Dialeurodes citri (citrus whitefly)
- Taxonomic Tree
- Notes on Taxonomy and Nomenclature
- Distribution Table
- Risk of Introduction
- Hosts/Species Affected
- Host Plants and Other Plants Affected
- Growth Stages
- List of Symptoms/Signs
- Biology and Ecology
- Natural enemies
- Notes on Natural Enemies
- Detection and Inspection
- Similarities to Other Species/Conditions
- Prevention and Control
- Distribution Maps
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PicturesTop of page
IdentityTop of page
Preferred Scientific Name
- Dialeurodes citri (Ashmead, 1885)
Preferred Common Name
- citrus whitefly
Other Scientific Names
- Aleurodes eugeniae var. aurantii Maskell, 1895
- Aleyrodes (Dialeurodes) citri (Riley & Howard) Cockerell, 1902
- Aleyrodes aurantii (Maskell) Cockerell, 1903
- Aleyrodes citri Ashmead, 1885
- Aleyrodes citri Riley & Howard, 1893
- Aleyrodes kushinasii Sasaki, 1908
- Dialeurodes citri (Ashmead) Quaintance & Baker, 1916
- Dialeurodes citri (Ashmead) var. hederae Takahashi, 1936
- Dialeurodes citri (Ashmead) var. kinyana Takahashi, 1935
- Dialeurodes tuberculatus Takahashi, 1932
International Common Names
- Spanish: mosca blanca del citrico
- French: aleurode des aurantiacees; aleurode du citronnier
Local Common Names
- Germany: Mottenschildlaus, Zitrus-; Weisse Fliege
- Italy: dialeurode degli agrumi
- Japan: mikan-konazorami
- DIALCI (Dialeurodes citri)
Taxonomic TreeTop of page
- Domain: Eukaryota
- Kingdom: Metazoa
- Phylum: Arthropoda
- Subphylum: Uniramia
- Class: Insecta
- Order: Hemiptera
- Suborder: Sternorrhyncha
- Unknown: Aleyrodoidea
- Family: Aleyrodidae
- Genus: Dialeurodes
- Species: Dialeurodes citri
Notes on Taxonomy and NomenclatureTop of page D. citri was originally ascribed to the genus Aleyrodes. Cockerell (1902) used this species as the type of the new subgenus Dialeurodes, which was subsequently elevated to generic rank by Quaintance and Baker (1914). Due to its morphological stability and biological peculiarities, D. citri only has a few synonyms.
DescriptionTop of page Priore (1969) gives a morphological description of all stages of this insect. Patti and Rapisarda (1981), Bink-Moenen and Gerling (1990), and Rapisarda (1990) report detailed information on the fourth-instar nymph (pupal case).
The egg of D. citri is elongated, elliptical, tapered and almost pointed in the anterior part and is posteriorly provided with a stalk. It is creamy-yellow, 0.24-0.27 mm long (without stalk) and 0.09-0.12 mm wide (greater in the distal third).
Nymphal stages are sub-elliptical in shape and almost flattened; they can be easily mistaken for young scale insects, but they have a well-marked vasiform orifice.
First instar: Creamy-yellow, 0.27-0.34 mm long and 0.16-0.21 mm wide. The margin has 14-17 pairs of setae, in addition to the anterior, posterior and caudal ones. The vasiform orifice is almost triangular, and is almost completely covered by the subcordate operculum. The lingula is concealed. Antennae and legs are well developed.
Second instar: Colour and shape similar to the first instar, 0.45-0.55 mm long and 0.30-0.36 mm wide. The margin has only the anterior, posterior and caudal pairs of setae. The vasiform orifice is almost rounded, slightly thickened in its margin and completely covered by the operculum. The antennae and legs are reduced. Tracheal folds are evident.
Third instar: Very similar to the second instar but larger; length 0.62-0.82 mm, width 0.43-0.63 mm.
