Mealybugs

Mealybugs are fairly common. Their body is covered by a layer of white waxy filaments. You can find them on all kinds of plants, both ornamental and greenhouse vegetables. What we call mealybugs is in fact a group of several different species. All of them have their body covered by white waxy filaments but they differ in appearance from one another in the length of their (tail) hairs, the pattern of stripes on their back and in the color of their body. Most species lay eggs in a mass of white wax threads, tens to hundreds of eggs together. Out of those only a minor part will develop into new mealybugs, most of them die in an early stage. Some species do not produce egg masses; eggs are kept in the mother's body until hatching.  Prior to oviposition usually mating is necessary, however not for all species. Mealybug males look very different from females; as adults they are much smaller and winged. They live only a few days and during that time they will have to find a female for mating.

For biological control of mealybugs, it is important to know which species is present in order to be able to make a correct choice of the natural enemy that has to be deployed.

Mealybugs are mainly a pest in tropical ornamental plants, but they can also give fruit damage in for instance tomatoes or egg plant. They suck plant juices. That causes cosmetic damage, but also reduces growth and leads to deformity of the leaf. It may happen that mealybugs cause withering of complete stems of eg. tomato, reducing fruit development and finally death of the plant. 

All mealybugs produce sticky honeydew. This ensures that the plants become sticky ("fat"). On the honeydew  the black sooty mold fungus can start growing; This hinders photosynthesis and is therefore indirectly harmfull to the plant.

mealybug characteristics:

  • body covered with white waxy filaments
  • species differ in length of filaments, pattern on their back and body color
  • in greenhouses, horticulture and vegetable production
  • on many different plants
  • pretty much honeydew

mealybug damage

  • honeydew
  • inhibition of growth
  • malformation growing tip
  • malformation leaves

PRODUCTS AGAINST MEALYBUG:

against citrus mealybug:

ANAGYRUS pseudococci; parasitoid

CRYPTOLAEMUS montrouzieri, adults; coccinellid

CRYPTOLAEMUS montrouzieri, larvae; coccinellid

LEPTOMASTIDEA abnormis; parasitoid

LEPTOMASTIX dactylopii; parasitoid


against longtailed mealybug:

ANAGYRUS fusciventris; parasitoid

CRYPTANUSIA aureiscutellum; parasitoid

CRYPTOLAEMUS montrouzieri, larvae; coccinellid


against obscure mealybug:

ACEROPHAGUS maculipennis; parasitoid

CRYPTOLAEMUS mmontrouzieri, adults; coccinellid

CRYPTOLAEMUS montrouzieri, larvae; coccinellid

LEPTOMASTIX epona; parasitoid


against solanum mealybug:

LEPTOMASTIX epona; parasitoid