Background

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Cowpea (Vigna unguiculata) is an important grain legume that contributes significantly to food security, nutrition, and household income among smallholder farmers in Botswana and across sub-Saharan Africa. Despite its tolerance to drought and poor soils, cowpea productivity remains low, largely due to infestation by the parasitic weed Alectra vogelii. This weed attaches to cowpea roots, causing severe nutrient depletion and substantial yield losses, particularly in low-input farming systems where effective control options are limited.

Host-plant resistance is the most sustainable and cost-effective strategy for managing Alectra vogelii. Although resistance genes such as Rav1, Rav2, and Rav3 have been identified in a limited number of cowpea accessions, the narrow genetic base of resistance poses a risk of resistance breakdown. There is a critical need to identify additional sources of resistance and to characterize their genetic basis. Screening diverse cowpea accessions will support the development of resilient cowpea varieties and enhance breeding efforts aimed at improving productivity and food security in Botswana and the region.

 

The primary focus of this study is to evaluate three hundred and one (301) cowpea accessions for Alectra vogelii resistance through comprehensive screening under controlled greenhouse conditions.