Fourth instar (pupal case): Colourless or yellowish, oval to broadly oval. Often slightly constricted just posteriorly of thoracic tracheal pores. Body length is 1.00-1.50 mm, and width is 0.60-1.20 mm. The margin is finely crenellated, with well-marked and rounded (10-16 µm in diameter) tracheal pores. The cephalic, eighth abdominal and caudal setae are minute, the first abdominal setae are 'wanting'. Eleven pairs of minute setae are present in a submarginal-subdorsal position. Tubercle clusters are often present on the submedial area, usually on the prothorax, metathorax and the second abdominal segment. The vasiform orifice is relatively small (45-60 µm long), subcircular and with a broad rim, and has toothed posterior and lateral inner margins. The operculum almost fills the vasiform orifice, concealing the tip of the lingula. The ventral region has tracheal folds (both thoracic and abdominal) densely set with microtubercles. According to Benmessaoud-Boukhalfa (1991), slight morphological differences exist between summer and winter pupal cases, mainly pertaining to the dorsal surface and the vasiform orifice. This is the stage used for identification purposes.
The body is creamy-yellow, with white wings that are 0.75-1.10 mm long (hindwings) or 0.95-1.35 mm long (forewings). The compound eyes are well developed, each one divided in two connected parts. The antennae are seven segmented. Forewings have veins reduced to C+Sc, R and a small Cu. The vasiform orifice is almost circular, partly covered by a transverse, subrectangular operculum. The lingula is posteriorly tapered, with an elongated and parallel-sided distal portion.
DistributionTop of page D. citri is believed to be of oriental origin and is probably native to India. It has been widely spread across the world by the activities of man. It has a cosmopolitan distribution in southeastern Asia, the Middle East, the Mediterranean Region, USA, Central and South America. In northern and southern hemispheres, the distribution of D. citri does not cross the line of the 45th parallel. Outside of this zone, infestations by D. citri have been detected only under glass and on imported Citrus material (Bowman and Bartlett, 1978). Moreover, in these situations D. citri can be easily and promptly eradicated.
Distribution TableTop of page
The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.Last updated: 23 Apr 2020
|Continent/Country/Region||Distribution||Last Reported||Origin||First Reported||Invasive||Reference||Notes|
|Algeria||Present||International Institute of Entomology (1996); EPPO (2020)|
|Egypt||Present||Nada (1988); EPPO (2020)|
|Morocco||Present||Mazih (2015); EPPO (2020)|
|Afghanistan||Present||International Institute of Entomology (1996); EPPO (2020)|
|Azerbaijan||Present||International Institute of Entomology (1996); EPPO (2020)|
|Bangladesh||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Fujian||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Guangdong||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Hainan||Present||Zhu WenJing and Fu YueGuan (2013)|
|-Hebei||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Henan||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Hubei||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Hunan||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Jiangsu||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Sichuan||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Zhejiang||Present||International Institute of Entomology (1996); EPPO (2020)|
|Georgia||Present||International Institute of Entomology (1996); EPPO (2020)|
|Hong Kong||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Andhra Pradesh||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Assam||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Bihar||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Delhi||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Himachal Pradesh||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Karnataka||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Kerala||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Madhya Pradesh||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Maharashtra||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Odisha||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Punjab||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Sikkim||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Tamil Nadu||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Uttar Pradesh||Present||International Institute of Entomology (1996); EPPO (2020)|
|-West Bengal||Present||International Institute of Entomology (1996); Konar (1997); EPPO (2020)|
