Swarming motility plays the major role in migration during tomato root colonization by Bacillus subtilis SWR01
Swarming motility plays the major role in migration during tomato root colonization by Bacillus subtilis SWR01
复制标题
枯草芽孢杆菌 SWR01 在番茄根部定植期间，蜂群运动在迁移中起主要作用
DOI：
10.1016/j.biocontrol.2016.03.011
复制
发表时间：
2016-07-01
影响因子：
4.2
通讯作者：
Gao, Xuewen
中科院分区：
文献类型：
--
作者：
Gao, Shengfeng;Wu, Huijun;Gao, Xuewen
植物根际定殖是植物根际促生菌（PGPR）应用的重要环节。以前，趋化性被认为是殖民的主要特征。然而，由于趋化性缺陷突变体通常在同一时间的群集受损，在这项研究中，我们澄清了群集运动和趋化性在番茄根定殖枯草芽孢杆菌SWR 01所发挥的作用。用B处理番茄种子。在Simons' gnotobiotic系统中接种前，先将枯草杆菌SWR 01或突变体接种到土壤中，2周后观察其在根尖的定殖效果。显微镜观察和平板计数均表明，群集缺陷型和趋化性完善型突变体（Delta swrA、Delta minJ和Delta srfAC）的定殖效率约为亲本菌株SWR 01的5%-15%，而群集正常型和趋化性受损型突变体Delta cheV的定殖效率为野生型细菌的78.9%。这些结果表明，虽然趋化性和群集运动是重要的根定殖，和群集发挥的作用大于趋化性。此外，非鞭毛突变体（Delta hag）显示相对于B的0.47%的定殖效率。subtilis SWR 01，表明超过99%的根定殖需要鞭毛的存在。本研究为提高PGPR根际定殖提供了新的途径，具有一定的农业应用价值。(C)2016 Elsevier Inc. All rights reserved.
Root colonization is important for the application of Plant Growth-Promoting Rhizobacteria (PGPR). Previously, chemotaxis was believed to be the major trait for colonization. However, because chemotaxis defective mutants are usually swarming impaired at the same time, in this study we clarified the roles played by swarming motility and chemotaxis in tomato root colonization by Bacillus subtilis SWR01. Tomato seeds were treated with B. subtilis SWR01 or mutants before being sown in Simons' gnotobiotic system, and the colonization efficacy at root tips were observed after 2 weeks. Both microscopy and plate counts showed that the colonization efficacy of swarming defective and chemotaxis proficient mutants (Delta swrA, Delta minJ and Delta srfAC) was about 5%-15% that of the parental strain SWR01, while the colonization efficacy of the swarming normal and chemotaxis impaired mutant Delta cheV was 78.9% that of the wild-type bacteria. These results demonstrate that while both chemotaxis and swarming motility are important in root colonization, and the role played by swarming is greater than that of chemotaxis. In addition, non-flagellated mutants (Delta hag) showed 0.47% colonization efficacy relative to that of B. subtilis SWR01, suggesting more than 99% root colonization requires the presence of flagella. This study indicates new ways to enhance PGPR rhizoplane colonization, which is useful in agricultural applications. (C) 2016 Elsevier Inc. All rights reserved.