Bacterial wilt limits potato yields and degrades seed quality from generation to generation. First documented in Uganda in 1958, bacterial wilt is widespread in that nation, limiting yields and degrading seed quality. But little is known about the extent of the disease and the type of pathogen strains involved in the epidemics of disease.
With potatoes, bacterial wilt is not always physically apparent: the harvest can look healthy, but the crop will not be fit as a seed for the next planting season. This combination of yield and seed quality issues for potatoes translates into larger concerns about food security and boosting local incomes.
The issue is a lack of surveillance. “There has been no systematic monitoring and documentation of bacterial wilt in Uganda, so we set out to map the incidence and patterns of its movement,” said Kalpana Sharma, a pathologist with the International Potato Center (CIP).
Bacterial wilt is a seedborne disease, spreading easily from farm to farm and even country to country. Many African countries do not have measures in place – like quarantine – to prevent its spread. Furthermore, countries like Uganda do not have certified seed systems that can help with seed quality and health control issues.
As reported on potatonewstoday.com¸ Sharma and her colleagues conducted a nationwide survey to chart the prevalence and spread of bacterial wilt in Uganda, as well as the type of pathogens present. They worked from a hypothesis that the disease was moving primarily through seeds. The survey results would confirm that hypothesis.
Bacterial wilt was present in 73% of ware potato farms and 50% of seed potato farms. The movement of the disease has gone from eastern and western regions to the northern region where potatoes have been more recently introduced.