|Israel||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Honshu||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Kyushu||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Shikoku||Present||International Institute of Entomology (1996); EPPO (2020)|
|Lebanon||Present||International Institute of Entomology (1996); EPPO (2020)||First reported: 198*|
|Macau||Present||International Institute of Entomology (1996); EPPO (2020)|
|Pakistan||Present||Mound and Halsey (1978); APPPC (1987); International Institute of Entomology (1996); EPPO (2020)|
|South Korea||Present||International Institute of Entomology (1996); EPPO (2020)|
|Sri Lanka||Present||Mound and Halsey (1978); International Institute of Entomology (1996); EPPO (2020)|
|Taiwan||Present||Mound and Halsey (1978); International Institute of Entomology (1996); EPPO (2020)|
|Tajikistan||Present||International Institute of Entomology (1996); EPPO (2020)|
|Thailand||Present||Mound and Halsey (1978); International Institute of Entomology (1996); EPPO (2020)|
|Turkey||Present||Mound and Halsey (1978); International Institute of Entomology (1996); EPPO (2020)|
|Uzbekistan||Present||International Institute of Entomology (1996); EPPO (2020)|
|Vietnam||Present||International Institute of Entomology (1996); EPPO (2020)|
|Croatia||Present, Localized||EPPO (2020); Šimala et al. (2015)|
|Cyprus||Absent, Unconfirmed presence record(s)||EPPO (2020)|
|France||Present, Localized||International Institute of Entomology (1996); EPPO (2020)|
|-Corsica||Present||International Institute of Entomology (1996); EPPO (2020)|
|Greece||Present||International Institute of Entomology (1996); EPPO (2020)|
|Italy||Present||Mound and Halsey (1978); International Institute of Entomology (1996); EPPO (2020)|
|Malta||Present||International Institute of Entomology (1996); EPPO (2020)|
|Russia||Present, Localized||EPPO (2020)|
|-Southern Russia||Present||EPPO (2020)|
|Slovenia||Present, Localized||EPPO (2020)|
|Spain||Present, Localized||International Institute of Entomology (1996); EPPO (2020)|
|-Canary Islands||Present||Hernández-Suárez et al. (2012); EPPO (2020)|
|United Kingdom||Absent, Intercepted only||Bowman and Bartlett (1978)|
|Bahamas||Present||International Institute of Entomology (1996); EPPO (2020)|
|Bermuda||Present||International Institute of Entomology (1996); EPPO (2020)|
|Costa Rica||Present||CABI (Undated)|
|Cuba||Present||International Institute of Entomology (1996); EPPO (2020)|
|El Salvador||Present||International Institute of Entomology (1996); EPPO (2020)|
|Mexico||Present, Localized||Mound and Halsey (1978); International Institute of Entomology (1996); EPPO (2020)|
|Puerto Rico||Present||International Institute of Entomology (1996); EPPO (2020)|
|United States||Present, Widespread||EPPO (2020)|
|-Alabama||Present||International Institute of Entomology (1996); EPPO (2020)|
|-California||Present||Mound and Halsey (1978); International Institute of Entomology (1996); EPPO (2020)|
|-Colorado||Present||Mound and Halsey (1978); International Institute of Entomology (1996); EPPO (2020)|
|-Florida||Present||Mound and Halsey (1978); International Institute of Entomology (1996); EPPO (2020)|
|-Georgia||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Illinois||Present||Mound and Halsey (1978); International Institute of Entomology (1996); EPPO (2020)|
|-Louisiana||Present||Mound and Halsey (1978); International Institute of Entomology (1996); EPPO (2020)|
|-Mississippi||Present||International Institute of Entomology (1996); EPPO (2020)|
|-North Carolina||Present||Mound and Halsey (1978); International Institute of Entomology (1996); EPPO (2020)|
|-South Carolina||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Texas||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Virginia||Present||International Institute of Entomology (1996); EPPO (2020)|
|-Washington||Present||Mound and Halsey (1978); International Institute of Entomology (1996)|
|Argentina||Present||International Institute of Entomology (1996); EPPO (2020)|
|Brazil||Absent, Unconfirmed presence record(s)||Mound and Halsey (1978); EPPO (2020)|
|Chile||Present||Mound and Halsey (1978); International Institute of Entomology (1996); EPPO (2020)|
|Guyana||Present||International Institute of Entomology (1996); EPPO (2020)|
|Peru||Present||International Institute of Entomology (1996); EPPO (2020)|
Risk of IntroductionTop of page D. citri should be regarded as a quarantine pest in all citrus-growing areas where its occurrence has not yet been detected. Transport of living host-plants or fresh foliage of host-plants presents the main quarantine risk.
Hosts/Species AffectedTop of page D. citri is one of the more polyphagous whiteflies, having been reported on ca 80 plant species, belonging to more than 50 genera and 30 families (Mound and Halsey, 1978). It is an important pest of Citrus, coffee, Diospyros kaki and a number of ornamentals.
