News Crop Protection Inputs
Growers urged to keep an eye out for mealybugs

Specialists are urging growers to inspect for mealybugs in shipments of tropical foliage and succulent plants entering greenhouses.

A recent report from the University of Massachusetts Amherst, highlights their concern for the possibility of this harmful pest being brought into greenhouses.

Geoffrey Njue, Extension Specialist from the UMass Extension Greenhouse Crops and Floriculture Program, encourages growers to isolate their new plants in a separate area away from the main greenhouse.

The small oval-shaped insects feed on a wide range of host plants. Mealybugs plant fluids using their mouth and inject saliva into plant tissue, causing stunted growth, yellowing of leaves and distortion. They also excrete sticky honeydew that serves as a growing medium for black sooty mold fungi.

Mealybugs have distinctive white, waxy filaments protruding from their bodies. The adult females are covered with white powdery, waxy secretions, while the males are short-lived winged insects that do not feed.

Besides their initial crawling stage, mealybugs rarely move, but this does not entail that they can’t circulate within greenhouses.

Njue encourages workers in greenhouses to be educated on the importance of sanitation practices, as mealybugs can spread when they are handling plants.

It is recommended that a hand lens or magnifying glass be used to look for the insect, focusing on the growing tips and areas where the leaves attach to the stems. Yellow sticky cards are not effective as adult male mealybugs can fly.

If the insect is found, the plant should be treated with a labeled insecticide before introducing them into the greenhouses. Multiple applications and thorough coverage may be required, read and follow label directions.

More information can be found on the UMass website.

(Source: University of Massachusetts Amherst)