Toral Laura, Rodríguez Miguel, Béjar Victoria, Sampedro Inmaculada
Xtrem Biotech S.L., European Business Innovation Center, Avenida de la Innovación, 1, Armilla, 18016 Granada, Spain.
Department of Microbiology, Faculty of Pharmacy, Campus de Cartuja s/n, 18071 Granada, Spain.
Microorganisms. 2020 Jul 3;8(7):992. doi: 10.3390/microorganisms8070992.
This study aims to evaluate the use of strain XT1 as a plant growth-promoting rhizobacterium (PGPR) and biocontrol agent against in tomato and strawberry plants. Foliar and radicular applications of strain XT1 increased plant total biomass as compared to the control and -infected plants, with root applications being, on the whole, the most effective mode of treatment. Applications of the bacterium were found to reduce infection parameters such as disease incidence and severity by 50% and 60%, respectively. We analyzed stress parameters and phytohormone content in order to evaluate the capacity of XT1 to activate the defense system through phytohormonal regulation. Overall, the application of XT1 reduced oxidative damage, while the HO and malondialdehyde (MDA) content was lower in XT1-treated and -infected plants as compared to non-XT1-treated plants. Moreover, treatment with XT1 induced callose deposition, thus boosting the response to pathogenic infection. The results of this study suggest that the signaling and activation pathways involved in defense mechanisms are mediated by jasmonic acid (JA) and ethylene hormones, which are induced by preventive treatment with XT1. The study also highlights the potential of preventive applications of strain XT1 to activate defense mechanisms in strawberry and tomato plants through hormone regulation.
本研究旨在评估菌株XT1作为植物促生根际细菌（PGPR）和生物防治剂对番茄和草莓植株上的[具体病害，原文未提及]的防治效果。与对照植株和感染[具体病害，原文未提及]的植株相比，菌株XT1的叶面和根部施用均增加了植物的总生物量，总体而言，根部施用是最有效的处理方式。发现施用该细菌可使感染参数如发病率和病情严重程度分别降低50%和60%。我们分析了胁迫参数和植物激素含量，以评估XT1通过植物激素调节激活防御系统的能力。总体而言，XT1的施用减少了氧化损伤，与未用XT1处理的植株相比，经XT1处理和感染[具体病害，原文未提及]的植株中过氧化氢（HO）和丙二醛（MDA）含量较低。此外，用XT1处理可诱导胼胝质沉积，从而增强对病原体感染的反应。本研究结果表明，防御机制中涉及的信号传导和激活途径由茉莉酸（JA）和乙烯激素介导，这些激素由XT1的预防性处理诱导产生。该研究还强调了菌株XT1通过激素调节在草莓和番茄植株中预防性激活防御机制的潜力。
