All about potatoes.pdf - Vegetableipmasia.org

6.
INSECT ECOLOGY
• Some natural enemies in the parasitoid and predator groups are caught, as they
are also attracted to yellow.
To lessen these drawbacks, do not install yellow traps continuously. Install and
remove every other week. Traps should be removed when natural enemy
populations are increasing.
Insect pests can be removed manually when their populations are not too high. For
this to be effective, it must be done in an organized, thorough and timely manner.
Any pests collected should be destroyed. The drawbacks of this method are that it is
time consuming and labor intensive, and difficult to do with pest species that actively
move around.
6.6.3 Chemical control
A. Introduction
PESTICIDES ARE NOT MEDICINES, BUT POISONS THAT CAN KILL ANY KIND
OF LIVING ORGANISM. Pesticides are generally killers, and are used extremely
inappropriately when applied once a day or every other day. In the rainy season,
some farmers even spray their crops twice a day. Farmers often apply a mix of
several types of pesticide. Frequencies of an average of 15 times per cropping
season have been recorded in certain potato-growing areas in Indonesia.
The main reasons farmers say they use pesticides are that they are easy to use, and
that the results are immediately apparent as many insects are visibly killed instantly.
The improper use of pesticides, however, makes potato production costs very high.
In Indonesia, about 27% of the total costs for production inputs are spent buying
pesticides. When farmers see insects or symptoms of pests or disease, they
immediately assume they should spray their crop with pesticide. In the end, the
pesticides cause more problems than they resolve, as resistance to pesticides
develop and natural enemies are killed.
B. Pesticide types
Chemical pesticides can be categorized in various ways as described below.
Based on their intended targets:
• Insecticides are pesticides intended to kill insects.
• Herbicides are pesticides used to kill off weed growth. Generally, they kill weeds
by destroying plant tissue or accelerating growth.
• Fungicides are pesticides aimed at fungi. Many contain sulfur or copper.
• Rodenticides are used to kill rodents (rats and mice). Several of them are
extremely toxic to other mammals.
• Nematicides are pesticides used to kill nematodes (tiny worms).
• Acaricides are pesticides used for killing mites.
Based on their formulations:
• Emulsifiable Concentrates (EC): Emulsifiable concentrates are thick solutions of
active ingredients in oil that contain detergent-like emulsifiers that allows the thick
solution of active ingredients to be diluted in water to form a solution for spraying
in the field. The important components of EC formulations are the active
ingredients, organic solvents and emulsifiers. Mineral oil solvents are used.
• Water-Soluble Concentrates (WSC) / Soluble Concentrates (SC): These
pesticides dissolve completely in water. Their active ingredients might dissolve in
A HANDBOOK TO THE ECOLOGY AND INTEGRATED MANAGEMENT OF POTATO 35