Fungal endophytes for the management of the bean stem maggot

The common bean, Phaseolus vulgaris L., is important in Africa, as it serves as a source of calories, protein, oil and micronutrients, for households that cannot afford meat.

However, its production is affected by the bean stem maggot (BSM), Ophiomyia spp. Farmers use chemical control and traditional approaches to control the pest; however, these strategies are inefficient, due to the complex behaviour of BSM.

In a recent study, icipe builds on its extensive research on the use of entomopathogenic fungi (EPF) to manage crop insect pests, to explore the potential of fungal endophytes to control BSM. The researchers found most fungal isolates from icipe germplasm capable of colonising different bean plant parts (root, stem, and leaves). They observed that the application of the fungal isolates on bean plants reduced the ability of the pest to feed and lay eggs, which in turn affected the emergence of pupae and development into adults.

A fungal isolate known as ICIPE 20, developed by the Centre from Metarhizium anisopliae, a fungus that grows naturally in the soil, was most effective in interfering with BSM life cycle. Another isolate of M. anisopliae, ICIPE 78, also led to a significant reduction in the number of BSM pupae and adults. The study demonstrates that fungal endophytes can be considered as tools for the management of BSM in East Africa.

Fungal endophytes

The research was funded by the Centre’s Innovative Seed Research Grants, which are funded through icipe core funding, provided by: Aid for Africa, USA; Federal Ministry for Economic Cooperation and Development (BMZ), Germany; Ministry of Higher Education, Science and Technology, Kenya; Swiss Agency for Development and Cooperation (SDC), Switzerland; Swedish International Development Cooperation Agency (Sida) and UK Aid, Government of the United Kingdom. Publication link: http://link.springer.com/article/10.1007/s10340-015-0725-4