樟树枝叶提取物防治葡萄霜霉病的效果

为明确樟树枝叶提取物对葡萄霜霉病的防治效果,采用混合液滴显微镜观察法研究了樟树枝叶提取物及其活性成分对病原菌孢子囊萌发的抑制作用,利用高效液相色谱法鉴定了枝叶乙酸乙酯萃取物的化学成分,测定了其活性成分对葡萄霜霉病的室内和田间防治效果。结果表明,浓度为0.1 g/mL以上的樟树枝叶提取物对孢子囊萌发均有很好的抑制效果,抑制率达100.0%;樟树枝叶提取物经不同极性有机溶剂萃取后,分别获得正己烷、乙酸乙酯、正丁醇和水相分离物,浓度为1.0%时各分离物对孢子囊萌发的抑制率分别为58.4%、92.4%、32.5%和58.7%,乙酸乙酯相富集了主要抑菌活性成分,经液相色谱分析并与色谱库数据比对,确定其活性成分中含有芦丁和槲皮素;浓度为1.0%的芦丁和槲皮素对孢子囊具有抑制作用;田间试验显示,浓度为0.3 g/mL以上的枝叶提取物对葡萄霜霉病预防效果显著,治疗效果在60.0%以上。研究表明,樟树枝叶提取物可以有效控制葡萄霜霉病,提取物的活性成分芦丁和槲皮素可以作为植物源药剂。

Control of grape downy mildew with the extracts of branches and leaves of camphor tree Cinnamomum camphora

To investigate the control efficacy of camphor tree Cinnamomum camphora extracts against grape downy mildew, the inhibitory effects of C. camphora extracts and its effective components on sporangial germination of Plasmopara viticola in mixed drops on glass slides were determined through the observation of germinated sporangia under microscope. Efficient inhibitory compounds in the phase of ethyl acetate extract were identified with high performance liquid chromatography, and the control effects of main active components against grape downy mildew were tested both in laboratory and vineyards. The results showed that the extracts had the inhibitory effect on sporangial germination at 0.1 g/mL or higher concentrations, and the inhibition rate reached 100.0%. The extracts were obtained via the isolates from out of phase of n-hexane, ethyl acetate, n-butanol and water by organic solvents of different polarities, and the inhibition rates of sporangial germination were 58.4%, 92.4%, 32.5% and 58.7% at the concentration of 1.0%, respectively. The most effective compounds were distributed in the phase of ethyl acetate, and there were bothrutin and quercetin. The rutin and quercetin had strong inhibition activity on sporangial germination at the concentration of 1.0%. In field experiment, the extracts of camphor tree at 0.3 g/mL or higher showed significantly preventive effect, and the control rates with P.viticola were over 60.0%. The results indicated the main active components, rutin and quercetin of camphor tree extracts could effectively control and be developed as biocontrol fungicides for grape downy mildew.