Professor Steven Runo, a molecular biologist at Kenyatta University, Kenya, was recently announced winner of Royal Society Africa Prize for best scientific research in Africa 2020. This award was given in the backdrop of his extensive research over past decade on Striga (witchweed), a parasitic plant devastating cereal production in Sub-Saharan Africa.

Striga is not a well-known parasitic plant to many people but professor likens it to a pandemic with ability to destroy a crop with up to 65-100% yield loss. The parasitic weed affects key regional staple cereal crops maize, sorghum, millet, and rice. It is a threat to food security as it is easily disregarded and yet very difficult to control. Striga produces numerous tiny seeds that are easily dispersed and can hibernate in the soil at a dormant stage for up to 20 years! They would only germinate after a host is located when they detect germination stimulants. Striga, a purple-pink coloured weed, is ideally referred to as ‘witchweed’ and Runo whose twitter handle best describes him is ‘on the heels of a cereal killer!’

The head of Biochemistry, Microbiology and Biotechnology Department employs molecular biology tools and genomics to understand the nature of Striga in sorghum and has developed interventions that can safeguard against enormous economic losses in crop production. The wining research was on elucidating pathways for long distance RNA trafficking between parasitic plants and their hosts. In a recent interview, he observed that “witchweed literally sucks the life out of its host by siphoning out water and nutrients. What remains is a stunted, discoloured host and inevitable death of the entire crop”. He envisions using his grant award of £15,000 on funding further research on low germination stimulant sorghum. His field research is conducted in Kibos, Alupe and Mbita in western Kenya, regions where Striga is endemic. Sorghum in Kenya used as food: porridge, flour, malted & distilled beverage; animal feed; as well as for commercial uses: making wall boards, solvents, bio-degradable packaging materials, fences, etc. Sorghum is also used in making ethanol, adhesives and paper.

He works closely with farmers at grassroots level. Currently, farmers use various conventional, home-grown sanitation techniques to control the parasite such as weeding and use of herbicides, employing crop rotation, planting of resistant varieties and ‘push and pull’ strategy. However, these solutions offer moderate control efficiency because the parasite continues to expand in host range and geographical range. His research involves genome editing, a new cutting edge technique, that offers precision in deleting a defective gene, repairing it or replacing it. This research is on-going and he hopes very soon it will be available to farmers pending several regulatory approvals.

The Royal Society’s award celebrates researchers whose ground-breaking work has helped answer fundamental questions and advance our understanding of the world around us. They also champion those who have reinforced science’s place in society, whether through inspiring public engagement, improving our education system, or by making STEM careers more inclusive and rewarding. In his parting shot the humble professor, amidst this great recognition, hopes he will make people aware of its ravaging effects caused by parasitic plants, its implications on food and nutrition security, and urged governments to put in more resources to scientific research offering solutions to this challenge.