Molecular characterization of bacterial antibiosis in the rhizosphere and its impact on Solanaceous plant diseases

公众对在环境中使用化学农药和对某些疾病的化学防治措施无效的关注，加剧了对植物病原体生物防治的兴趣。已证明几种拮抗假单胞菌属。可以在体外或受控条件下使用植物病原体控制植物病原体种群。然而，在土壤中的微生物代谢的效率仍然是可变的，解释了为什么只有少数抗菌代谢产物产生假单胞菌属。菌株已经作为生物杀虫剂商业化。在这里，它建议两个茄科植物物种，马铃薯和番茄，被用来研究定制的抗菌代谢产物产生假单胞菌属的影响。接种抗两种重要的细菌性植物病原体：引起马铃薯普通疮痂病的疮痂链霉菌（Streptomyces scabiei（Ss））和Clavibacter michiganensis subsp. michiganensis（Cmm）引起番茄青枯病和溃疡病。本研究的总体目标是在分子水平上了解根际真菌是如何作用的，它如何影响Ss和Cmm的转录组学，它对病原体定殖和感染植物的影响，以及它如何保护植物免受疾病的侵害。假单胞菌属的集合。产生抗微生物代谢产物如吩嗪-1-羧酸（PCA）、2，4-二乙酰基间苯三酚（DAPG）和氰化氢（HCN）的菌株。也已经开发了这些不能产生抗微生物代谢物的菌株的敲除。这些生物体将用于解决以下具体目标：1）表征与假单胞菌属相关的转录活性。马铃薯和番茄根际抗菌代谢产物的产生及其对植物病害防治的影响。2)研究抗菌代谢物产生对Ss和Cmm转录组学的影响。3)确定是否抗菌代谢产物的生产，除了寄生，触发诱导的系统性耐药（ISR）在茄科。这项创新的工作应导致更好地了解如何假单胞菌-介导的植物病害在土壤条件下起作用，以及它如何有助于茄科植物的病害保护。

An increased interest in biocontrol of plant pathogens has been fuelled by public concern over the use of chemical pesticides in the environment and ineffective chemical control measures against certain diseases. It has been demonstrated that several antagonistic Pseudomonas spp. can control plant pathogen populations under in vitro or controlled conditions using antibiosis. However, the efficiency of antibiosis in soil is still variable, explaining why only few antimicrobial metabolite-producing Pseudomonas spp. strains have been commercialized as biopesticides. Here, it is proposed that two Solanaceous plant species, potato and tomato, be used to study the effect of tailored antimicrobial metabolite-producing Pseudomonas spp. inoculations against two important bacterial plant pathogens: Streptomyces scabiei (Ss) causing common scab of potato and Clavibacter michiganensis subsp. michiganensis (Cmm) causing bacterial wilt and canker of tomato. The general goal of this research is to understand, at the molecular level, how antibiosis operates in the rhizosphere, how it affects the transcriptomics of Ss and Cmm, its effect on colonization and infection of plants by pathogens, and how it can protect against diseases. A collection of Pseudomonas spp. producing antimicrobial metabolites such as phenazine-1-carboxylic acid (PCA), 2,4-diacetylphloroglucinol (DAPG) and hydrogen cyanide (HCN) has been isolated in our laboratory. Knockouts of these strains, incapable of producing the antimicrobial metabolites, have also been developed. These organisms will be used to address the following specific goals: 1) Characterize the transcriptional activity associated with Pseudomonas spp. antimicrobial metabolite production in the rhizosphere of potato and tomato and its impact on controlling plant diseases. 2) Study the impact of antimicrobial metabolite production on Ss and Cmm transcriptomics. 3) Determine if antimicrobial metabolite production can, in addition to antibiosis, trigger induced systemic resistance (ISR) in Solanaceae. This innovative work should lead to a better understanding of how Pseudomonas spp.-mediated antibiosis operates under soil conditions and how it can contribute to disease protection in Solanaceae.