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Life on the land in Australia

RARE FRUIT INSECT PESTS

Helopeltis in rare fruit

David Astridge and Harry Fay

Helopeltis sp. are also known as Tea mosquito or Mirid bugs.

Adult (left) and nymph of Helopeltis, also known as Tea Mosquito or Mirid Bug
Adult (left) and nymph of Helopeltis, also known as Tea Mosquito or Mirid Bug.

Description

Adult

Adults are 6.5-8.5 mm long, dark brown to reddish brown but with an orange thorax. A dark pin-like process protrudes from the centre of the thorax. The legs are long and fragile, resembling those of a mosquito.

Immature stages

The eggs are white and elongated and about one millimetre long. Later instar nymphs are similar in appearance to the adults, although wingless and orange-brown in colour. Legs are spindly and black.

Life history

The eggs are laid in plant tissue singly or in small groups. The stems and petioles of young leaves are the main oviposition sites. Eggs take about a week to hatch. Nymphs feed on young leaves and shoots, or other developing plant parts. There are five nymphal instars, with a total development period of 10-16 days. Adults can live for several weeks, and females may lay 30-50 eggs during this time.

Distribution

Northern Queensland, but the distribution is poorly known.

Host range

Cocoa, tea, cashew, avocado, mango, guava, passionfruit and sweet potato.

Management

Importance

Tea mosquito bugs are a serious and spasmodic pest of cashews.

Damage

The sucking activities of tea mosquito bugs result in young leaves of cashews becoming distorted with lesions along the main veins. Bunched terminal growth develops after severe attack. Developing apples and nuts can show brown sunken spots. Damage is easily confused with that caused by fruitspotting bugs.

Action level

Examine five trees at six widely spaced locations throughout the crop. Spray when damage is first noticed on developing fruit.

Control methods

Biological

Green tree ants, once established in an orchard and correctly managed, can suppress tea mosquito damage. NOTE; Care should be observed with green tree ants as they can also become a pest, especially in wet environments. The ants have symbiotic relationships with sap sucking honeydew producing insects such as mealy bug and scale Green tree ants may also cause problems due to aggressive behaviour to beneficial insects and fruit pickers at harvest.

Chemical

Prompt spray application is required to prevent serious damage.

Recommended chemicals

No registered chemicals are available. Note: This information was correct at the time of publication. However, it is the user’s responsibility to ensure that registered agricultural chemicals are used in accordance with legal requirements. (See Further information). Always read the label.


October 7th, 2010
Topic: AGRICULTURE, FOOD DRINK, FRUIT VEG SMALL CROPS, INSECTS REPTILES, Moths & Nymphs, PESTS DISEASES BACTERIA VIRUSES, PLANTS CROPS WEEDS Tags: , , , , , ,

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