Yates Mavrik Insect & Mite Spray - Concentrate
Controls a broad range of insect and mite pests.
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Lepidoptera / Noctuidae
Helicoverpa armigera conferta
(Previously known as Heliothis armigera)
What are Tomato Fruit Worms?
Found throughout New Zealand, the tomato fruit worm is a caterpillar that chews holes into flower buds and bores its way into tomato fruit. They also chew sections out of newly unfolding leaves, causing growth to become stunted. They can cause a lot of damage and defoliation when their population builds up.
The name of these little blighters can be a little misleading, because tomato fruit worms actually feed on a very wide range of host plants.
To add to the confusion, when feeding on tomato fruit, they’re commonly referred to as ‘tomato fruit worm’; but when feeding on sweetcorn they’re commonly called ‘corn earworm’. Overseas, these names describe different species, but here in NZ it’s exactly the same miscreant causing the trouble in both cases.
The caterpillar that causes all the damage is the larva of a nondescript-looking nocturnal moth. Because these ochre-brown moths are usually found in the tropics, their range in NZ is partly constrained by frost. Unfortunately, the moths are capable of long-distance flight so they'll rapidly expand South during periods of warm weather.
Caterpillars range in colour from light green, to red, to almost black. They often have light-coloured stripes along their backs and sides. These pests pupate below ground to make it through the winter, before emerging as adult moths between November and March.
Symptoms
When feeding on tomato or citrus fruit, caterpillars will usually hide under or around the stalks and calyx. Holes chewed into the fruit will also most likely be close to the calyx.
Frass (caterpillar faeces) is usually visible in or near the feeding holes. These granular droppings can be brown or green in colour.
Heavy infestations of caterpillars can cause substantial leaf damage or defoliation of trees.
Plants may become yellow and exhibit stunted growth as an effect of these caterpillars feeding.
In sweetcorn, the most serious damage occurs when the larvae chew their way inside the husks and begin munching through the corn kernels and silks. To add insult to injury, the caterpillars leave behind moist cast-off skins that encourage fungi to grow, creating an opportunity for diseases to get established inside corn cobs.
Plants Impacted
- Tomatoes
- Capsicum
- Potato
- Corn / Maize
- Beans
- Peas
- Pumpkins / Squash
- Citrus
- Conifers
- Pinus radiata
- Flax
Yates Mavrik Insect & Mite Spray - Ready to Use
Controls a broad range of insect and mite pests, yet will not interfere with honey bees once the spray has dried.
Yates Nature's Way Pyrethrum Natural Insect Spray - Concentrate
Controls a wide variety of insect pests on vegetables, flowers and ornamentals.
Yates Nature's Way Fruit & Vegie Gun - Ready to Use
A natural insecticide for use on edibles, roses, indoor plants and outdoor ornamentals. It is fast acting and kills a wide range of pests.
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