Push-pull cropping system reduces pests and promotes the abundance and richness of natural enemies in brassica vegetable crops

Abstract

The push–pull cropping system can be a promising alternative for reducing pests by increasing and maintaining their natural enemies in different farming configurations. However, there is still a lack of information on its application, based on the diversification between plants in tropical conditions. In this experiment, we evaluated the effect of the push–pull system on the main pests and natural enemies in brassica crops. We evaluated two treatments: (a) kale as a monocrop; and (b) kale in a push–pull (marigold-mustard) system. In our study, the push–pull cropping system significantly suppressed the incidence of the main kale pests. In addition, the push–pull system offered higher abundance and richness of predator populations, as well as an increased rate of parasitism compared to the monocrop. These results suggest that the plants used to compose the diversification system are promising for composing the push–pull system in brassica crops. However, there is a need for further research to characterize the resources offered by these plants and their volatiles, as well as to understand how the landscape structure can affect the behavior of pests and natural enemies in the push–pull cropping system, especially in vegetable diversification in tropical agroecosystems.