Soybean rust, a fungal pathogen of soybean, can overwintered on kudzu. Kudzu, a tropical legume, is the main overwintering host for the pathogen in the United States. Soybean rust survives on kudzu along the Gulf Coast and down into central Florida when winter temperatures are mild and no significant freeze events occur.
The presence of the pathogen in Alabama does not necessarily mean there will be a significant outbreak of the disease. However, it does suggest the potential for an epidemic later in the season is possible. Other factors, including rainfall during the growing season, average daily temperatures, and the occurrence of early season tropical storms, will dictate how much producers should fear soybean rust.
In south Alabama, 2022 winter surveys did not uncover any soybean rust-infected kudzu that had successfully overwintered. Monitoring for the disease will continue on kudzu and eventually soybean fields as the season progresses Soybean rust alerts will made available by Alabama Extension professionals if it appears the disease is becoming a problem for soybean growers in the state.
Soybean rust overwintering.
Source : aces.edu