Information

Agricultural entomology: Flaky aleirode of citrus fruits

Agricultural entomology: Flaky aleirode of citrus fruits

Classification and host plants

Class: Insects
Order: Rincoti
Suborder: Homoptera
Family: Aleurodidi or Aleirodidi
Genus: Aleurothrixus
Species: A. floccosus (Mask.)

Bibliographic reference:
Phytopathology, agricultural entomology and applied biology” – M.Ferrari, E.Marcon, A.Menta; School edagricole - RCS Libri spa

Host plants: Citrus fruits.

Identification and damage

The Aleirode (or Aleurodideo white fly flaky citrus) flaky is widespread in the citrus areas of central-southern Italy, the islands and in Liguria; it is a newly introduced insect in our range.
Ladulto (about 1.5 mm long) is yellowish and has a body covered with whitish waxy powder; it differs from Dialeurodes citri by the wings which are narrower and more slender. The nymphs are characteristic for the abundant flaky interweaving of white wax threads, which protect the body.
The damages, similar to those of Dialeurodes citri, are caused by adults and juvenile stadiums; they steal sap causing the plant to decay. Neanids form colonies that can completely encrust the underside of the leaves; they also produce abundant honeydew which, together with the waxy production, also entangles the fruits and on which abundant fumages are established. The fruits, especially the tangerines, so affected appear covered with a blackish patina that depreciates them commercially.

Biological cycle

LEururothrixus floccosus overcomes winter as a 3rd or 4th age neanid; in some cases, however, it can also survive the winter as an egg.
Adults flicker from early spring; the eggs are typically laid in a semicircle or circle on the underside of the leaves. During the year 4-6 generations follow one another.

Flaky aleirode of citrus fruits - Aleurothrixus floccosus (Mask.) (Photo www.jardin-mundani.com)

Flaky aleirode of citrus fruits - Aleurothrixus floccosus (Mask.) (Photo www.jardin-mundani.com)

Fight

The fight against this phytophagus is chemical; however in nature the populations are sufficiently controlled by a Hymenoptera Aphelinis, the Cales noacki, endophagous parasitoid of the neanids, of South American origin such as the Aleurothrixus floccosus. When chemical control is necessary, it can be carried out with the same products seen for Dialeurodes citri, or it can be carried out, on the nymphs of the early stages, also with Butocarboxim which is quite selective towards the parasitoid.


Video: Growing Citrus In The Carolinas And The South (October 2021).