Host Plants and Other Plants AffectedTop of page
|Bischofia javanica (bishop wood)||Euphorbiaceae||Other|
|Camellia japonica (camellia)||Theaceae||Other|
|Cephalanthus occidentalis (common buttonbush)||Rubiaceae||Other|
|Choisya ternata (mexican orange-blossom)||Rutaceae||Other|
|Citrus aurantium (sour orange)||Rutaceae||Other|
|Citrus limon (lemon)||Rutaceae||Main|
|Citrus reticulata (mandarin)||Rutaceae||Main|
|Citrus sinensis (navel orange)||Rutaceae||Main|
|Coffea arabica (arabica coffee)||Rubiaceae||Other|
|Diospyros (malabar ebony)||Ebenaceae||Other|
|Diospyros kaki (persimmon)||Ebenaceae||Other|
|Diospyros virginiana (persimmon (common))||Ebenaceae||Other|
|Distylium racemosum (isu)||Hamamelidaceae||Other|
|Ficus benjamina (weeping fig)||Moraceae||Other|
|Ficus macrophylla (moreton Bay fig)||Moraceae||Other|
|Gardenia jasminoides (cape jasmine)||Rubiaceae||Other|
|Hedera helix (ivy)||Araliaceae||Other|
|Lagerstroemia indica (Indian crape myrtle)||Lythraceae||Other|
|Ligustrum (privet)||Oleaceae||Wild host|
|Ligustrum japonicum (Japanese privet)||Oleaceae||Other|
|Lithocarpus (stone oaks)||Fagaceae||Other|
|Lonicera japonica (Japanese honeysuckle)||Caprifoliaceae||Other|
|Maclura pomifera (osage orange)||Moraceae||Other|
|Melia azedarach (Chinaberry)||Meliaceae||Other|
|Myrtus communis (myrtle)||Myrtaceae||Other|
|Nerium oleander (oleander)||Apocynaceae||Other|
|Prunus (stone fruit)||Rosaceae||Other|
|Prunus laurocerasus (cherry laurel)||Other|
|Punica granatum (pomegranate)||Punicaceae||Other|
|Quercus nigra (water oak)||Fagaceae||Other|
|Ricinus communis (castor bean)||Euphorbiaceae||Other|
|Rubus (blackberry, raspberry)||Rosaceae||Other|
|Schefflera (umbrella tree)||Araliaceae||Other|
|Syringa vulgaris (lilac)||Oleaceae||Unknown|
|Syzygium jambos (rose apple)||Myrtaceae||Other|
Growth StagesTop of page Flowering stage, Fruiting stage, Post-harvest, Vegetative growing stage
SymptomsTop of page D. citri almost exclusively colonizes the underside of the leaves of host plants, on which the adults oviposit (without a precise distribution pattern, unlike other citrus-feeding whiteflies) and the young larvae settle, after having inserted their stylets. Infested plants are frequently covered in copious quantities of sticky and transparent honeydew, covering the leaf areas where the whitefly occurs and dropping onto the upper surface of underlying leaves. Sooty mould growth is also abundant. In the case of heavy infestations, the whole canopy of a tree may acquire an almost completely black appearance.
List of Symptoms/SignsTop of page
|Fruit / honeydew or sooty mould|
|Inflorescence / honeydew or sooty mould|
|Leaves / honeydew or sooty mould|
|Stems / honeydew or sooty mould|
Biology and EcologyTop of page D. citri is one of the best-investigated species of whitefly. It is polyvoltine, having several generations per year; in suitable areas, where optimum environmental conditions occur, up to five or six generations are reported yearly. A long winter diapause (spent in the nymphal stage), and a consequently lower number of generations may be observed in nearly all non-native areas, such as the Mediterranean Region. Two generations per year occur in Corsica and Spain (Onillon et al., 1975; Llorens and Capilla, 1994), two to four in Turkey (Soylu, 1980; Ulu, 1985; Uygun et al., 1990), and three in Italy (Priore, 1969; Barbagallo and Patti, 1978). Moreover, the life cycle of D. citri seems to vary according to the host plant. Gargani (1990) noted three yearly generations on privet but only one on persimmon.
Adults of D. citri normally live for ca 10 days, but they can live for as long as 27 days. The female lays her pale yellow eggs scattered singly on the underside of leaves, particularly young ones. The eggs usually hatch in 8-24 days, depending on the season. The young nymphs move around for several hours, then they settle on the leaf underside. Nymphs become sedentary, and their legs become vestigial.
Natural enemiesTop of page
|Natural enemy||Type||Life stages||Specificity||References||Biological control in||Biological control on|
|Aschersonia aleyrodis||Pathogen||Adults/Nymphs||China; Fujian; China; Zhejiang; Cuba; USA; Florida||Citrus|
|Encarsia lahorensis||Parasite||Adults/Nymphs||California; China; Guangdong; Corfu; Florida; France; Greece; Israel; Italy; Italy; Sardinia; Republic of Georgia; Sicily; USA; Alabama; USSR; Uzbekistan; Russia; North Carolina||Citrus; Gardenia jasminoides|
|Serangium parcesetosum||Predator||Adults/Nymphs||Republic of Georgia; USSR||Citrus|
Notes on Natural EnemiesTop of page A large number of natural enemies are known to develop on D. citri, but only a few of them are of relevance to biological control.
