Category: Knowledge
Date published: June 06, 2019

Infestation Levels in Tomato Crops: A Look at the Top Four

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Tomato plants are popular targets for a wide range of insects and mites. The pests that cause the biggest problems vary from one country to another, and even between regions. Nevertheless, all growers need to be able to tackle the top four pests: spider mite, whitefly, aphids, and caterpillars.

Two-spotted spider mite Tetranychus utricae

Spider Mite

Spider mite is an enemy to many crops around the world. These mites are tiny spider-like creatures (arachnids) that reproduce very quickly and can quickly become resistant to chemicals. The spider-mite family is huge, but it is the two-spotted spider mite (Tetranychus urticae) that causes most damage in both greenhouse crops and outdoor crops. Fortunately, two-spotted spider mite has several natural enemies: predatory mites, gall midges, and predatory bugs.

Greenhouse whitefly Trialeurodes vaporariorum Adult Illustration Greenhouse whitefly Trialeurodes vaporariorum adult

Whitefly: The Source of Multiple Problems

There are also many different kinds of whitefly. Tobacco whitefly (Bemisia tabaci) is a problem all over the world. In greenhouses, greenhouse whitefly(Trialeurodes vaporariorum) also forms a significant challenge.

Predatory mites, parasitic wasps, predatory bugs, and predatory beetles are natural enemies of whitefly, but parasitic fungi can also help tackle this pest. Rollertraps are also a useful tool in the battle against whitefly: they can help in the capture and removal of adult whitefly.

Potato aphid Macrosiphum euphorbiae

Aphids and Mealy Bugs

And then there are aphids; these are a common problem in tomato crops. The different kinds of aphids all require different approaches, so it is important to know which species you are dealing with. The aphids remove nutrients from the plant and disturb the hormone balance.

Alongside aphids, mealy bugs are also increasingly causing problems in tomato crops grown under glass. Their existence and movements are hard to detect, making control a complicated matter. Good to know: mealy bugs were among the very first pests to be combated with natural enemies - ladybirds.

Larva of the Tomato leafminer Tuta absoluta

Caterpillars

Lastly, there's the problem of caterpillars – the larvae of moths. In greenhouse-grown and outdoor tomato crops, Tuta absoluta represents a particularly tricky problem. In subtropical regions, species such as Spodoptera, Helicoverpa, and Duponchelia often cause issues.

It is a good idea to capture adult moths using pheromone traps. You can also release natural enemies in the form of predatory bugs and parasitic wasps.

These top four pests are found worldwide.