Kohgiluyeh and Boyerahmad Agricultural and Natural Resources Research and Education Center, Dryland Agricultural Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Gachsaran, Iran.
Department of Plant Breeding and Biotechnology, Sari Agricultural Sciences and Natural Resources University, Sari, Iran.
BMC Plant Biol. 2024 Jul 19;24(1):687. doi: 10.1186/s12870-024-05397-7.
The effect of azelaic acid (Aza) on the response of tomato plants to Alternaria solani was investigated in this study. After being treated with Aza, tomato plants were infected with A. solani, and their antioxidant, biochemical, and molecular responses were analyzed.
The results demonstrated that HO and MDA accumulation increased in control plants after pathogen infection. Aza-treated plants exhibited a remarkable rise in peroxidase (POD) and catalase (CAT) activities during the initial stages of A. solani infection. Gene expression analysis revealed that both Aza treatment and pathogen infection altered the expression patterns of the SlNPR1, SlERF2, SlPR1, and SlPDF1.2 genes. The expression of SlPDF1.2, a marker gene for the jasmonic acid/ethylene (JA/ET) signaling pathway, showed a remarkable increase of 4.2-fold upon pathogen infection. In contrast, for the SlNPR1, a key gene in salicylic acid (SA) pathway, this increased expression was recorded with a delay at 96 hpi. Also, the phytohormone analysis showed significantly increased SA accumulation in plant tissues with disease development. It was also revealed that tissue accumulation of JA in Aza-treated plants was increased following pathogen infection, while it was not increased in plants without pathogen inoculation.
The results suggest that the resistance induced by Aza is mainly a result of modulations in both SA and JA pathways following complex antioxidant and molecular defense responses in tomato plants during A. solani infection. These findings provide novel information regarding inducing mechanisms of azelaic acid which would add to the current body of knowledge of SAR induction in plants as result of Aza application.
本研究探讨了壬二酸（Aza）对番茄植株应对交链格孢菌的影响。用 Aza 处理后，番茄植株被交链格孢菌感染，分析了它们的抗氧化、生化和分子反应。
结果表明，HO 和 MDA 在病原体感染后在对照植物中积累增加。在交链格孢菌感染的初期，Aza 处理的植物表现出过氧化物酶（POD）和过氧化氢酶（CAT）活性的显著升高。基因表达分析表明，Aza 处理和病原体感染都改变了 SlNPR1、SlERF2、SlPR1 和 SlPDF1.2 基因的表达模式。茉莉酸/乙烯（JA/ET）信号通路的标记基因 SlPDF1.2 的表达在病原体感染后显著增加了 4.2 倍。相比之下，水杨酸（SA）途径的关键基因 SlNPR1 的表达在 96 hpi 时延迟增加。此外，植物激素分析显示，随着疾病的发展，植物组织中 SA 的积累显著增加。研究还表明，在病原体感染后，Aza 处理的植物组织中 JA 的积累增加，而在没有病原体接种的植物中则没有增加。
结果表明，Aza 诱导的抗性主要是由于番茄在交链格孢菌感染过程中复杂的抗氧化和分子防御反应后 SA 和 JA 途径的调节。这些发现为壬二酸的诱导机制提供了新的信息，这将增加植物中由于 Aza 应用导致 SAR 诱导的现有知识体系。
