Kaolin Particle Film Protects Grapevine cv. Cabernet Sauvignon Against Downy Mildew by Forming Particle Film at the Leaf Surface, Directly Acting on Sporangia and Inducing the Defense of the Plant

• DOI: 10.3389/fpls.2021.796545
• Publication Date: 2022-01-10T05:58:25Z
• Authors: Ying Wang; Xiao Cao; Yulei Han; Xing Han; Zhilei Wang; Tingting Xue; Qiuhong Ye; Liang Zhang; Xinyao Duan; Hua Wang; Hua Li
• Keywords: Plasmopara viticola; Jasmonic acid; Callose

Downy mildew is a major threat to viticulture, leading severe yield loss. The use of traditional copper-based fungicides effective, but has adverse effects on the environment and human health, making it urgent develop an environmentally friendly disease management program. Multi-functional kaolin particle film (KPF) promising as effective safer treatment strategy, since this material lacks chemically active ingredients. In study, ability Kaolin pretreatment protect grapevine leaves from Plasmopara viticola was tested mode action KPF analyzed. application reduced severity development intercellular hyphae. Additionally, there accumulation H2O2 malondialdehyde (MDA) with pretreatment. observation ultrastructure leaf surface showed deposition stomatal obstruction, indicating that protected plants against by preventing adhesion pathogens blocking invasion through stomata. also activated host defense responses, evidenced increased activities anti-oxidative enzymes [superoxide dismutase (SOD), peroxidase (POD), catalase (CAT)] defense-related [phenylalanine ammonia-lyase (PAL), chitinases, β-1,3-glucanases], phytohormone signals [abscisic acid (ABA), salicylic (SA), jasmonic (JA)] up-regulation genes related plant defense. Overall, these results demonstrate counters downy protecting enhancing responses.