Page 120 - ORNAMENTALES DEL TRÓPICO

120 Frutas del trópico

III. Pest damage
Many insects attack ornamental plants. Damage is usually caused by the insect feeding on the

plant causing direct damage or by inserting disease organisms. How insects feed on plants and

the type of damage can be useful in determining the insect causing the damage and how to

manage it. Although there are several types of insect mouthparts, the two main mouthparts

are the piercing/sucking mouthpart and the chewing mouthpart. Piercing/sucking insect have a

“tube” like mouthpart that they insert into the plant tissue in which they draw nutrients from

the plant and can also transfer disease into the plant. Insects with chewing mouthparts use

their jaws (mandibles) to grind their food. Recognizing the type of damage is the first step in

diagnosing the type of insect causing the damage.

a. Chewed leaves or flowers

Defoliation (entire leaf or large areas of the leaves removed) –large caterpillars, sawflies, snails,

slugs, grasshoppers

Shot holes (small holes in the leaves) –small caterpillars, leaf beetles

Margins notched (notches removed along the margin of the leaves)– weevils

Skeletonization (leaf tissue removed between the leaf veins) –beetles, caterpillars

b. Discolored leaves or flowers

Stippling (tiny dots on the upper leaf surface) –mites, lace bugs, plant bugs, leafhoppers

Streaking (discolored streaks) –thrips

Mining (tunnels within the plant tissue of the leaf) –leafminers

Yellowing –aphids, mealybugs, whiteflies

Universidad Autónoma de Chiapas