The goal of the Push-Pull Sub-Saharan Africa Project (PPSSA) is to enhance the widespread application of Push-Pull technology (PPT), to reach many smallholder farmers through an integration of the technology in their farming systems. The project is funded by the Biovision Foundation for Ecological Development, Switzerland, for a period of two years, spanning from December 2016 to December 2018, with a target to reach 350,000 farmers in Sub-Saharan Africa; with 20% adoption (70,000 new farmers) by December 2018. Push-Pull expansion has been implemented in several countries with the Technology Transfer Unit (TTU) training farmers as a way of building local capacity for scaling out Push-Pull.
Push-Pull Technology involves intercropping maize with a repellent plant, such as Desmodium, and planting an attractant trap plant, such as Napier grass or Brachiaria, as a border crop around the intercrop. Gravid stemborer females are repelled or deterred away from the target crop (push) by stimuli that mask host apparency while they are simultaneously attracted (pull) to the trap crop, leaving the target crop protected. Desmodium produces root exudates some of which stimulate the germination of Striga seeds and others inhibit their growth after germination. This combination provides a novel means of in situ reductions of the Striga seed bank in the soil through efficient suicidal germination even in the presence of graminaceous host plants. Desmodium is a perennial cover crop (live mulch) which is able to exert its control effect on Striga even when the host crop is out of season, and together with Napier grass protect fragile soils from erosion. It also fixes nitrogen, conserves soil moisture, enhances arthropod abundance and diversity and improves soil organic matter, thereby enabling cereal cropping systems to be more resilient and adaptable to climate change, while providing essential environmental services, and making farming systems more robust and sustainable.
This conservation agricultural approach was developed by scientists at the International Centre of Insect Physiology and Ecology (icipe), in Kenya and Rothamsted Research, in the United Kingdom, in collaboration with other national partners for the integrated management of stemborers, Striga weed, soil fertility and now the Fall Armyworm.