Institute of Biochemistry and Genetics, Ufa Federal Research Centre, Russian Academy of Sciences, Prospekt Oktyabrya, 71, 450054 Ufa, Russia.
Biomolecules. 2022 Feb 10;12(2):288. doi: 10.3390/biom12020288.
Endophytic plant-growth-promoting microorganisms can protect plants against pathogens, but they have rarely been investigated as potential biocontrol agents and triggers of induced systemic resistance (ISR), regulated by phytohormones, against viruses. We studied the role of endophytic strains 26D and Ttl2, which secrete ribonucleases and phytohormones, in the induction of tomato plant resistance against potato virus X and potato virus Y in a greenhouse condition. The endophytes reduced the accumulation of viruses in plants, increased the activity of plant ribonucleases and recovered the fruit yield of infected tomato plants. Both the 26D and Ttl2 strains induced ISR by activating the transcription of genes related to salicylate- and jasmonate-dependent responses. The 26D and Ttl2 strains increased the content of cytokinins and decreased the level of indolacetic acid in plants infected with PVX or PVY. PVY led to an increase of the abscisic acid (ABA) content in tomato plants, and PVX had the opposite effect. Both strains reduced the ABA content in plants infected with PVY and induced ABA accumulation in plants infected with PVX, which led to an increase in the resistance of plants. This is the first report of the protection of tomato plants against viral diseases by foliar application of endophytes.
内生植物促生微生物可以保护植物免受病原体的侵害，但它们作为潜在的生物防治剂和植物激素调节的诱导系统抗性（ISR）的触发因子，对抗病毒的研究很少。我们研究了内生菌株 26D 和 Ttl2 的作用，它们分泌核糖核酸酶和植物激素，在温室条件下诱导番茄植株对马铃薯 X 病毒和马铃薯 Y 病毒的抗性。内生菌减少了病毒在植物中的积累，提高了植物核糖核酸酶的活性，并恢复了感染番茄植物的果实产量。26D 和 Ttl2 菌株通过激活与水杨酸和茉莉酸依赖反应相关的基因的转录来诱导 ISR。26D 和 Ttl2 菌株增加了感染 PVX 或 PVY 的植物中细胞分裂素的含量，并降低了吲哚乙酸的水平。PVY 导致番茄植物中脱落酸（ABA）含量增加，而 PVX 则有相反的作用。这两种菌株都降低了感染 PVY 的植物中的 ABA 含量，并诱导了感染 PVX 的植物中 ABA 的积累，从而提高了植物的抗性。这是首次报道通过叶面施用内生菌来保护番茄植物免受病毒病的侵害。
