Plant Diagnostics

Mealybug - Pseudococcidae family

Description

Characteristically mealybugs are covered in white granular or cotton-like wax. Mealy bug bodies are always soft and the females are oval and flat with distinct segmentation often visible in the wax. Eggs are usually laid in a white cottony material underneath the female. Widespread in greenhouses and indoor plants; not an outdoor problem. Depending on temperature, one generation can develop every 1-3 months.

Damage

Mealybugs produce honeydew, which is one of the first signs of feeding by these insects. Another sign is ants feeding on the honeydew. Common plant symptoms include distorted growth and premature leaf drop.

Cultural Controls

Inspect new plant material and return infested plants to supplier. Destroy heavily infested greenhouse plants. Remove excess soil and compost piles from growing areas to prevent alternative infestation sites. Mealybug destroyers (beneficial beetles) can be effective in controlling populations in some situations. For this to work, growers must be willing to tolerate a low level infestation of both pests and beneficial insects on plants.

Remarks

Chemical control can be difficult because of the protective wax covering these insects. Insecticidal soaps in contact sprays are affective against the mealybug crawler stage with thorough coverage. Use insect growth regulators when beneficial insects are present. You will need 2-3 treatments at 10-14 day intervals to get good control, as eggs and adult stages are protected from most insecticides.

Chemical Controls

Acephate
Signal Word: Caution
Pesticide Class: Organophosphate
Azadirachtin
Signal Word: Caution
Pesticide Class:
Beauveria bassiana
Signal Word: Caution
Pesticide Class: Microbial
Bifenthrin
Signal Word: Caution
Pesticide Class: Synthetic pyrethroid
Buprofezin
Signal Word: Caution
Pesticide Class: Insect growth regulator
Carbaryl
Signal Word: Caution
Pesticide Class: Carbamate
Chlorpyrifos
Signal Word: Danger
Pesticide Class: Organophosphate
Clothianidin
Signal Word: Caution
Pesticide Class: Neonicotinoid
Clothianidin+Bifenthrin
Signal Word: Caution
Pesticide Class: Neonicotinoid, Synthetic Pyrethroid
Cyfluthrin
Signal Word: Caution
Pesticide Class: Synthetic pyrethroid
Deltamethrin
Signal Word: Caution
Pesticide Class: Synthetic pyrethroid
Dimethoate
Signal Word: Warning
Pesticide Class: Organophosphate
Dinotefuran
Signal Word: Caution
Pesticide Class: Neonicotinoid
Fenpropathrin
Signal Word: Warning
Pesticide Class: Synthetic pyrethroid
Fluvalinate
Signal Word: Warning
Pesticide Class: Synthetic pyrethroid
Imidacloprid
Signal Word: Caution
Pesticide Class: Neonicotinoid
Imidacloprid+Bifenthrin
Signal Word: Caution
Pesticide Class: Neonicotinoid, Synthetic pyrethroid
Imidacloprid+Clothianidin
Signal Word: Caution
Pesticide Class: Neonicotinoid
Imidacloprid+Cyfluthrin
Signal Word: Caution
Pesticide Class: Neonicotinoid, Synthetic Pyrethroid
Insecticidal soap
Signal Word: Caution
Pesticide Class: Insecticidal soap
Kinoprene
Signal Word: Caution
Pesticide Class: Insect Growth Regulator
Malathion
Signal Word: Warning
Pesticide Class: Organophosphate
Permethrin
Signal Word: Caution
Pesticide Class: Synthetic pyrethroid
Pyrethrins
Signal Word: Caution
Pesticide Class: Botanical
Thiamethoxam
Signal Word: Caution
Pesticide Class: Neonicotinoid
Ultra-fine oil
Signal Word: Caution
Pesticide Class: Horticultural oil

Locations Affected

flowers, fruit, leaves, needles, roots, stem

Plant Environment

greenhouse

Scouting Season:

January - Early , January - Mid , January - Late , February - Early , February - Mid , February - Late , March - Early , March - Mid , March - Late , April - Early , April - Mid , April - Late , May - Early , May - Mid , May - Late , June - Early , June - Mid , June - Late , July - Early , July - Mid , July - Late , August - Early , August - Mid , August - Late , September - Early , September - Mid , September - Late , October - Early , October - Mid , October - Late , November - Early , November - Mid , November - Late , December - Early , December - Mid , December - Late

Plants Affected


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