Knowledge for a sustainable world

Food and Nutrition Security Initiative - FaNSI

NRI is pleased to announce the following PhD opportunities created under FaNSI:


Harnessing pollination services for increased bean yields in smallholder farming systems in East Africa (3E 2020 14)
Lead UK Supervisor: Professor Phil Stevenson
Partner/host Institution: Nelson Mandela African Institution of Science and Technology, Tanzania

Pollinators contribute to the yield of 75% of crops including most legumes. Pollination services (PS) benefit from florally rich natural and semi-natural habitat with abundant nectar and pollen while a lack of floral resources contributes to pollinator decline. However, plant species richness in and of itself may not always enhance PS. Interventions to supplement nectar and pollen provision and augment PS must be underpinned by evidence of the contribution of specific plants to key pollinators and their potential trade-offs as weeds. Not all flowers are important for all pollinators and not all flower visitors pollinate beans. This project will continue our work addressing knowledge gaps in PS in a bean agri-system in East Africa. 

We recently reported that field beans (Phaseolus vulgaris L.), from which pollinators were excluded, produced less than 50% of the yield than open pollinated or hand pollinated plants. Thus, where PS is sub-optimal, farmers could lose out on yield potential. To optimise PS in a bean agri-system the specific and most important pollinators need to be determined experimentally along with the margin plants that best support them. The overarching aim of this study is therefore to identify the key pollinators of beans and the margin flowers on which they forage through monitoring, observation and sequencing bee collected pollen.

The action will evaluate the impact of different crop fields, field margins and non-crop habitat on smallholder bean-maize farm ecosystem services at multiple scales and determine specifically the role of trees as components of bean system landscapes as pollinator forage and refuge. The candidate will also develop predictive tools to evaluate landscape traits for promoting pollination ecosystem services using spatial analysis. These objectives will be addressed through landscape and farm-scale assessments of floral resource and refuge for beneficial insects using high resolution spatial analysis, DNA sequencing, chemical analysis, and farm-scale assessment of pollination services as well as monitoring pollen deposition of specific pollinators and interactions between these pollinators and non-crop flowers.

The student will work primarily in Tanzania at the Sustainable Agriculture, Biodiversity and Ecosystem Management (SABEM) Department in Arusha at the Nelson Mandela African Institution of Science and Technology (for more information:  Molecular and chemical research will be undertaken in the UK at the Natural Resources Institute, University of Greenwich, UK.

Closing date for applications: 10/11/2020
Further details and how to apply:
 Link to Document

For further information, contact: Professor Phil Stevenson