Woodlice

The woodlice Mealybugs are phytophagous insects that are widespread throughout the world, especially in tropical and subtropical areas. In these warm areas, where the climate is favorable almost 365 days a year, mealybugs, like many other insects and mites, do not hibernate, producing several generations throughout the year.

Under optimal temperature and humidity conditions (25ºC and 60%) the egg-to-adult development can last just over 20 days.

Cochineal reproduction can be sexual; the male usually fertilizes several females.

Mealybugs and soft-shelled scale insects are a major problem for outdoor crops. Carried from one place to another by the wind, they often cause continuous infestations. Furthermore, scale insects are highly polyphagous, able to take refuge on various alternative plants such as weeds, ornamentals, and fruit trees when crops are unavailable.

In indoor crops, the main vector for the transmission of mealybugs is man.

These phytophagous insects are widespread throughout the world, especially in tropical and subtropical regions. In these warm areas, where the climate is favorable almost 365 days a year, mealybugs, like many other insects and mites, do not hibernate, producing several generations throughout the year.

Under optimal temperature and humidity conditions (25ºC and 60%) the egg-to-adult development can last just over 20 days.

Cochineal reproduction can be sexual; the male usually fertilizes several females.

Woodlice Video

Mealybugs and soft-shelled scale insects are a major problem for outdoor crops. Carried from one place to another by the wind, they often cause continuous infestations. Furthermore, scale insects are highly polyphagous, able to take refuge on various alternative plants such as weeds, ornamentals, and fruit trees when crops are unavailable.

In indoor crops, the main vector for the transmission of mealybugs is man.

The insects appear on stems, branches, leaf axils, leaf petioles, and even among the buds. The damage caused by these phytophagous insects is due to the larvae and adult females sucking the sap. Like whiteflies and aphids, they are homopterans with piercing-sucking mouthparts.

The affected plant parts yellow due to lack of nutrients and slowly die. Mealybugs also typically excrete large amounts of honeydew. The damage caused by the excessive accumulation of this substance on the leaves is a reduction in photosynthetic capacity. Furthermore, it can block the opening of the stomata, significantly reducing carbon dioxide assimilation and decreasing transpiration.

Control method

Outdoors, controlling host plants (weeds, ornamentals, fruit trees, etc.) will be crucial for true prevention.

Although identifying these insects is fairly easy, due to the resistance these insects develop to insecticides, especially soft-shelled mealybugs, traditional control is very complex.

Applying concentrated neem extracts appears to be quite effective in controlling small populations of mealybugs. Soft scale insects, which are quite common in outdoor crops in subtropical areas, are somewhat more difficult to control.

Biological control is effective when the pest is widespread and/or its location on the plant makes treatment difficult. For best results with biological applications, a combined release of a predator and a parasite, such as a predatory beetle, should be carried out. Cryptolaemus montrouzieri and the parasitic wasp Leptomastix dactylopii.