Optimising the multipurpose citron watermelon
The focus of Dr Richard Ngwepe’s doctoral research is a fruit that is close to his heart. He recalls how, while growing up in a village in Limpopo, South Africa, “my grandmother and mother used to prepare “Kgodu”, which is a porridge made from the ripened fruit flesh of citron watermelon.” The plant’s fresh leaves and seed were also eaten by the villagers, and it was fed to cattle, goats, and sheep.
He was fascinated by the ability of the crop to grow with minimal inputs, surviving extreme weather where other crops such as maize failed. Farmers grew many local varieties of the fruit, but there was little information documented about it.
Ngwepe’s interest in the citron watermelon continued while he pursued his studies, graduating with an MSc-Agric (Agronomy) in 2014 from the University of Limpopo.
Then he received an offer from Dr Jacob Mashilo to do a PhD in plant in breeding, focussing on citron watermelon. “I knew this was an opportunity to document useful information about the crop. I never hesitated,” he says. “Moreover, it was an opportunity to help conserve the tremendous genetic diversity of the crop for future generations and contribute to sustainable cultivation to enhance food and nutrition security.”
His PhD research entailed 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.
Ngwepe embarked on a mission to collect samples of the fruit grown by small-holder farmers in villages across Limpopo. Over 100 accessions were collected in the form of seeds and fruit samples and conserved at Towoomba Research Station, part of the Limpopo Department of Agriculture and Rural Development (LDARD).
“We extensively examined the phenotypic and genetic variation of the accessions,” he says. “Then followed the identification and selection of five unique parents for hybridization to develop ten experimental F1 hybrids. Thereafter, field evaluations were conducted for two years, and several high-yielding hybrids were identified. These are yet to be registered and commercialized for various uses in South Africa.”
Ngwepe is planning to do further research on citron watermelon. “I feel I we have not fully exploited all the research avenues related to the crop. I plan to write research proposals to acquire funding and offer possible supervision to future researchers interested in studying citron watermelon,” he says.
He thanks Professor Hussein Shimelis and Dr. Jacob Mashilo for their support, and the University of KwaZulu-Natal and the Limpopo Department of Agriculture and Rural Development for providing financial support.
Words: Shelagh McLoughlin
Photo: Supplied