Eriosoma lanigerum (woolly aphid)
- 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
- Eriosoma lanigerum (Hausmann, 1802)
Preferred Common Name
- woolly aphid
Other Scientific Names
- Aphis lanigera (Hausmann, 1802)
- Aphis lanigerum Hausmann, 1802
- Coccus mali Bingley, 1803
- Eriosoma lanata (Salisbury, 1816)
- Eriosoma mali Leach, 1818
- Mimaphidus lanata (Salisbury, 1816)
- Mimaphidus lanigerum (Hausmann, 1802)
- Mimaphidus mali ((Leach, 1818)
- Myzoxyles lanigerum (Hausmann, 1802)
- Myzoxyles mali (Leach, 1918)
- Myzoxylos lanata (Salisbury, 1816)
- Myzoxylus laniger
- Myzoxylus lanigerus (Hausmann, 1802)
- Myzoxylus mali Blot, 1831
- Schizoneura lanigera Gillette, 1908
International Common Names
- English: American blight; aphid, elm rosette; aphid, woolly apple; apple root aphid; blight, American; elm rosette aphid; woolly apple aphid
- Spanish: afido de sangre; pulgón lanigero; pulgón lanigero del manzano
- French: puceron lanigère; puceron lanigère du pommier
- Portuguese: pulgao lanigero (Brazil); pulgao lanigero da macieira (Brazil)
Local Common Names
- Brazil: pulgao lanigero; pulgao lanigero da macieira
- Denmark: blodlus
- Finland: verikirva
- Germany: Blutlaus, Wollige Apfel-; Wollige Apfelblutlaus
- Israel: knimat hadam
- Italy: Afide lanigero del melo; Pidocchio rosso del melo; Pidocchio sanguigno
- Japan: Ringo-watamusi
- Netherlands: Appelbloedluis; Bloedluis, wollige
- Norway: blodlus
- Sweden: blodlus
- Turkey: elma kabuklu biti
- ERISLA (Eriosoma lanigerum)
Taxonomic TreeTop of page
- Domain: Eukaryota
- Kingdom: Metazoa
- Phylum: Arthropoda
- Subphylum: Uniramia
- Class: Insecta
- Order: Hemiptera
- Suborder: Sternorrhyncha
- Unknown: Aphidoidea
- Family: Aphididae
- Genus: Eriosoma
- Species: Eriosoma lanigerum
Notes on Taxonomy and NomenclatureTop of page E. lanigerum (Hausmann) is one of 20 species in the genus Eriosoma, in the tribe Eriosomatini of the subfamily Pemphiginae (Blackman and Eastop, 1994). The diploid chromosome number is 2n = 12, although male sexuales are apparently 2n = 11 (Gautam and Verma, 1983a).
DescriptionTop of page Relatively small to medium-sized aphids, characterized by a reddish-brown body, a blood-red stain when crushed and a fluffy, flocculent wax covering (Palmer, 1952; Blackman and Eastop, 1984). Specialized dermal glands produce the characteristic fluffy or powdery wax, which gives E. lanigerum its characteristic 'woolly' appearance.
Hibernating apterous virginoparae occurring on roots of apple over winter are very dark dusky green. They appear nearly black, especially on the head and thorax, although sometimes a dingy yellowish-brown, and lack the white waxy covering of other virginoparae. Appendages and the distal end of the rostrum are dusky brown (Palmer, 1952).
Apterous summer virginoparae are 1.2-2.6 mm in length, purple, red or brown and covered with a thick white flocculent wax. Antennae are dusky brown; tibiae yellowish to slightly dusky brown. They have a relatively small cornical pore size (0.06-0.07 mm). Apterae body length 1.2-2.6 mm (Palmer, 1952; Blackman and Eastop, 1984).
Alate virginoparae are 1.8-2.3 mm long and have a reddish-brown abdomen with a covering of woolly white wax posteriorly. There are two or three sensoria on antennal segment VI. They have a relatively small cornical pore size (around 0.05 mm) (Blackman and Eastop, 1984).
