کاربرد رایزوباکتری‎های محرک رشد (PGPRs) در القای پاسخ‎های دفاعی آنزیمی و غیرآنزیمی پیچ تلگرافی در برابر ویروس موزاییک پیچ تلگرافی

Vinca minor or lesser periwinkle is a perennial, herbaceous, and creeping plant belonging to the Vinca genus and Apocynaceae family. In addition to being an ornamental and cover plant, V. minor is a valuable plant in folk and modern medicine. So far, more than 150 alkaloids have been isolated from the aerial parts and roots of this plant. Some of these alkaloids, including vinblastine, vincristine, and catharanthine, are anticancer agents. Also, V. minor contains monomeric eburnamine-type indole alkaloids such as vincamines, which have modulatory effects on brain circulation, neuronal homeostasis, and neuroprotective potencies. Vinca mosaic virus belongs to the potyvirus genus (Potyviridae), which has already identified by Next Generation Sequencing (NGS). VMV causes severe to mild mosaic, yellowing, blistering, and leaf curl symptoms in the lesser periwinkle leaves. So far, various strategies have been developed to control viral diseases, including the chemical control of vectors, sanitation, and breeding of virus-resistant/tolerant cultivars through conventional breeding techniques. However, public concerns about emerging pesticide-resistant phytopathogens and environmental contaminants have limited their applications. Also, the time-consuming crossing process, limited availability of natural resistance sources at the commercial level, and environmental safety issues on genetically modified crops have limited success in these techniques. Therefore, exploration of the environmentally friendly agents for plant viral disease management seems necessary. We evaluated the potential use of PGPRs elicitor against VMV infection to stimulate resistance induction and enzymatic and non-enzymatic defense in the lesser periwinkle plants against VMV. Our findings showed the application of Bacillus subtilis and Bacillus pumilus causes a significant increase in the phenol content, ROS-scavenging enzymes, and photosynthetic pigments content in the viral infected lesser periwinkle plants compared to the control plants. Therefore, the use of Bacillus spp. as a biotic elicitor causes an increase in lesser periwinkle resistance. To our knowledge, this is the first report that investigates the effect of elicitors on increasing phenolic compounds, photosynthetic pigments, and ROS-scavenging enzymes content in V. minor.