Posada-Vergara Catalina, Vidal Stefan, Rostás Michael
Agricultural Entomology, Department of Crop Sciences, University of Goettingen, Grisebachstr 6, 37077 Goettingen, Germany.
J Fungi (Basel). 2023 Jul 28;9(8):796. doi: 10.3390/jof9080796.
is a soil-borne fungal entomopathogen that can be associated with plant roots. Previous studies have demonstrated that root colonization by beneficial fungi can directly affect soil-borne pathogens through competition and antibiosis and can activate a systemic response in plants, resulting in a primed state for a faster and/or stronger response to stressors. However, the mechanisms by which inoculation ameliorates symptoms caused by plant pathogens are not well known. This study evaluated the ability of to protect oilseed rape ( L.) plants against the soil-borne pathogen and investigated whether the observed effects are a result of direct interaction and/or plant-mediated effects. In vitro and greenhouse experiments were conducted to measure fungal colonization of the rhizosphere and plant tissues, and targeted gene expression analysis was used to evaluate the plant response. The results show that delayed pathogen colonization of plant root tissues, resulting in decreased disease symptoms. Direct competition and antibiosis were found to be part of the mechanisms, as growth was stimulated by the pathogen and inhibited the in vitro growth of . Additionally, changed the plant response to the pathogen by locally activating key defense hormones in the salicylic acid (SA) and abscisic acid (ABA) pathways. Using a split-root setup, it was demonstrated that there is a plant-mediated effect, as improved plant growth and decreased disease symptoms were observed when was in the systemic compartment. Moreover, a stronger systemic induction of the gene suggested a priming effect, involving the SA pathway. Overall, this study sheds light on the mechanisms underlying the protective effects of against soil-borne pathogens in oilseed rape plants, highlighting the potential of this fungal entomopathogen as a biocontrol agent in sustainable agriculture.
是一种可与植物根系相关联的土传真菌性昆虫病原体。先前的研究表明，有益真菌在根部定殖可通过竞争和抗生作用直接影响土传病原体，并能激活植物的系统反应，从而使植物处于一种预处理状态，以便对压力源做出更快和/或更强的反应。然而，接种该菌减轻植物病原体所致症状的机制尚不清楚。本研究评估了该菌保护油菜（ ）植株免受土传病原体侵害的能力，并调查了所观察到的效果是否是直接相互作用和/或植物介导作用的结果。进行了体外和温室实验以测量根际和植物组织中的真菌定殖情况，并采用靶向基因表达分析来评估植物的反应。结果表明，该菌延迟了植物根组织中的病原体定殖，从而减轻了病害症状。发现直接竞争和抗生作用是其机制的一部分，因为病原体刺激了该菌的生长，而该菌在体外抑制了病原体的生长。此外，该菌通过局部激活水杨酸（SA）和脱落酸（ABA）途径中的关键防御激素，改变了植物对病原体的反应。采用分根设置证明存在植物介导作用，因为当该菌存在于系统区室时，观察到植物生长改善且病害症状减轻。此外，基因的更强系统诱导表明存在一种预处理效应，涉及SA途径。总体而言，本研究揭示了该菌对油菜植株中土传病原体具有保护作用的潜在机制，突出了这种真菌性昆虫病原体作为可持续农业中生物防治剂的潜力。
