Orange fruit borer

Isotenes miserana

The adult moths are light grey, speckled with small brown marks, bell-shaped when at rest, with a wingspan of 15-25 mm. They fly with a fluttering action, mostly at night.

The scale-like eggs are laid in clusters under leaves. When fully grown the larvae are about 24 mm long, brown on top and light grey underneath, with a dark brown head capsule and a pair of brown stripes along the body. They pupate within the silken shelter formed while feeding. The pupae are brown or green-brown, approximately 13 mm long and found on the foliage.

On hatching the young larva feeds on surface cells and soon constructs a silken webbed shelter. The life cycle takes four to six weeks and successive generations occur throughout the year. There are several generations in a year but activity is less in summer. All stages can be found in winter.

Occurs widely throughout coastal Queensland.

Orange fruit borer feeds on many plants including avocado, citrus, feijoa and macadamia.

Minor and sporadic.

Orange fruit borer causes damage to feijoa. The larvae chew and burrow into the fruit generally just below the skin and often near the calyx. Young and mature fruit can be attacked. Larvae roll flower buds and young leaves together to form feeding shelters. Larvae bore into maturing and ripe fruit causing it to fall and decay, sometimes they destroy new young fruit in spring. Young larvae may penetrate fruit just before harvest, and if undetected during packing, may cause the fruit to decay during marketing.

Spray if there is an average of 10 larvae per tree.

Chemical

Spray using a recommended insecticide.

Chemical registrations and permits

Check the Australian Pesticides & Veterinary Medicines Authority chemical database and permit database for chemicals registered or approved under permit to treat this pest on the target crop in your State/location. Always read the label. Always observe withholding periods.