Hr. Dillard et al., AN ASSESSMENT OF FUNGICIDE BENEFITS FOR THE CONTROL OF FUNGAL DISEASES OF PROCESSING TOMATOES IN NEW-YORK AND NEW-JERSEY, Plant disease, 81(6), 1997, pp. 677-681
Concurrent studies on the benefits of fungicide use for control of fun
gal diseases of processing tomatoes were conducted in New York and New
Jersey in 1993 and 1994. Fungicides (chlorothalonil at 2.5 kg/ha or m
ancozeb at 1.68 kg/ha) were applied at 7-, 10-, or I l-day intervals t
o processing tomatoes for control of anthracnose caused by Colletotric
hum coccodes, early blight caused by Alternaria solani, and Septoria l
eaf spot caused by Septoria lycopersici. The New Jersey trial included
an additional treatment using the disease-warning system TOM-CAST. Al
l fungicide treatments significantly reduced foliar disease severity (
in New York) and anthracnose incidence (New York and New Jersey) in th
e 2 years of study. Yield of usable fruit was significantly increased
by all fungicide treatments with the exception of the TOM-CAST treatme
nt using the cultivar Brigade in 1994 in New Jersey. In New York, usab
le yield and financial benefit were consistently the highest in plots
treated with chlorothalonil on a 7-day interval. In New Jersey, the hi
ghest usable yields and the greatest financial benefits occurred in th
e chlorothalonil 7- and 10-day interval treatments in 1993. At both lo
cations, the yield and financial benefit associated with the fungicide
treatments was primarily due to suppression of anthracnose and other
fruit rots. Suppression of foliar diseases was less important.