Computer Figures Stored-Grain Insect
Farmers who store their own grain can make better pest
management decisions by using an ARS-developed expert system. Biologist Paul
Flinn shows how the Stored Grain Advisor can reduce insecticide applications
and lessen the chance that grain will become infested while in storage.
Next July, a Kansas farmer stores wheat with a moisture content of 12
percent and a temperature of 90° F in a grain bin.
After entering the storage information into his personal computer, a program
called Stored Grain Advisor (SGA) indicates he will need to be wary of damaging
insect infestations if he plans to store the grain past mid-September.
SGA helps the grain manager select the most appropriate control methods.
According to the scenario, the program recommends sampling for insects 1 month
after harvest and cooling the grain with aeration in September to possibly
avoid a need to fumigate with an insecticide.
"We developed the SGA program as a decision-making aid that should help
grain managers refrain from using pesticides unnecessarily, while maintaining
quality in their product," says Paul W. Flinn, an ARS biologist at the
U.S. Grain Marketing Research Laboratory in Manhattan, Kansas.
The software, available to farmers and grain elevator operators, is designed
to run under Microsoft Windows on an IBM-compatible personal computer.
It will be distributed this summer through extension programs at Kansas
State, Oklahoma State, and Montana State Universities.
SGA uses computer models to predict insect population growth, degradation of
insecticides, and the effects of grain fumigation.
Besides serving as a management tool, SGA is also an educational tool. Grain
managers can get information on how to sample grain for insect pests and how to
identify the insects they find. An insect identification icon allows the user
to view pictures of 16 of the most damaging insects in stored wheat, along with
descriptions of the pests and the damage they inflict.
Another SGA module graphically predicts how different management
choicesfor example, time of fumigationaffect population growth of
Flinn and ARS entomologist David W. Hagstrum confirmed the accuracy of SGA
using data from some 50 different grain bins in Kansas and Oklahoma. In each of
3 years, they sampled grain monthly from June through January for insects,
temperature, moisture, test weight, and insecticide residue. Insect pests they
most frequently saw were rusty grain beetle, lesser grain borer, red flour
beetle, and saw-toothed grain beetle.
The model was correct 80 percent of the time in predicting which bins would
become infested with low, moderate, or high insect densities, and it was not
biased in over- or under-predicting.
Rarely did wheat become infested with insects when it was stored at moisture
levels of less than 10 percent and aerated to less than 68° F early in the
Future enhancements the scientists plan for SGA include addition of other
grains besides wheat and the ability to forecast economic consequences of
different management actions. By Ben Hardin, ARS.
W. Flinn is in the USDA-ARS
Research Unit, U.S. Grain Marketing and Production Research Center, 1515
College Avenue, Manhattan, KS, 66502; phone (785) 776-2707, fax (785) 537-5584.
"Computer Figures Stored-Grain Insect Risk"
was published in the June 1995 issue of
Agricultural Research magazine.