Research Institute of Organic Agriculture FiBL, Frick, Switzerland.
Natural Products Research Group, Department of Chemistry, University of Surrey, UK.
Pest Manag Sci. 2018 Feb;74(2):477-488. doi: 10.1002/ps.4733. Epub 2017 Nov 21.
Plant extracts might provide sustainable alternatives to copper fungicides, which are still widely used despite their unfavourable ecotoxicological profile. Larch bark extract and its constituents, larixyl acetate and larixol, have been shown to be effective against grapevine downy mildew (Plasmopara viticola) under semi-controlled conditions. The aim of this study was to reduce the gap between innovation and the registration of a marketable product, namely to develop scalable extraction processes and to evaluate and optimise the performance of larch extracts under different conditions.
Toxicologically and technically acceptable solvents like ethanol were used to extract the active compounds larixyl acetate and larixol from bark in sufficient amounts and their combined concentration could be increased by up to 39% by purification steps. The combined concentration of larixyl acetate and larixol from larch turpentine could be increased by up to 66%. The Minimal Inhibitory Concentration (MIC ) against P. viticola in vitro (6-23 µg mL ) and the Effective Concentration (EC ) in planta under semi-controlled conditions (0.2-0.4 mg mL ) were promising compared with other plant extracts. In vineyards, efficacies of larch extracts reached up to 68% in a stand-alone strategy and 84% in low-copper strategies.
Larch extracts represent valid candidates for copper reduction in organic vineyards, and their development into a sustainable plant protection product might be feasible. © 2017 Society of Chemical Industry.
植物提取物可能为铜杀菌剂提供可持续的替代品，尽管铜杀菌剂具有不良的生态毒理学特性，但它们仍被广泛使用。在半控制条件下，落叶松树皮提取物及其成分乙酸紫丁香酯和落叶松醇已被证明对葡萄霜霉病（Plasmopara viticola）有效。本研究的目的是缩小创新与有销售潜力产品注册之间的差距，即开发可扩展的提取工艺，并在不同条件下评估和优化落叶松提取物的性能。
采用乙醇等在毒理学和技术上可接受的溶剂，从树皮中提取有效化合物乙酸紫丁香酯和落叶松醇，并通过纯化步骤将其浓度提高 39%。从落叶松松节油中提取的乙酸紫丁香酯和落叶松醇的总浓度可提高 66%。与其他植物提取物相比，落叶松提取物对 P. viticola 的体外最小抑菌浓度（MIC）（6-23 µg mL）和半控制条件下的有效浓度（EC）（0.2-0.4 mg mL）有很大的希望。在葡萄园，落叶松提取物在独立策略中的效率高达 68%，在低铜策略中的效率高达 84%。
落叶松提取物是有机葡萄园减少铜用量的有效候选物，将其开发成可持续的植保产品可能是可行的。© 2017 化学工业协会。
