Helping Farmers Battle Tomato Diseases
Auburn, May 18---Though
many farmers across Alabama are hoping for rain these days, too much
wet weather can mean disaster Ė or at least disease Ė for some
Tomatoes in particular
are susceptible to several devastating fungal diseases that are
common when wet weather accompanies warm summer temperatures. To
help growers protect their tomatoes from these potentially
crop-threatening diseases, Alabama Cooperative Extension System
specialists have brought TOM-CAST to the state.
Short for TOMato disease
foreCASTer, TOM-CAST, is a disease forecasting system that uses
local weather conditions to predict the development of three common
fungal diseases on tomatoes.
Dr. Edward Sikora, an
Extension plant pathologist, says the system allows growers to use a
more efficient and cost-effective fungicide spray program to control
early blight, Septoria leaf spot and anthracnose.
TOM-CAST works by using
data loggers, placed near tomato fields, to record leaf wetness and
temperature each hour. Every 24 hours, the data is analyzed and
converted to a Disease Severity Value (DSV). DSV is a numerical
representation of the rate at which disease pressure is accumulating
on a tomato crop.
A simpler and less
expensive way to gather this information, says Sikora, is to allow
AWIS Weather Services, a weather information service located in
Auburn, Ala., to estimate the DSVís for your location for a
coupled with temperatures between 70 F and 80 F, causes DSVís to
accumulate faster," says Sikora. "Eventually, they will
exceed a predetermined threshold and trigger a recommendation to
apply a fungicide. The system helps growers spray only when
Field evaluations of
TOM-CAST conducted by Sikora throughout Alabama from 1992 through
1998 have shown that growers would save three to five sprays per
crop by using the program. This not only saves the grower time and
money, but it also cuts down on the amount of pesticide released
into the environment.
TOM-CAST does not
predict outbreaks of viral or bacterial diseases, nor any other
fungal diseases, says Sikora, so it should be used in conjunction
with a weekly disease-scouting program.
For more information
about TOM-CAST, contact your county Extension office.
SOURCE: Dr. Edward
Sikora, Extension Plant Pathologist, Alabama Cooperative Extension
System, (334) 844-5502