Staff Reporter
The Tobacco Research Board (TRB) has intensified its efforts to tackle the growing threat of Fusarium Wilt and Root Rot (FWRR), a destructive fungal disease that continues to affect tobacco farmers across Zimbabwe.
Speaking to this publication yesterday, TRB Plant Pathologist, Mike Maranda, said the board wasworking on several interventions to reduce the impact of the disease.
“We are currently testing several fungicides which will be made available to farmers in the next tobacco season. Our focus is also on developing resistant varieties through a breeding programme aimed at tackling both FWRR and Black Shank,” he said.
Maranda warned that tobacco farmers should be alert and monitor their fields closely for signs of the disease.
“Farmers need to regularly inspect their crops. Typical symptoms of FWRR include yellowing and drying of leaves, stunted growth, defoliation, and eventually plant death. In some cases, you will notice symptoms only on one side of the plant or leaf midvein.
“A distinct chocolate brown or purple discolouration in the vascular tissue running from the taproot to the top of the plant is a tell-tale sign. The stem may even bend over at the bud, creating a crook-neck effect. Infected plants dry out and die, with leaves curing on the stalk rather than rotting,” Maranda said.
FWRR is caused by soilborne fungi from the genus Fusarium.
More than 18 Fusarium species are associated with the disease globally. At least seven was identified in Zimbabwe, including F. nicotianae, F. falciforme, F. solani, F. longifundum, and F. chlamydosporum.
Head of Plant Health and Agricultural Resilience, Dr Charles Karavina, said the disease thrives under specific environmental and management conditions.
“This disease flourishes in warm, humid climates and is particularly aggressive in sandy-loam soils. It becomes worse with monocropping and poor sanitation practices such as leaving infected stalks in the field and moving contaminated soil or water between fields,” he said.
He emphasised the importance of integrated disease management.
“We are urging farmers to rotate their crops, maintain strict hygiene in their fields, and make use of resistant tobacco varieties once they become available. These steps are key to reducing the spread and severity of FWRR,” said Dr Charles Karavina.
The TRB continues to lead research and farmer engagement efforts to protect the country’s tobacco crop from emerging disease threats.
