Potential for Sweet Potato Improvement Through Breeding Identified in PhD Study

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Dr Nomusa Chizhande, a research officer at the Department of Research and Specialist Services in Zimbabwe, used her PhD research to identify genetic traits in sweet potato associated with high yield and improved nutritional quality, contributing to the development of high-yielding, nutrient-dense crop varieties with the potential to help combat malnutrition and improve farmer productivity.

Chizhande evaluated genetic variability in sweet potato germplasm to identify traits, including beta-carotene content, that make this a key food security crop, particularly in developing regions, highly valuable, and that could possibly be further developed to enhance its benefits and productivity for people who rely on it.

Chizhande’s undergraduate studies at the Zimbabwe Open University developed her strong foundation in crop science and genetics. She completed her master’s studies at Zimbabwe’s Africa University, focusing on maize hybrids with resistance to the Imazapyr herbicide, deepening her interest in plant improvement and research.

Passionate about improving crop productivity and resilience, especially in the face of climate change and food insecurity, Chizhande saw the potential of breeding to develop improved varieties that yield more while offering enhanced nutritional value to benefit communities and livelihoods.

Chizhande chose to pursue a PhD at the University of KwaZulu-Natal (UKZN) because of its strong reputation in agricultural sciences and its commitment to impactful research addressing food security challenges. She appreciated the University’s diverse academic environment, access to excellent research facilities, and the support from supervisors and peers that made her PhD journey enriching and rewarding.

Supervised by Professor Julia Sibiya, her thesis is titled: ‘Breeding Investigations for Fresh Root Yield and Nutritional Quality Traits for Sweetpotato (Ipomoea batatas [L.] Lam.) Germplasm’, she discovered significant genetic variation within the germplasm, highlighting the potential for substantial improvement through breeding. Some genotypes demonstrated both high yield and enhanced nutritional quality traits that are often challenging to combine, making them promising candidates for future cultivar development.

Chizhande’s research resulted in publications and conference presentations, which enriched her academic journey and professional growth.

She had to overcome challenges, including environmental variability and COVID-19 disruptions, to complete her research, doing so by staying adaptable, seeking guidance from her supervisor, and maintaining a disciplined approach. Support from colleagues and a positive mindset were also key.

The researcher juggled motherhood, part-time work and community involvement with her studies, sticking to a structured schedule, setting clear priorities, and ensuring she took time to rest and recharge to stay focused and productive.

She is committed to pursuing a career in plant breeding to contribute to crop improvement and food security initiatives. She is particularly interested in continuing research on sustainable agriculture and developing improved crop varieties that address both yield and nutritional challenges and is interested in pursuing academic advancement through a postdoctoral fellowship.

Chizhande thanked Sibiya for her guidance and mentorship, as well as her co-supervisors, and her family and friends for their unwavering support and encouragement.

Words: Christine Cuénod

Photograph: Supplied