Faculty of Engineering Sciences and Mathematics, Fermentation and Formulation of Biologicals and Chemicals, University of Applied Sciences Bielefeld, Bielefeld, Germany.
Department for Crop Sciences, Agricultural Entomology, University of Göttingen, Göttingen, Germany.
Pest Manag Sci. 2018 Jul;74(7):1575-1585. doi: 10.1002/ps.4842. Epub 2018 Mar 2.
Wireworms (Coleoptera: Elateridae) are major insect pests of worldwide relevance. Owing to the progressive phasing-out of chemical insecticides, there is great demand for innovative control options. This study reports on the development of an attract-and-kill co-formulation based on Ca-alginate beads, which release CO and contain neem extract as a bioinsecticidal compound. The objectives of this study were to discover: (1) whether neem extract can be immobilized efficiently, (2) whether CO -releasing Saccharomyces cerevisiae and neem extract are suitable for co-encapsulation, and (3) whether co-encapsulated neem extract affects the attractiveness of CO -releasing beads towards wireworms.
Neem extract was co-encapsulated together with S. cerevisiae, starch and amyloglucosidase with a high encapsulation efficiency of 98.6% (based on measurement of azadirachtin A as the main active ingredient). Even at enhanced concentrations, neem extract allowed growth of S. cerevisiae, and beads containing neem extract exhibited CO -emission comparable with beads without neem extract. When applied to the soil, the beads established a CO gradient of >15 cm. The co-formulation containing neem extract showed no repellent effects and was attractive for wireworms within the first 24 h after exposure.
Co-encapsulation of S. cerevisiae and neem extract is a promising approach for the development of attract-and-kill formulations for the control of wireworms. This study offers new options for the application of neem extracts in soil. © 2017 Society of Chemical Industry.
钢丝（鞘翅目：Elateridae）是具有全球重要性的主要昆虫害虫。由于化学杀虫剂的逐步淘汰，人们对创新的控制选择有很大的需求。本研究报告了一种基于海藻酸钠珠的诱捕和杀死共配方的开发，该配方释放 CO 并含有印楝提取物作为生物杀虫化合物。本研究的目的是发现：（1）印楝提取物是否可以有效地固定化，（2）释放 CO 的酿酒酵母和印楝提取物是否适合共包封，以及（3）共包封的印楝提取物是否会影响释放 CO 的珠粒对钢丝的吸引力。
印楝提取物与酿酒酵母、淀粉和糖化酶共包封，包封效率高达 98.6%（基于作为主要活性成分的印楝素 A 的测定）。即使在增强的浓度下，印楝提取物也允许酿酒酵母生长，并且含有印楝提取物的珠粒表现出与不含印楝提取物的珠粒相当的 CO 释放。当应用于土壤时，珠粒建立了 >15 cm 的 CO 梯度。含有印楝提取物的共配方没有表现出驱避作用，并且在暴露后的前 24 小时内对钢丝具有吸引力。
酿酒酵母和印楝提取物的共包封是开发用于控制钢丝的诱捕和杀死配方的有前途的方法。本研究为在土壤中应用印楝提取物提供了新的选择。 © 2017 化学工业协会。