The fungal pathogen, Aschersonia is of major importance, especially in areas where the humidity is high. A. aleyrodis is the best known species among this group. In studies carried out in China (Shu-Zheng, 1996), this pathogen was shown to survive, grow and produce spores at 10-32°C (optimum 20-25°C); the temperature for the germination of conidia ranged from 5 to 30°C (optimum 20-30°C). The fungus grew at pH 3-10, although values ranging from 6 to 7 appeared to be optimal for mycelial growth and sporulation. In the field, A. aleyrodis survived 15 months (compared to 17 months at room temperature and 28 months at 0°C under laboratory conditions). Gao et al. (1985) state that this pathogen is highly effective in controlling D. citri in China. When branches infected with spores of the fungus were hung over trees infested by D. citri, the infection rate was 74% 8 months after treatment. A. placenta (which may be conspecific with A. aleyrodis) has been shown to attack nymphs (especially the second and third instars) of D. citri at a rate of 33-78% (Zou, 1988), and has been introduced in the former USSR, where in Adzharia it achieved up to 90% parasitism under favourable conditions (Ponomarenko et al., 1975).
Insect predators of D. citri belong to the Thysanoptera, Heteroptera, Neuroptera and the Coleoptera (including coccinellid beetles of the genera Clitosthethus, Delphastus and Serangium). Clitostethus arcuatus is a predator of D. citri and other similar species (Bemisia tabaci, Siphoninus phillyreae and Trialeurodes vaporariorum). In Italy, C. arcuatus has four generations per year (Loi, 1978; Liotta, 1981). In Sicily, the first generation occurs from mid-April to mid-May, the second in June, the third in July and the fourth from mid- or late-August to the end of September; adults overwinter in cracks in tree bark or in walls, but move into citrus orchards during mild sunny days. Studies carried out in the Republic of Georgia, record C. arcuatus as having only one generation per year (Agekyan, 1977; Loi, 1978). Each C. arcuatus female lays 11-41 eggs on the lower surface of Citrus leaves. Larvae hatch after 3-8 days and pupate after a further 8-24 days, dependent on the temperature. They mainly feed on eggs but also on nymphs of D. citri. Adults emerge 3-8 days after pupation. Another coccinellid species, Serangium parcesetosum, is probably native to India; but it has been introduced in several Citrus-growing areas for the biological control of D. citri, for example in southern France and Corsica (Malausa et al., 1988), during 1986-87, and the former Soviet Union (Timofeeva and Hoang, 1978). On the Black Sea coasts of the Caucasus, S. parcesetosum has four generations per year and destroys up to 90% of whitefly colonies. It passes the winter as adults, which congregate in masses in old leaves and beneath the bark of trees, and resume activity in early April (Timofeeva and Hoang, 1978).
Encarsia lahorensis is regarded as the most efficient parasitoid of D. citri. Its introduction into various citrus-growing areas of the world has resulted in parasitization levels of up to 70-80%. E. lahorensis has been successfully introduced in Greece, Israel, Italy, Republic of Georgia, Turkey and Uzbekistan (Viggiani and Mazzone, 1978; Pappas and Viggiani, 1979; Argov, 1988, Basova, 1991; Yoldas and Oncuer, 1992). In Florida, USA, E. lahorensis has become well-established in 59 of 67 counties (Sailer et al., 1984). In Alabama, USA, populations of D. citri were drastically reduced one year after the introduction of E. lahorensis, and 3 years after its release, D. citri was no longer a pest in areas where E. lahorensis was present (Hudson and Williams, 1986). Females of E. lahorensis develop as primary endoparasites of D. citri, but the males (which hatch from unfertilized eggs) develop ectoparasitically on female parasite larvae or conspecific pupae within the host; occasionally they may develop on the larvae or pupae of other males, when superparasitism occurs (Viggiani and Mazzone, 1978). Larvae that had almost completed their development and young pupae of both sexes of D. citri appear to be the stages preferred by ovipositing E. lahorensis. E. lahorensis has 4-6 generations per year in southern Italy (Viggianni and Mazzone, 1978), taking 17-25 days to develop from egg to adult.
ImpactTop of page D. citri is one of the most important pests of Citrus spp., to which it may cause serious damage, through the extraction of large quantities of sap and the development of unsightly sooty mould on the abundant excreted honeydew. Direct interventions are usually required against D. citri in newly colonized areas, where natural enemies are scarce, and in citrus groves where pesticide treatments, mostly directed at other pests, have broken the natural balance.