Oviparae are apterous, and rusty yellow to rusty brown. Males are apterous, and yellowish to dusky brown to dark green (Palmer, 1952).
DistributionTop of page E. lanigerum probably originated in eastern North America, but it now has a worldwide distribution (CIE, 1975), having been distributed mainly via apple rootstocks.
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.
Risk of IntroductionTop of page E. lanigerum is considered to be a phytosanitary risk in many regions, due to its root-dwelling habitat and its possible presence on imported apple rootstocks. It is listed in the EPPO A2 quarantine list (EPPO, 1979). For example, in Norway, where the aphid is not established, E. lanigerum is considered to be of significant quarantine importance (Edland, 1990).
Hosts/Species AffectedTop of page E. lanigerum is found on apple (Malus spp.), on which it can be a severe pest, and occasionally on certain other woody host plants in the family Rosaceae. It is restricted to apple in some areas where it has been introduced, for example, parts of Australia (Asante, 1994). It is elsewhere found on species of Crataegus, Sorbus and Cotoneaster, and also rarely on pear and species of Cydonia (Blackman and Eastop, 1984).
Host Plants and Other Plants AffectedTop of page
|Crataegus spp.||Rosaceae||Wild host|
|Cydonia oblonga (quince)||Rosaceae||Wild host|
|Malus (ornamental species apple)||Rosaceae||Main|
|Malus domestica (apple)||Rosaceae||Main|
|Malus sylvestris (crab-apple tree)||Rosaceae||Wild host|
|Prunus domestica (plum)||Rosaceae||Wild host|
|Pyracantha (Firethorn)||Rosaceae||Wild host|
|Pyrus communis (European pear)||Rosaceae||Other|
|Sorbus americana (American mountainash)||Rosaceae||Wild host|
|Sorbus spp.||Rosaceae||Wild host|
Growth StagesTop of page Flowering stage, Fruiting stage, Vegetative growing stage
SymptomsTop of page E. lanigerum occurs on the both the aerial and subterranean woody tissue of apple. It does not feed on the leaves. Aphid colonies on the trunk, branches or twigs can cause deformations, blisters, splitting and cancer-like swellings of the bark (Blackman and Eastop, 1984). Compounds in aphid saliva that are toxic to trees are partly responsible for the severity of this damage. Galling of aerial plant parts can reach the size of a walnut and interfere with sap circulation.
Root infestations also cause galling. Damage to roots encourages secondary infection, particularly the formation of root canker, a disease caused by basidiomycete fungi (Molinari, 1986). In growth chamber experiments, stem splitting and root galling formed as a result of E. lanigerum feeding, 4 and 8 weeks after initial infection, respectively. Feeding resulted in greater shoot and root dry weights and a disruption in nutrient balance, with reduced foliar nitrogen and phosphorous compared to control trees (Weber and Brown, 1988).
List of Symptoms/SignsTop of page
|Fruit / honeydew or sooty mould|
|Roots / galls along length|
|Roots / galls at junction with stem|
|Roots / swollen roots|
|Stems / canker on woody stem|
|Stems / external feeding|
|Stems / galls|
|Stems / honeydew or sooty mould|
Biology and EcologyTop of page E. lanigerum is anholocyclic on apple worldwide, reproducing year-round without host-alternation. Colonies persist on hosts during the winter by living on the plant roots or within bark crevices. Although anholocyclic, an abortive sexual phase occurs in many parts of the world, with sexuales and eggs being produced on apple, but the eggs of this species are not viable and do not hatch (Blackman and Eastop, 1984).
Apterous and alate virginoparae, and sexuales (males and oviparae), appear at particular times during the life cycle on apple. In the USA, overwintering populations start to breed during March to April. Each female can produce over 100 nymphs. Up to 10-12 generations a year can occur in the USA and Europe (for example, France and Italy), from spring to autumn (Molinari, 1986), although in Michigan, USA, and other more northerly parts of North America and Europe, three to four generations may be more usual.
