[Edited_by_A._Ciancio,_C.N.R.,_Bari,_Italy_and_K.(Bookos.org)

CITRUS PEST MANAGEMENT IN ITALY
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species of ants in Sicilian citrus orchards. Interesting hints could come from the
evaluation of the effect of joint releases of predators, such as for example
C. bipustulatus, which has an impressive “cleaning effect” on dense colonies, mostly
on branches and trunk, and is less sensitive to high temperatures.
2.2. Aspidiotus nerii Bouché
Commonly known as Oleander scale, A. nerii (Hemiptera: Diaspididae) is almost
worldwide distributed on citrus and in the Mediterranean basin it normally
completes 3 generations per year. It mainly overwinters as virgin female and
immature male on branches of various size. The reproduction is sexual or
parthenogenetic and each female produces an average of 100 eggs with the
parthenogenetic biotypes performing a lower fecundity. This scale insect is
extremely polyphagous and attacks citrus (mainly lemon), acacia, asparagus, carob,
ivy, jojoba, kiwi, mulberry, oleander, olive, palm, peach, pear, plum.
The armour of the female is pale brown in colour, about 1.5–2.5 mm in diameter,
round shaped. The body of the insect is yellowish. The nymphal exuviae are yellow
and located centrally or slightly laterally. The ventral shield is white and very thin.
The pygidium has 3 pairs of lobes, the central ones have a sclerified basal region
while the external ones are poorly developed; dorsal ducts are short and spiracles are
not provided with glands.
Male armour is slightly smaller, white and almost oblong in shape, 1–1.5 mm in
length. The adult male (1 mm in length) has only one pair of wings, like all the other
scales, and is characterized by a long aedeagus. It is yellow in colour with blackishbrown
appendages.
The pest infests branches, leaves and fruits. Heavy attacks may cause loss of
vigour, deformation of infested plant parts, chlorotic spots on leaves and leaf drop.
On the fruits the feeding sites of the scales remain green and do not develop
normally while the rest of the rind changes colour at maturity and grows evenly.
The Oleander scale is controlled by the predatory beetles Chilocorus
bipustulatus, Exochomus quadripustulatus, Rhyzobius lophanthae and Scymnus spp.
(Coleoptera: Coccinellidae). The species is also parasitized by the Hymenoptera
Aphelinidae Aphytis chilensis How., A. chrysomphali, A. diaspidis (How.), A.
hispanicus (Mercet) and Encarsia citrina (Craw).
Regular pruning represents an important tool in controlling this scale as well as
all the other scales. Chemical control can be performed using mineral oils before the
scale moves on the fruits and, in case of heavier infestations, the use of an IGR
(buprofezin) can be considered. The timing of treatments is made harder by the
absence of an efficient monitoring system. Pheromone traps were tried in the field
but they were not commercially developed. A method which proved effective in
monitoring the scale populations, and particularly in placing the chemical
treatments, was based on wrapping sticky tape around 1-year-old branches that have
both old and new wood and are infested by live female scales, in order to capture the
crawlers as they emerge from the females and move across the twigs (Tumminelli,
Perrotta, Raciti, & Colazza, 2006b). The economic threshold varies considerably,