Developing a ‘climate-smart’ tepary bean
Recurrent droughts and high temperatures due to climate change are adversely affecting legume cultivation in southern Africa. Dr Saul Eric Mwale’s research focused on developing a “new generation” of tepary bean cultivars that can withstand these weather conditions.
Mwale, a Malawian national, successfully completed an MSc in plant breeding and seed systems at Makerere University in Uganda in 2017, supported by an Intra-ACP scholarship from the EU. He then started his PhD study at the African Centre for Crop Improvement (ACCI), which was completed early this year.
Tepary bean, a drought-resilient legume crop from the arid regions of southwestern United States and northern Mexico, is cultivated in Africa by smallholder farmers. It is an exceptional source of protein and various nutrients, and has great potential to mitigate malnutrition in southern Africa.
Despite tepary bean’s nutritional value and resilience, it has been neglected by researchers and scientists in Africa, with no dedicated breeding program. Mwale has successfully bred tepary bean cultivars characterized by superior pod yields per plant, thus improving their productivity amidst recurrent droughts.
Mwale also undertook an evaluation of genetic variability in seed yield and yield-related traits among tepary bean genotypes under drought stress conditions. His study unveiled a wide range of genetic diversity in both seed yield and yield-related traits. Subsequently, promising parental lines were meticulously selected and used in the creation of a novel tepary bean breeding population, demonstrating considerable potential for subsequent advancement and eventual cultivar release.
Mwale’s research also identified unique quantitative trait nucleotides (QTNs) linked to 2,874 previously reported genes expressed in response to drought. These novel QTNs and putative candidate genes found in the study are important for trait introgression and marker-assisted selection in tepary bean and related legume crops.
He thanked Professor Hussein Shimelis for his support, as well as Dr. Jacob Mashilo, Dr. Abel Sefasi, Dr. Wilson Nkhata, and Dr. Isaac Fandika. He also thanked the National Research Fund and Kirk House Trust for financial support.
Mwale is currently lecturing in Genetics and molecular biology at Mzuzu University in Malawi.
Words: Shelagh McLoughlin
Photo: Supplied