46th TWC, Tob. Work. Conf., 2014, abstr. 73

Harvester modification to reduce mechanical transmission of R. solanacearum

Clemson University, Department of Entomology Soils and Plant Sciences, Pee Dee Research and Education Center, Florence, SC, USA

Mechanization both in leaf (multipass harvester) and flower (topping) removal has contributed to the spread and severity of bacterial wilt in North and South Carolina. When a mechanical harvester removes an infected leaf the bacterium can contaminate defoliators, gleaners and leaf guides. The contaminated harvester components can then move the bacterium to adjacent healthy plants, increasing the severity of disease. The objectives of the present trial were to evaluate a modified harvester designed for the ability to reduce stem injury and transmission of the bacterium to healthy stem or leaf scars and to evaluate the application of C10 fatty alcohol to defoliators, gleaners and leaf guides for suppression of transmission of the bacterium. Stationary rubber leaf guides on the multi-pass harvester were replaced with a continuous rubber belt that moved with the stem as the harvester moved down the row. Tobacco stalks contained less stem bruising and reduced mechanical transmission and infection of stalk tissues when a continuous belt replaced stationary leaf guides in both years of the study (P = 0.05). The use of C10 fatty alcohol disinfectants applied to defoliators, gleaners and leaf guides during the harvesting process significantly reduced the transmission of R. solanacearum in both years of the study (P = 0.05). (Reprinted with permission)