In Australia, Asante (1994) found that alates appearing in early November produced only virginoparae, alates appearing from late November to late January produced a mixture of virginoparae and sexuales, whereas those appearing from February to April produced exclusively sexuales. The sexuales were apterous, had degenerate mouthparts and produced non-viable eggs. The perpetuation of the species appeared to be entirely due to parthenogenesis, with overwintering accomplished in the form of cold-resistant apterous virginoparae.
In India, Gautam and Verma (1983b) observed apterous virginoparae undergoing four moults resulting in five instars. The pre-reproductive and reproductive stages were longer in winter than in summer, whereas fecundity was greater in summer than in winter.
First-instar nymphs are highly mobile and will disperse from crowded populations to establish new colonies (Hoyt and Madsen, 1960) and move between the roots and shoots throughout the year. However, a distinct seasonal migration occurs, from aerial parts to the roots and back, with a pronounced movement of first-instar nymphs at these times (Hoyt and Madsen, 1960). Annual upward and downward movement peaks were recorded in India, for example, during mid-June and October to November, in response to changes in ambient and soil temperatures (Sushma Bhardwaj and Chander, 1995). Differential mortality of aphids on the exposed shoots and sheltered roots also contributes to the seasonal shift in habitat on host plants.
On aerial plant parts, the preference for sheltered sites, including wounds and axil buds, is possibly an adaptation to avoid natural enemies (Brown and Schmitt, 1994).
Natural enemiesTop of page
|Natural enemy||Type||Life stages||Specificity||References||Biological control in||Biological control on|
|Aphelinus mali||Predator/parasite||Nymphs||Argentina; Australia; Belgium; Brazil; Chile; Colombia; Costa Rica; Cyprus; Denmark; Ecuador; Egypt; France; Germany; Himachal Pradesh; India; Iraq; Israel; Italy; Japan; Kenya; Malta; Mexico; Netherlands; New Zealand; Pakistan; Peru; Poland; Portugal; Russian Far East; Saudi Arabia; South Africa; Spain; Sweden; Switzerland; Tasmania; UK; Uruguay; USSR; Venezuela; Western Australia; Zimbabwe||apples|
|Brinckochrysa scelestes||Predator||Adults/Nymphs||Himachal Pradesh|
|Eupeodes confrater||Predator||Adults/Nymphs||India; India; Himachal Pradesh||apples|
|Exochomus melanocephalus||Predator||Adults/Nymphs||Ascension; Australia||apples|
|Hippodamia convergens||Predator||Adults/Nymphs||South Africa||apples|
Notes on Natural EnemiesTop of page Data for natural enemies of E. lanigerum worldwide were summarized by Asante (1997), who reported that aphid colonies were attacked by five species of hymenopterous endoparasitoids and two species of Acarina (ectoparasites). In addition, 73 species of predatory insects belonging to five orders and seven families (Coccinellidae, Chrysopidae, Hemerobiidae, Forficulidae, Lygaeidae, Syrphidae and Cecidomyiidae) have been reported to feed on E. lanigerum. Verticillium lecanii is the only fungal pathogen known to infect E. lanigerum (Asante, 1997).
E. lanigerum is the preferred host of Aphelinus mali, the only important host-specific natural enemy. This parasitoid, which originates from the USA, is now widespread and has been introduced into many apple-growing regions as a biological control agent. The hyperparasitoids Asaphes vulgaris, A. suspensus, Pachyneuron solitarium and Aphidencyrtus aphidivorus are often associated with A. mali (von Kogler, 1989).
Predation of E. lanigerum by the earwig Forficula auricularia was studied by Mueller et al. (1988). Exclusion and feeding experiments performed in Poland showed that Exochomus quadripustulatus played an important role in controlling E. lanigerum during early spring, whereas during the summer F. auricularia and sometimes Coccinella septempunctata were important (Mols, 1996).
