Agriculture Reference
In-Depth Information
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mechanical control—use of temperature and humidity control, and
soil sterilization by heat
•
chemical control—use of chemicals for specific pest outbreaks and
chemical soil sterilization.
The major elements of the environment can be manipulated in a green-
house to prevent pathogens from building up rapidly enough to damage crops.
2.
On Stored Food and Feed
As in greenhouses, the environment in storage facilities can be manipu-
lated. To achieve disease control in storage, you must have good sanitation in
the storage facility before storage, make sure that the crop is relatively patho-
gen-free at time of storage, and provide adequate ventilation to control the
buildup of temperature and humidity.
Ideal storage conditions vary from crop to crop. Favorable environmental
conditions must be maintained to ensure the quality of the product being
stored. However, if these same conditions favor a rapid development of plant
diseases, the two factors must be weighed carefully.
3.
Outdoors
The main methods for control of plant disease outdoors include:
•
host resistance
•
cultural control
•
mechanical control
•
sanitation
•
chemical control.
a.
Host Resistance
The use of disease-resistant varieties is usually one of the most effective,
long-lasting, and economical ways to control plant disease, if the resistant
varieties are otherwise acceptable. Resistant varieties have long been one of
the major factors in maintaining high levels of crop productivity in the United
States. For certain crops, 95 to 98 percent of the acreage grown is planted
with varieties that are resistant to specific diseases.
In some cases, resistant varieties are the only way to ensure continued
production. For many diseases in low-value forage and field crops, for exam-
