ABSTRACT
The harmfulness of insects presents the complex biological phenomenon determined by the action force of harmful species and response reactions of the plants. The harmfulness of insects depends, in great measure, on their selectiveness. If the pests prefer underdeveloped plants, harmfulness is less because population rehabilitation occurs. If more developed plants are primarily destroyed, the harmfulness is higher. Insects are the most dangerous pests in agriculture. The numbers of plant species damaged by a particular insect can vary. The most common damage to plants occurs without any preliminary preparation by pests; the pests generally feed on the plant as is. The damage inflicted by highly specialized pests is often comparable with that caused by polyphagous pests. Insect that damage fabrics, fur, and leather can be divided into three groups: carpet beetles, hide beetles, and clothes moths. However, the insects damage also several other materials, such as paintings, paper, and silk cocoons.
