Push-Pull: Chemical Ecology-Based Integrated Pest Management Technology.

Area of Science:

• Agricultural Science
• Ecology
• Agronomy

Background:

• Cereal crops in sub-Saharan Africa face significant yield losses from lepidopterous stemborers and parasitic Striga weeds.
• Smallholder farmers often lack resources for expensive chemical pest and weed control methods.

Purpose of the Study:

• To introduce and evaluate the push-pull technology as an integrated pest and weed management strategy for cereal-livestock farming systems in Africa.
• To highlight the chemical ecology-based approach utilizing semiochemicals for pest and weed control.

Main Methods:

• Implementation of push-pull technology involving trap crops (pull) to attract stemborers and repellent intercrops (push) to deter them from the main cereal crop.
• Utilizing allelopathic mechanisms of leguminous intercrops, specifically flavonoid compounds in root exudates, to control Striga weed germination and attachment.
• Incorporating nitrogen-fixing and soil-improving intercrops to enhance soil fertility and provide animal fodder.

Main Results:

• The technology effectively manages stemborer pests and Striga weeds, leading to significant increases in maize yields.
• Root exudates of intercrops induce suicidal germination and inhibit attachment of Striga hermonthica seeds.
• Intercropping enhances soil fertility, provides valuable animal fodder, and diversifies farmer income.

Conclusions:

• Push-pull technology is an economical and effective sustainable agricultural practice for smallholder farmers in Africa.
• The integrated approach addresses major crop production constraints, improves livelihoods, and is based on locally available resources.
• Widespread adoption by over 125,000 farmers in eastern Africa demonstrates its practical success and scalability.