both bacteria significantly reduced J. vulgaris root growth after root inoculation, with S. plymuthica showing a concentration-dependent pattern in vitro. The cell-free supernatants of both bacteria did not affect J. vulgaris root growth. Both bacteria inhibited J. vulgaris seed germination and seedling growth via volatiles, displaying distinct volatile profiles. However, these negative effects were not specific to J. vulgaris. Both bacteria negatively affect J. vulgaris through root inoculation via the activity of bacterial cells, while also producing volatiles that hinder J. vulgaris germination and seedling growth. However, their negative effects extend to other plant species, limiting their potential for weed control.
植物相关微生物可能会对植物生长产生负面影响，这使它们成为杂草的潜在生物防治剂。两种从入侵杂草普通豚草（Jacobaea vulgaris）根部分离出的革兰氏阴性菌，粘质沙雷氏菌（Serratia plymuthica）和野油菜黄单胞菌（Pseudomonas brassicacearum），会抑制其根系生长。我们研究了通过根部接种，这两种细菌对普通豚草的影响是否与浓度有关，并探究了这些影响是否由细菌悬浮液中的代谢物介导。我们还测试了这两种细菌是否通过挥发性排放物对种子萌发和幼苗生长产生负面影响。最后，我们研究了这两种细菌对其他 9 种植物的宿主特异性。两种细菌在根部接种后均显著降低了普通豚草的根系生长，粘质沙雷氏菌在体外表现出浓度依赖性模式。两种细菌的无细胞上清液均不影响普通豚草的根系生长。两种细菌均通过挥发性物质抑制普通豚草的种子萌发和幼苗生长，表现出不同的挥发性特征。然而，这些负效应并非针对普通豚草特异的。两种细菌通过根部接种和细菌细胞的活性对普通豚草产生负面影响，同时产生抑制其种子萌发和幼苗生长的挥发性物质。然而，它们的负效应会扩展到其他植物物种，限制了它们作为杂草防治剂的潜力。
