School of Agricultural, Earth and Environmental Sciences

UKZN’s ACCI plant breeding PhD graduates, from left: Dr Armel Rouamba; Dr Nomathemba Majola; supervisor, Professor Hussein Shimelis; Dr Saul Eric Mwale; Dr Richard Ngwepe; and right, Dr Silindile Mkhabela.

PhD Graduates Boost Africa’s Plant Breeding Expertise

UKZN’s African Centre for Crop Improvement (ACCI) is celebrating the accomplishments of five PhD graduates representing three African countries and five different crops who have investigated how to enhance the traits of their chosen crops to resist disease, tolerate drought, respond to biocontrol agents, and provide better yield and nutritional quality.

Dr Nomathemba Majola, a lecturer in quantitative genetics at the University of Pretoria, took on breeding Bambara groundnuts for enhanced yield and nutritional quality. Supervised by UKZN’s Professor Hussein Shimelis, the Director of the ACCI, and Dr Abe Gerrano of the Agricultural Research Council (ARC), Majola documented the progress made on Bambara groundnut production, utilisation and genetic improvement in sub-Saharan Africa (SSA) to discern the critical production constraints, genetic resources and analysis, breeding methods and gains on yield and nutrition to guide breeding.

This indigenous crop species is neglected by researchers and underutilised in value chains but has the potential to help solve South Africa’s micronutrient deficiency problems by being a part of a more diverse food system and an alternative source of plant-based minerals and proteins, as well as a cash crop. Majola’s study resulted in two publications in high-impact journals.

Dr Silindile Mkhabela, whose PhD journey began just after the birth of her first child, is a lecturer at the University of Limpopo, where she completed her undergraduate studies. Also supervised by Shimelis and Gerrano, she focused on the pre-breeding of okra as an underutilised crop under drought stress conditions. She evaluated it based on morphological, physiological traits and molecular markers at UKZN’s Ukulinga Research Farm and Controlled Environment Facility (CEF), crossing superior, drought-tolerant genotypes at the ARC in Pretoria, with further evaluation taking place in the field in the North West and Limpopo provinces to provide recommendations for further breeding.

Okra has essential nutrients that could reduce malnutrition among low-income populations in Asia and sub-Saharan Africa, where it is cultivated. The limited research on this crop in South Africa made it an interesting subject of study.

Dr Saul Mwale is from Malawi where he works as a lecturer at Mzuzu University. His research, supported by funding from South Africa’s National Research Foundation and the Kirkhouse Trust in the United Kingdom and supervised by Shimelis, contributed to developing a new generation of tepary bean cultivars that exhibit superior pod yields per plant, making them more productive despite recurrent droughts and mitigating vulnerabilities to micronutrient and macronutrient deficiencies prevalent among children and women in southern Africa.

Mwale’s study evaluated the genetic variability in seed yield and yield-related traits among tepary bean genotypes under drought stress conditions, revealing a wide range of genetic diversity in both seed yield and yield-related traits. He selected promising parental lines to create a novel tepary bean breeding population with the potential for subsequent advancement and eventual cultivar release and identified unique quantitative trait nucleotides that are important for trait introgression and marker-assisted selection in tepary bean and related legume crops. Mwale’s research was published in three journals.

Dr Richard Ngwepe of Limpopo province where he works at the Limpopo Department of Agriculture and Rural Development (LDARD), conducted his research on a pre-breeding and breeding programme to identify and select unique and complementary genotypes for production, value-adding, and potential commercialisation of citron watermelon in South Africa. Inspired by the Kgodu porridge his mother and grandmother used to make derived from the ripened fruit flesh of citron watermelon as well as other traditional foods, Ngwepe was fascinated by the crop’s use for human and animal food, and the crop’s ability to grow in marginal areas with very few production inputs.

Through his study, Ngwepe hoped to contribute to conserving the genetic diversity of the crop for future generations and contributing to sustainable cultivation to enhance food and nutrition security. Supervised by Shimelis and Dr Jacob Mashilo of LDARD, he worked with smallholder farmers in different villages across the Limpopo province to collect seed and fruit samples, extensively examining the phenotypic and genetic variation of the accessions and identifying and selecting five unique parents for hybridisation, followed by field evaluations to identify high-yielding hybrids that could be registered and commercialised for various uses in South Africa.

Dr Armel Rouamba of Burkina Faso conducted his study on a staple crop in his country: pearl millet. The crop grows in areas with poor soil conditions, erratic rainfall and high temperatures, and its productivity is primarily constrained by the parasitic weed Striga hermonthica. Rouamba hoped to develop Striga-resistant pearl millet varieties adapted to semi-arid regions with the desirable farmer and market-preferred traits to enhance yield gains and sustainable production.

His objective was to improve pearl millet production and productivity in Burkina Faso by developing pearl millet varieties with Striga-resistance and compatibility with a biocontrol agent, Fusarium oxysporum, and adapted to local agroecologies. His study highlighted significant genetic diversity among genotypes for Striga resistance and identified the best-performing genotypes selected as suitable parents for breeding for Striga resistance, recommending them for production and as donor parents for further improvement breeding. Rouamba achieved six publications in high-impact journals.

Despite the loss of both his parents during his research, Rouamba’s study was also punctuated with joy in the births of his two daughters. His research was supervised by Shimelis and supported by the International Crops Research Institute for the Semi-Arid Tropics through its Harnessing Opportunities for Productivity Enhancement for Sorghum and Millets and Accelerated Varietal Improvement and Seed Systems in Africa projects, funded by the Bill & Melinda Gates Foundation.

Rouamba continues to work on improving pearl millet varieties to enhance yield through open-pollinated and hybrid Striga-resistant varieties featuring farmers’ preferred traits in Burkina Faso.

The African Centre for Crop Improvement was established in 2002 and has enabled the education of a new generation of African plant breeders working on the crops important to African agriculture, in Africa.

‘These ACCI alumni constitute a new generation of plant breeders who are now leading the crop breeding programmes of national agricultural research systems (NARS), universities, the private sector and international research centres in some 20 countries in Africa,’ said Shimelis.

‘These ACCI-trained breeders currently constitute a significant proportion of all active plant breeders in these countries. The ACCI-educated plant breeders have released over 200 new crop varieties in a wide range of crops that are vital for food security throughout eastern, southern and West Africa.’

The ACCI has successfully graduated 155 African plant breeders to date.

Words: Christine Cuenod

Photographs: Sethu Dlamini