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Description
The citrus mealybug is a soft-bodied, oval, and pink insect
approximately 1/8 inch long when mature. The body after the
first growth stage is covered by white, waxy material, with
short filaments radiating from the margins of the body. Adult
male mealybugs are tiny two-winged fly-like insects. The immatures
or nymphs resemble the adult female except they are smaller.
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version
Figure 1. Long-tailed Mealybugs on Palm
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Life
History
The citrus mealybug or short tailed mealybug is the most common
species found on ornamental plants. It has an extensive host range
and prefers soft-stemmed and succulent plants such as croton, gardenia,
begonia, oleander, Coleus, Fuchsia, and cactus. Other hosts include
citrus, geranium, orchids, poinsettias, ivy, dracaena, and chrysanthemums.
Adult female mealybugs lay up to 300 - 600 eggs in a compact, cottony,
waxy sack beneath the rear end of their body. Egg laying continues
for 1 - 2 weeks with the female dying as soon as egg laying ceases.
The egg sacks are found primarily in the axils of stems and leaves,
but may be on other parts of the plant. Egg hatch occurs in about
10 days and the nymphs or crawlers begin actively searching feeding
sites. Female crawlers progress through 3 stages with a generation
taking about a month or up to a year depending on temperature. Under
normal greenhouse conditions the lifecycle is 1 - 2 months. Shortly
after the crawlers begin feeding they secrete a white waxy material
which covers their body. The crawlers move about the plant, but
are usually very sluggish in their activity. The citrus mealybug
prefers humid conditions, but shown its adaptability by being successful
on cacti under semi-arid conditions
Damage
Mealybugs are sap-feeding insects resulting in a distorting, stunting,
and yellowing of the foliage. Like other sap-feeding insects, mealybugs
excrete large quantities of honeydew which promotes sooty mold and
ants
Nonchemical
Control
Cultural control includes dislodging of mealybugs with water sprays,
and using plants less preferred by the insect. Practice good sanitation
by checking new plants carefully and dispose of infested plants.
Biological control includes the use of Australian lady beetle, green
lacewings (predators) and a wasp parasite, Leptomastix dactvlopii.
Chemical
Control
Insecticidal sprays may be applied if mealybug populations are heavy.
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