葡萄叶提取物对葡萄霜霉病的防治作用及有效成分分析

为探究葡萄叶提取物对葡萄霜霉病的防治作用,测定了葡萄叶提取物及其有效物质对葡萄生单轴霉Plasmopara viticola孢子囊和游动孢子的抑制作用以及对葡萄霜霉病的防治效果,观察了其对葡萄生单轴霉在叶片中扩展、产生孢子囊能力的影响,并对葡萄叶提取物组成成分进行了分析。结果表明,葡萄叶提取物对葡萄生单轴霉孢子囊的形成和萌发均有明显的抑制作用。当葡萄叶提取物浓度为10 mg/mL时,其对孢子囊形成的抑制率为82.4%,葡萄生单轴霉孢子囊和游动孢子的萌发率仅为7.6%和1.1%,均显著低于无菌水处理。荧光显微观察发现,葡萄叶提取物可以抑制葡萄生单轴霉在叶片内的扩展。当葡萄叶提取物浓度为10 mg/mL和50 mg/mL时,对葡萄霜霉病的室内防治效果分别为80.1%和100.0%;且浓度为10 mg/mL的葡萄叶提取物对葡萄霜霉病的田间预防效果为67.8%,与烯酰吗啉处理无显著差异。液质联用技术检测显示,葡萄叶提取物中含有白藜芦醇和紫檀芪,其对葡萄生单轴霉均有显著的抑制作用,且紫檀芪的抑制效果强于白藜芦醇。

Control of grape downy mildew with extracts of grape leaves and analysis of its effective components

In order to explore the control effects of grape leaf extract (GLE) on grape downy mildew, the inhibitory effects of GLE and its effective components on sporangia and zoospores of Plasmopara viticola, and the control of grape downy mildew were determined, the spreading process of P. viticola in tissue of grape leaves and sporangial production were observed, and main active components of GLE were analyzed as well. The results showed that GLE had a strong inhibition effect on production and germination of sporangia of P. viticola. GLE significantly reduced sporangial production of P. viticola, with inhibition rate of 82.4% at 10 mg/mL, and germination rates of sporangia and zoospores were 7.6% and 1.1% at 10 mg/mL, both significantly lower than that of sterilized water. GLE could suppress the hyphae of P. viticola growth in the tissue of grapevine leaves based on observations under epi-fluoresence microscope. The control effect of GLE at 10 mg/mL and 50 mg/mL on grape downy mildew in vitro was 80.1% and 100.0%, respectively. The field preventive efficiency of GLE on grape downy mildew was 67.8% at 10 mg/mL, with no significant difference from that of dimethomorph. The active components of GLE contained resveratrol and pterostilbene by high performance liquid chromatography-mass spectrometry analysis, and they both had significant inhibition effects on P. viticola, but the inhibitive ability of pterostilbene was stronger than that of resveratrol.