Key factors influencing fate and activity of bacterial inoculants and their effect on the indigenous microbial community in the rhizosphere

影响细菌接种剂命运和活性的关键因素及其对根际本土微生物群落的影响

• 批准号: 132402322
• 负责人: Dr. Rita Grosch
• 金额: --
• 依托单位: Leibniz-Institut für Gemüse- und Zierpflanzenbau (IGZ) e.V.
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2013-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/132402322?language=en
• 关键词: Key; factors; influencing; fate; activity

The use of antagonistic bacteria could be an environmentally friendly altemative to protect plants from soil-borne pathogens if the rhizosphere competence and biocontrol efficiency of the antagonists would be more predictable. In this project, we aim to test the hypothesis that the soil type and plant species influence the rhizosphere competence and biocontrol efficiency of inoculant strains. Vice versa the structural diversity of the indigenous microbial community in the rhizosphere might be affected by the inoculation either directly or indirectly due to the interaction of the inoculant with the plant, which might result in changes of the root morphology and exudation patterns, with potential impact on the rhizosphere competence of the inoculants. Amongst a collection of in vitro antagonists towards Rhizoctonia solani previously tested under growth chamber and field conditions, two strains (Pseudomonas jessenii RU47 and Serratia plymuthica 3Re4-18) repeatedly showed a remarkable ability to reduce disease symptoms and severity of bottom rot disease on lettuce caused by R. solani AG 1-IB. Both model strains produce several factors potentially contributing to their bio-control activity, which at least in the latter strain are quorum sensing regulated. Whereas strain RU47 colonized only the root surface of lettuce, strain 3Re4-18 was also detected inside of the root tissue. The unique experimental setup at the field site of the Institute of Vegetable and Ornamental Crops (IGZ) in Großbeeren will enable us to test the influence of soil types on the rhizosphere competence (lettuce) of both antagonists at the same site under field conditions. In the third year the colonizing ability and the antagonistic performance of both strains will be tested on lettuce and potato. Growth chamber experiments with DsRed-tagged strains will be performed to assess how the colonization patterns, the root morphology and the exudation patterns are influenced by the soil type and the plant species. A polyphasic approach comprising advanced methods will be used to unravel the complex Interactions between inoculant strains, the pathogen, the indigenous microbial community and the plant.

如果拮抗剂的根际能力和生物防治效率更可预测，那么使用拮抗细菌可能是一种环境友好的替代方案，可以保护植物免受土传病原体的侵害。在这个项目中，我们的目的是检验土壤类型和植物物种影响接种菌株的根际能力和生物防治效率的假设。反之亦然，由于接种剂与植物的相互作用，根际本土微生物群落的结构多样性可能会直接或间接地受到接种的影响，这可能导致根部形态和渗出模式的变化，从而对接种剂的根际能力产生潜在影响。在先前在生长室和田间条件下测试的一系列针对立枯丝核菌的体外拮抗剂中，两种菌株（杰氏假单胞菌 RU47 和普城沙雷氏菌 3Re4-18）反复显示出显着的能力，可以减轻由立枯丝核菌 AG 1-IB 引起的生菜疾病症状和底部腐烂病的严重程度。两种模型菌株都会产生几种可能有助于其生物防治活性的因素，至少在后一种菌株中，这些因素受到群体感应的调节。菌株 RU47 仅定植于生菜的根表面，而菌株 3Re4-18 也在根组织内部检测到。大贝伦蔬菜和观赏作物研究所 (IGZ) 田间的独特实验装置将使我们能够在田间条件下测试同一地点土壤类型对两种拮抗剂根际能力（生菜）的影响。第三年将在生菜和马铃薯上测试两种菌株的定殖能力和拮抗性能。将使用 DsRed 标记菌株进行生长室实验，以评估土壤类型和植物物种对定植模式、根形态和渗出模式的影响。将采用由先进方法组成的多相方法来揭示接种菌株、病原体、本土微生物群落和植物之间复杂的相互作用。