State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China; Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture and Rural Affairs, Yangling, 712100, Shaanxi, China.
State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China; Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture and Rural Affairs, Yangling, 712100, Shaanxi, China.
Plant Physiol Biochem. 2019 Nov;144:244-253. doi: 10.1016/j.plaphy.2019.09.049. Epub 2019 Sep 30.
The wild Chinese grapevines (Vitis spp.) show varying levels of resistance to powdery mildew caused by Erysiphe necator that is an economically important disease of cultivated grapevines (Vitis vinifera). However, little information is available regarding the cytological mechanisms of powdery mildew resistance in these wild relatives. Here, we studied the cytological responses of three wild Chinese grapevine accessions after they were infected with E. necator (En) NAFU1 in comparison to the susceptible V. vinifera cv. 'Thompson Seedless' grape. The hyphal growth and sporulation of En NAFU1 were significantly restricted in wild species compared to 'Thompson Seedless', which appears to be associated with early cell wall deposition at the attempt sites, encasement of haustoria, and hypersensitive response-like cell death of penetrated epidermal cells. Moreover, endogenous free salicylic acid (SA) was more abundant in wild Chinese Vitis species than in 'Thompson Seedless' under pathogen-free condition. During En NAFU1 colonization, SA conjugates accumulated higher in wild grapevines than in 'Thompson Seedless'. In addition, the species-specific expression patterns of defense-associated genes during En NAFU1 colonization indicated that mechanisms underlying powdery mildew resistance are divergent among different wild Chinese Vitis species. These results contribute to understanding of mechanisms underlying defense responses of wild Chinese Vitis species against powdery mildew.
中国野生葡萄(Vitis spp.)对由白粉菌(Erysiphe necator)引起的白粉病表现出不同程度的抗性，白粉病是栽培葡萄(Vitis vinifera)的一种重要经济病害。然而，关于这些野生近缘种对白粉病抗性的细胞学机制的信息很少。在这里，我们研究了三种中国野生葡萄品种在感染白粉菌(En)NAFU1 后的细胞学反应，与易感品种‘Thompson Seedless’葡萄进行了比较。与‘Thompson Seedless’相比，En NAFU1 在野生种中的菌丝生长和孢子形成受到明显限制，这似乎与在尝试部位早期沉积细胞壁、包裹吸器和穿透表皮细胞的过敏反应样细胞死亡有关。此外，在无菌条件下，中国野生葡萄物种中的内源游离水杨酸(SA)比‘Thompson Seedless’中更丰富。在 En NAFU1 定殖过程中，野生葡萄中的 SA 缀合物积累量高于‘Thompson Seedless’。此外，在 En NAFU1 定殖过程中防御相关基因的种特异性表达模式表明，不同中国野生葡萄种对白粉病抗性的机制是不同的。这些结果有助于理解中国野生葡萄种对白粉病防御反应的机制。
