Chemical insecticide application has been the most widely used form of insect pest management in last six decades and resulted in well-documented negative impacts. Habitat manipulation based on intercropping to exert direct effects on pests and promote biological control has been explored in various systems as a more sustainable option. A range of intercrop plants have been evaluated, with many studies reporting successes in terms of enhanced natural enemy density, reduced pest numbers and, less commonly, reduced crop loss. Economic benefit and cost-effectiveness are less frequently explored, despite the importance of these criteria in farmer adoption and scope to scale. Here we quantify the effects of contrasting experimental habitat management treatments on densities of the pest, cabbage webworm, Hellula undalis Fab. (Lepidoptera: Crambidae), crop yield and quality, profitability and cost: benefit ratio in a cabbage Brassica oleracea var. capitata (Brassicaceae) production system in West Africa. Six wild plant species were evaluated as intercrops to promote pest suppression. Ageratum conyzoides, Tridax procumbens (Asteraceae), Crotalaria juncea (Fabaceae), Cymbopogon citratus (Poaceae), Lantana camara (Verbenaceae) and Talinum triangulare (Talinaceae) intercrop plantings were compared with a no-plant control treatment in a randomised block experiment over three growing seasons in Ghana. Costs of gathering plant propagules and establishing each intercrop plant were recorded, as was the market value of cabbage from each treatment, allowing the calculation of precise cost: benefit ratios. Hellula undalis larvae were numerous in the control compared with the intercrop plant treatments. The intercrop treatments had higher undamaged yields compared with the control. Reflecting this, and establishment costs, intercrop plant treatments had better cost: benefit ratios than the control, ranging from 1:2.8 for C. citratus to 1:46.6 for A. conyzoides. These findings provide an important evidence base for considering the economic case for habitat manipulation control and highlight that the identity of plants used in this type of agricultural intervention has a major effect on the economic outcome.

过去六十年来，化学杀虫剂的使用一直是最广泛使用的害虫管理形式，并导致了有据可查的负面影响。基于间作对害虫产生直接影响并促进生物控制的栖息地操纵已在各种系统中作为更可持续的选择进行了探索。对一系列间作植物进行了评估，许多研究报告称，在提高天敌密度、减少害虫数量以及减少作物损失方面取得了成功。尽管这些标准在农民采用和规模扩大方面很重要，但对经济效益和成本效益的探讨较少。在这里，我们量化了对比实验栖息地管理处理对害虫、卷心菜网虫、Hellula undalis密度的影响很好。（鳞翅目：蟹科）、作物产量和质量、盈利能力和成本：甘蓝甘蓝变种的效益比。西非的capitata（十字花科）生产系统。六个野生植物物种被评估为间作以促进害虫抑制。Ageratum conyzoides , Tridax procumbens (Asteraceae), Crotalaria juncea (Fabaceae), Cymbopogon citratus (Poaceae), Lantana camara (Verbenaceae) 和Talinum trianglee（Talinaceae）间作种植与无植物对照处理在加纳的三个生长季节的随机区组试验中进行了比较。记录了收集植物繁殖体和建立每个间作植物的成本，以及每个处理的卷心菜的市场价值，从而可以计算出精确的成本：收益比。与间作植物处理相比，对照中的海葵幼虫数量众多。与对照相比，间作处理具有更高的未损伤产量。反映这一点，并建立成本，间作植物疗法有更好的成本：效益比率比对照，从1：2.8 C. citratus为1：46.6的胜红蓟. 这些发现为考虑栖息地操纵控制的经济案例提供了重要的证据基础，并强调了在此类农业干预中使用的植物特性对经济结果有重大影响。