DiagnosisTop of page A slide-mounted preparation of the pupal case (made according to the procedures of Martin, 1987) should be examined microscopically at a high magnification to confirm diagnosis. Martin (1987) provides a key.
Detection and InspectionTop of page The leaves of potential host plants (especially their underside) should be inspected for D. citri. Colonies are likely to contain small white winged adults, as well as eggs and nymphs.
Similarities to Other Species/ConditionsTop of page D. citri resembles D. kirkaldyi, with which it has several host plants in common (including Citrus and Jasminum spp.). D. citri differs from D. kirkaldyi by the absence, in the pupa, of the first abdominal setae and in the position of the eighth abdominal setae. A median brown patch usually occurs in D. kirkaldyi (Bink-Moenen and Gerling, 1990). D. citrifolii also occurs on Citrus in the Neotropical region, southern USA, Western Samoa, India and the Far-East of Asia. D. citrifolii clearly differs from D. citri by not having stippled tracheal folds, and by possessing thoracic tracheal pores each with 3-5 internal teeth (Martin, 1987).
Prevention and ControlTop of page
Due to the variable regulations around (de)registration of pesticides, your national list of registered pesticides or relevant authority should be consulted to determine which products are legally allowed for use in your country when considering chemical control. Pesticides should always be used in a lawful manner, consistent with the product's label.IPM Programmes
Control of D. citri infestations should always be arranged according to the general criteria of integrated control; thus chemical and biological methods should be opportunely balanced to obtain a synergistic effect. Thresholds for the application of an artificial control are generally considered within the European Union as the occurrence of 20-30 whitefly nymphs per leaf on orange and lemon, and of 5-10 whitefly nymphs per leaf on mandarin or mandarin-like citrus species.
In areas where D. citri is a recent introduction, releases of the parasitoid Encarsia lahorensis are often beneficial. Introductions may be achieved using either the 'bouquets' or the 'small plants' methods: the former appears to be more practical for small-scale releases in private orchards, whilst the second is more useful in large-scale releases in large citrus growing areas (see Natural Enemies). Spring and autumn appear to be the best seasons for introducing E. lahorensis.
Chemical applications usually provide only a temporary suppression of D. citri, which is often followed by resurgence. Thus, chemical control should be considered only for heavy infestations, when it is necessary to quickly reduce the whitefly population before trying to rebuild the balance with the re-introduction of natural enemies. Simple sprayed oils or oil emulsions are generally employed which contain 1% oil in the spray mixture (Priore and Pandolfo, 1972; Barbagallo and Patti, 1978; Ulu, 1987; Uygun et al., 1990). Particular attention should be given to carefully treating the underside of leaves, since the greatest number of nymphs is found there. Trials have been conducted in Israel for the use of the insect growth regulators, buprofezin and pyriproxyfen. The former proved to be more effective on first- and second- instar nymphs, whilst the latter exhibited more ovicidal properties. They were both reported not to adversely affect E. lahorensis (Peleg, 1990).
ReferencesTop of page
APPPC, 1987. Insect pests of economic significance affecting major crops of the countries in Asia and the Pacific region. Technical Document No. 135. Bangkok, Thailand: Regional Office for Asia and the Pacific region (RAPA).
Argov Y, 1988. Biological control of the citrus whitefly, Dialeurodes citri (Ashmead) (Homoptera: Aleyrodidae). Proceedings of the VI International Citrus Congress, Tel Aviv, Israel, 3:1169-1175.
Barbagallo S; Patti I, 1978. Note biologiche ed orientamenti di lotta contro Dialeurodes citri (Ashm.) in Sicilia orientale. Atti Giornate Fitopatologiche, 1:237-244.
Benmessaoud-Boukhalfa H, 1991. Morphology of the 4th-stage larvae (winter larvae and summer larvae) of Dialeurodes citri Ash. (Homoptera - Aleyrodidae) by scanning electron microscopy. Mededelingen van de Faculteit Landbouwwetenschappen, Rijksuniversiteit Gent, 56(3b):1065-1073.
Cockerell TDA, 1902. The classification of the Aleyrodidae. Proc. Acad. Nat. Sci. Philad, 54:279-283.
