Citrus aphids

Date: 12 Nov 2002   Author: Jianhua Mo

Citrus aphids

Species

Several species of aphids are found on citrus:

  • brown citrus aphid
  • black citrus aphid
  • melon aphid
  • spiraea aphid.

Description

  • Aphids are small (about 2 mm long), soft-bodied insects with characteristic tubular extensions to the abdomen.
  • They feed on plant sap using their sucking mouthparts.
  • Aphids have complex life cycles.
  • Adults can be winged or unwinged and females can reproduce with or without mating.
  • Aphids can build up large populations within a short period of time. However, in environments undisrupted by pesticide use, aphids are normally kept at low levels by a suite of beneficial insects.

Damage

  • Feeding by aphids distorts shoots and can transmit plant viruses.
  • They produce honeydew, which encourages the growth of sooty mould.

Monitoring

  • Randomly check young shoots in early September and late October for spring flush, and February to April for summer–autumn flush.
  • Check randomly selected young shoots, and examine five to ten young leaves from each shoot for the presence of aphids, honeydew and sooty mould.

Natural enemies

  • Parasitic wasps
  • Predatory lady beetles
  • Lacewings
  • Syrphid flies

Control measures

  • Control action is needed only when 25% or more of leaf flushes are infested and when the presence of beneficial insects on infested shoots is less than 25%.
  • Appropriate actions include spraying young growth with a specific aphicide.

ALWAYS READ THE LABEL

Users of agricultural (or veterinary) chemical products must always read the label and any Permit before using the product, and strictly comply with the directions on the label and the conditions of any Permit. Users are not absolved from compliance with the directions on the label or the conditions of the Permit by reason of any statement made or not made in this publication.

WARNING

Pesticide residues may occur in animals treated with pesticides, or fed any crop product, including crop waste, that has been sprayed with pesticides.

It is the responsibility of the person applying a pesticide to do all things necessary to avoid spray drift onto adjoining land or waterways.