Ecological Chemistry of Pest Control in Push-Pull Intercropping Systems: What We Know, and Where to Go?






Chemical ecology, Desmodium spp. (tick clover), Pest management, Sustainable agricultural intensification, Zea mays (maize)


Push-pull technology (PPT) employs mixed cropping for sustainable intensification: an intercrop repels or suppresses pests of the focal crop (push), while a trap crop attracts pests out of the field (pull), where they may be targeted for control. Underlying chemical-ecological mechanisms have been demonstrated in controlled settings, primarily for some of the best-established cereal PPT systems developed in east Africa. Yet, many questions remain regarding mechanisms, and strategies to adapt PPT for different crops and locations. We conducted a systematic review of scientific literature on PPT and related practices for biological control of pests of food and fodder. Of 3335 results, we identified 45 reporting on chemistry of trap- or intercropping systems for pest control, of which 30 focused on cereals or African pests. Seven of these reported primary chemical data: measurements from glasshouse and laboratory studies (5), or of field-collected samples (2). From these 30, we provide a database of compounds, discussing degrees of evidence for their mediation of push-pull. We depict hypothesized spatial distributions of selected compounds in PPT fields from physical properties and emission/exudation rates, and design of the east African cereal PPT system, and discuss influences on activity in field settings likely to affect success.

Funding data




How to Cite

J. Lang, F. Chidawanyika, Z. R. Khan, M. C. Schuman, Chimia 2022, 76, 906, DOI: 10.2533/chimia.2022.906.



Scientific Articles