EPPO, 2014. PQR database. Paris, France: European and Mediterranean Plant Protection Organization. http://www.eppo.int/DATABASES/pqr/pqr.htm
Gao RX; Ouyang Z; Gao ZX; Zheng JX, 1985. A preliminary report on citrus white fly control with Aschersonia aleyrodis. Journal of Fujian Agricultural College (Fujian Nongxueyuan Xuebao), 14(2):127-133.
Hernández-Suárez E; Martin JH; Gill RJ; Bedford ID; Malumphy CP; Reyes Betancort JA; Carnero A, 2012. The aleyrodidae (Hemiptera: Sternorrhyncha) of the Canary Islands with special reference to Aleyrodes, Siphoninus, and the challenges of puparial morphology in Bemisia. Zootaxa, 3212:1-76. http://www.mapress.com/zootaxa/2012/f/zt03212p076.pdf
Hudson WG; Williams ML, 1986. Release of the parasitic wasp, Encarsia lahorensis (Hymenoptera: Aphelinidae), for control of citrus whitefly (Homoptera: Aleyrodidae) on gardenia in Alabama. Environmental Entomology, 15(3):585-589.
Loi G, 1978. Ecological and behavioural observations on Clitostethus arcuatus (Rossi) (Coleoptera Coccinellidae Scymninp), a predator of Dialeurodes citri (Ashm.) in Tuscany. Frustula Entomologica, 1:123-145.
Malausa JC; Franco E; Brun P, 1988. Establishment on the Cote d'Azur and in Corsica of Serangium parcesetosum (Col.: Coccinellidae), a predator of the citrus whitefly, Dialeurodes citri (Hom.: Aleyrodidae). Entomophaga, 33(4):517-519.
Mazih A, 2015. Status of citrus IPM in the southern Mediterranean basin Morocco, North Africa. Acta Horticulturae [XII International Citrus Congress - International Society of Citriculture, Valencia, Spain.], No.1065:1097-1103. http://www.actahort.org/books/1065/1065_138.htm
Ministerio de Agricultura y Ganadería Servicio Fitosanitario del Estado (Costa Rica), 2009. Listado de Plagas (insectos y ácaros) en cultivos de importancia económica en Costa Rica (C). http://www.protecnet.go.cr/laboratorios/plagcul/cultivoc.htm
Nada SMA, 1988. Three species of Aleyrodidae new to Egypt (Aleyrodidae: Homoptera). Bull. Soc. Ent. Egypte, 68:55-59.
Onillon JC; Onillon J; Brun P, 1975. Contribution to the study of the population dynamics of Homoptera infesting Citrus. II. 3. Preliminary observations on the comparative development of populations of Dialeurodes citri Ashmead (Homopt. Aleurodidae) in Corsica and the south-east of France. Bulletin SROP [Section Regionale Ouest Palearctique], 5:167-172.
Pappas S; Viggiani G, 1979. Prospaltella lahorensis How. (Hym. Aphelinidae), a parasite of Dialeurodes citri (Ashm.) (Hom. Aleyrodidae) introduced into Corfu. Bollettino del Laboratorio di Entomologia Agraria "Filippo Silvestri", Portici, 36:38-41.
Priore R, 1969. Il Dialeurodes citri (Ashmead) (Homoptera: Aleyrodidae) in Campania. Boll. Lab. Ent. Agr. Filippo Silvestri, 27:287-316.
Priore R; Pandolfo FM, 1972. Chemical control tests against Dialeurodes citri (Ashm.) (Homoptera: Aleyrodidae) in Campania in the years 1971-72. Bollettino del Laboratorio di Entomologia Agraria 'Filippo Silvestri' Portici, 30:139-144.
Quaintance AL; Baker AC, 1914. Classification of the Aleyrodidae. Part II. Tech. Ser. Bur. Ent. U.S, 27:95-109.
Rapisarda C, 1990. Gli Aleirodi degli agrumi in Italia. Phytophaga, Palermo, 3(1985-89):173-198.
Sailer RI; Brown RE; Munir B; Nickerson JCE, 1984. Dissemination of the citrus whitefly (Homoptera: Aleyrodidae) parasite Encarsia lahorensis (Howard) (Hymenoptera: Aphelinidae) and its effectiveness as a control agent in Florida. Bulletin of the Entomological Society of America, 30(2):36-39.
