Kirvat

Kirvat, or aphids, are small, soft-bodied insects belonging to the superfamily Aphidoidea within the order Hemiptera. They occur in many species and colors and are common pests on a wide range of garden and crop plants. These insects feed by inserting their piercing-sucking mouthparts into the phloem to extract sap, which supports rapid population growth under favorable conditions.

Aphids vary in size from about 1 to 3 millimeters and may be winged or wingless. They use specialized mouthparts to access plant vascular tissue and can form dense colonies on new growth, buds, or undersides of leaves. Feeding produces honeydew, a sugary excretion that can attract ants and promote sooty mold, reducing photosynthesis and plant vigor.

Most aphids reproduce asexually through parthenogenesis during spring and summer, generating many generations quickly. Some species produce winged forms to disperse to new hosts when conditions deteriorate or overcrowding occurs. In temperate regions, many populations overwinter as eggs on perennial plants or as sheltered forms on hosts.

Ecologically, kirvat are important as pests and as prey for predators. They are also vectors for plant viruses, including luteoviruses and potyviruses, contributing to disease spread in crops such as fruit trees, vegetables, and ornamentals. Economic impact can be substantial in commercial agriculture and horticulture.

Management focuses on monitoring and an integrated approach: encouraging natural enemies (lady beetles, lacewings, hoverflies, parasitoid wasps), applying cultural controls (removing infested material, plant spacing to improve airflow), and using targeted insecticides or horticultural oils when necessary.