Ant abundance and Cosmopolites sordidus damage in plantain fields as affected by intercropping

- Intercropping altered ant community structure in a plantain agroecosystem.
- Plant damage by Cosmopolites sordidus was linked to ant abundance.
- Axinidris sp., Monomorium spp., Pheidole spp. and Tetramorium sp. decreased damage.

Intercropping is a practical way to increase plant diversity in agroecosystems and provide alternative food and habitat to arthropods, including generalist predators. In tropical agriculture, ants are important predators and have complex and often strong effects on pests. With the goal of optimizing control of the banana weevil, Cosmopolites sordidus, we studied maize (Zea mays), cocoyam (Xanthosoma sagittifolium), and bottle gourd (Lagenaria siceraria) as intercrops in a plantain field in Cameroon. We analyzed the effects of intercropping on ant abundance (by taxon) and on the damage caused by C. sordidus larvae to plantain corms. We also analyzed the relationship between ant abundance and C. sordidus damage. When added singly, the three intercropped plants significantly affected the abundance of each of the seven ant taxa but the sign of the effect depended on the intercropped plant species and on the ant taxon. Intercropping had clear effects on ant abundance, which was negatively correlated with C. sordidus damage for the Myrmicinae and positively correlated for the Formicinae and Ponerinae. Intercropping in plantain agroecosystems has the potential to alter ant community structure which contributes to C. sordidus control, but the effect of intercropped plant species remain unclear and further investigations are needed.