Simala M; Milek TM; Pintar M, 2015. Alien whiteflies (Hemiptera: Aleyrodidae) of Europe recorded in Croatia [Conference poster]. In: Zbornik predavanj in referatov 12. Slovenskega posvetovanja o varstvu rastlin z mednarodno udelezbo, 3.-4. marec 2015, Ptuj, Slovenija [ed. by Trdan, S.]. Ljubljana, Slovenia: Drustvo za Varstvo Rastlin Slovenije, 267-271.
Soylu OZ, 1980. Investigations on the biology and control of citrus whitefly (Dialeurodes citri Ashmead) injurious in citrus orchards in the Mediterranean region of Turkey. Bitki Koruma Bulteni, 20(1/4):36-53.
Timofeeva TV; Hoang Duik Nyuan, 1978. Morphological and biological characteristics of the Indian coccinellid Serangium parcesetosum Sicard (Coleoptera, Coccinellidae) - a predator of the citrus whitefly in Adzharia. Entomologicheskoe Obozrenie, 57(2):302-308.
Ulu O, 1985. Investigations of the taxonomic characters, damage, biology, ecology and control of the citrus whitefly Dialeurodes citri (Ashmead) (Homoptera: Aleyrodidae), which attacks citrus in the pgean region. Ege Universitesi Ziraat Fakultesi Dergisi, 22(3):159-174.
Ulu O, 1987. Correlation between the mortality caused by exposure to white summer oil sprays in pupae of citrus whitefly (Dialeurodes citri (Ash.) (Homoptera: Aleyrodidae)) and time and temperature. Turkiye I. Entomoloji Kongresi Bildirileri, 13-16 Ekim 1987, Ege Universitesi, Bornova, Izmir Bornova/Izmir, Turkey; Ege Universitesi Ataturk Kultur Merkezi, 317-324.
Uygun N; Ohnesorge B; Ulusoy R, 1990. Two species of whiteflies on citrus in eastern Mediterranean: Parabemisia myricae (Kuwana) and Dialeurodes citri (Ashmead). Morphology, biology, host plants and control in southern Turkey. Journal of Applied Entomology, 110(4):471-482.
Viggiani G; Mazzone P, 1978. Morphology, biology and utilisation of Prospaltella lahorensis How. (Hym. Aphelinidae), an exotic parasite introduced into Italy for the biological control of Dialeurodes citri (Ashm.). Bollettino del Laboratorio di Entomologia Agraria 'Filippo Silvestri', Portici, 35:99-160.
Yoldas Z; Oncuer C, 1992. An investigation on the colonization of Encarsia lahorensis (How.) an introduced parasitoid of the citrus whitefly, Dialeurodes citri (Ashm.) in Izmir. Proceedings of the Second Turkish National Congress of Entomology Izmir, Turkey: Ege Universitesi, 79-87.
APPPC, 1987. Insect pests of economic significance affecting major crops of the countries in Asia and the Pacific region. In: Technical Document No. 135, Bangkok, Thailand: Regional Office for Asia and the Pacific region (RAPA).
Bowman C E, Bartlett P W, 1978. Dialeurodes citri (Ashmead) and D. citrifolii (Morgan) (Hemiptera: Aleyrodidae) infesting imported Citrus under glass in Britain. Plant Pathology. 27 (4), 203. DOI:10.1111/j.1365-3059.1978.tb01119.x
CABI, Undated. CABI Compendium: Status as determined by CABI editor. Wallingford, UK: CABI
Hernández-Suárez E, Martin J H, Gill R J, Bedford I D, Malumphy C P, Reyes Betancort J A, Carnero A, 2012. The aleyrodidae (Hemiptera: Sternorrhyncha) of the Canary Islands with special reference to Aleyrodes, Siphoninus, and the challenges of puparial morphology in Bemisia. Zootaxa. 1-76. http://www.mapress.com/zootaxa/2012/f/zt03212p076.pdf
Šimala M, Milek T M, Pintar M, 2015. Alien whiteflies (Hemiptera: Aleyrodidae) of Europe recorded in Croatia [Conference poster]. In: Zbornik predavanj in referatov 12. Slovenskega posvetovanja o varstvu rastlin z mednarodno udeležbo, 3.-4. marec 2015, Ptuj, Slovenija [Zbornik predavanj in referatov 12. Slovenskega posvetovanja o varstvu rastlin z mednarodno udeležbo, 3.-4. marec 2015, Ptuj, Slovenija.], [ed. by Trdan S]. Ljubljana, Slovenia: Društvo za Varstvo Rastlin Slovenije. 267-271.
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