Occurrence and Management of Tomato Canker
Principal Investigators: Margaret Tuttle McGrath, Dept. of Plant Pathology, Riverhead; Dale D. Moyer, Vegetable/Potato Specialist, CCE Suffolk County; W. Alan Erb, Vegetable Specialist, CCE Lake Plains Vegetable Program; Ted Blomgren, Vegetable Specialist, CCE Capital District
Cooperators: Mary Hausbeck, Dept. of Plant Pathology, Michigan State University; Charles D. Bornt, Vegetable Specialist, CCE Lake Plains Vegetable Program; Abby Seaman, Area Vegetable IPM Specialist, WNY; tomato growers in each participating county
Bacterial canker recently has been one of the most important disease problems on tomatoes grown in New York. The goals of this project were to determine the sources of bacterial canker in New York and to examine the impact on disease development of management practices used in commercial settings. Canker was not observed in any of the fields, which was very surprising considering the regularity with which this disease has been occurring. Possible explanations include: 1) conditions were not favorable for canker development, 2) seed has been the source and the seed lots the cooperating growers used were pathogen-free, and 3) growers used effective management programs in 2000. However, none of these explanations seems highly likely. Valuable information was gathered during discussions with growers about implementation of recommended management practices for canker. Growers also benefited. Several decided to start using practices they had not been using. In sharp contrast with canker, bacterial spot was widespread in 2000. Infested seed is a possible source of the bacteria causing spot. Additional work is needed to obtain a better picture of the occurrence and manageability of canker and other bacterial diseases of tomatoes in New York and to investigate possible sources of the pathogens. Additional work is warranted because reducing the occurrence of canker and other bacterial diseases of tomatoes would improve grower profitability, decrease use of copper pesticides, and enable growers to resume using TOM-CAST which also can decrease pesticide use. TOM-CAST, a forecasting system for scheduling fungicide applications for early blight, was an important component of the tomato IPM program in New York until canker became important.