Push-Pull Biotechnology

We’re leading implementation of pioneering biological pest and weed control for one of Africa’s staple food crops.

The threat to Africa’s maize

Maize is the most widely grown crop in sub-Saharan Africa, and a staple crop for half our continent’s population. But like many cereal crops in Africa it’s affected by the parasitic weed Striga weed (or witchweed) which can grow more than a foot tall and reduce yields by one-third to 100%

Maize is also more vulnerable than sorghum and pearl millet to attack by stemborer moths, which can also cause 100% destruction of a maize crop, resulting in widespread hunger and poverty.

What is push-pull?

Push-pull is an innovative pest management technique developed by Kenya-based insect science research leaders the International Centre of Insect Physiology (ICIPE). It has proved to be highly effective in controlling both stemborer moths and Striga weed in a way that is environmentally friendly and cost-effective.

How does push-pull work?

The technique is straightforward. Farmers intercrop their maize with the legume crop Desmodium (also known as tick clover) which continuously produces defence odours that repel (push) stemborer moths away from the maize. Desmodium also deters the growth of the Striga weed.

The pull element is provided by Bracharia or Napier grass planted as a border crop around a maize plot. It offers the multiple benefits of being attractive to stemborers while also fixing nitrogen into soil, and being a nutritious animal feed.

The effectiveness of push-pull

• Provides animal feed for livestock or to sell at market
• Low-cost
• Nature-based: no herbicides or pesticides
• Enriches soil