ImpactTop of page E. lanigerum is an important economic pest of apple, causing severe damage through direct feeding, but not as a vector of apple viruses (Blackman and Eastop, 1984). It infests both the canopy and root system of apple trees, although root damage is usually more severe than stem damage. Root damage is also harder to detect and more difficult to control. It is a common and highly injurious apple pest in the USA, particularly in areas of Maryland and Virginia (Weber and Brown, 1988). Thakur and Dogra (1980) cited E. lanigerum as the most important pest of apple in India. It is also a significant apple pest in Europe, the Middle East, the Far East, South America, Australia and New Zealand.
Yield losses due to infestation of apple tree roots were studied in West Virginia, USA, by Brown et al. (1995). In a year of high fruit production, there was a significant reduction in the number of fruit and weight of fruit per tree, partly because of increased fruit drop and reduced fruit set. Average yield losses were 2.4 kg (13 apples) per tree, representing a gross loss of $465.18/ha. Aphids were observed on only 11.5% of terminal branches, suggesting that a reduction in the amount of storage carbohydrates in galled roots may be a partial explanation of how the pest reduces tree growth and production.
Brown et al. (1991) found that root galls caused by E. lanigerum were characterized by a proliferation of anomalous non-functional xylem. Disruption of root xylem, resulting in resistance to water conduction, is one mechanism by which E. lanigerum reduces the growth of apple trees. Heavy infestations may result in the formation of swellings and wounds that permit the entry of the fungi Nectria ditissima and N. galligena, which produce cankers (Molinari, 1986). Heavily infested trees lack vigour, due to disturbances in nutrient balance, but it is usually difficult to separate the various direct and indirect effects of aphid feeding.
Fruit can be directly affected, through the deposition of honeydew from colonies feeding on adjacent branches or twigs. These can cause cosmetic damage and lead to the growth of sooty moulds on the apples. Weber and Brown (1988) reported that aphids can sometimes infest the cores of some cultivars.
Damage is particularly severe in young trees. Roots of nursery trees, for example, can be particularly affected. Mature trees are often little affected, even though levels of infestation are generally greatest in orchards over 25 years old (Molinari, 1986).
Detection and InspectionTop of page E. lanigerum is found on the stems and roots of apple. Inspect for aphid presence on aerial plant parts by looking for whitish colonies on branches, especially around healing pruning cuts or wounds in the bark, throughout mid- to late-summer. Microhabitat preferences of arboreal colonies during the spring is for wound and other protected feeding sites on the tree branches and trunk, whereas leaf axils were the predominant microhabitat (51% of the colonies observed) from the end of May to August (Brown and Schmitt, 1994).
In Massachusetts, USA, standard inspection involves examining five prunings per tree, on one tree per 3.5 acres, whereas a provisional threshold for treatment is 50% of pruning cuts infected. Aphids generally show a preference for the lower part of the canopy and the trunk. At low infestations, E. lanigerum is confined to the trunk and large branches, but disperses to establish colonies on twigs or new lateral growths during peak populations (Asante et al., 1993).
Similarities to Other Species/ConditionsTop of page In North America, E. lanigerum was once thought to overwinter on elm (Ulmus spp.) and utilize apple as a secondary host plant. However, E. lanigerum is now considered to be a separate species from closely related species that live on elm. Previous records of E. lanigerum on elm are most likely to have been E. herioti, which induces rosette galls on species of Ulmus and migrates from Ulmus americana to the roots of species of Crataegus, apple and Sorbus americana (Blackman and Eastop, 1984, 1994). Records describing E. lanigerum on U. americana may also be misidentifications of E. crataegi or the woolly elm aphid, E. americanum (CIE, 1975).
Prevention and ControlTop of page
The chalcidoid parasite Aphelinus mali has been introduced into many countries in attempts to control E. lanigerum. It was originally native to the USA, but has become acclimatized in Europe and has now been introduced into apple-growing regions worldwide. Where aboveground infestations dominate, control of E. lanigerum has been very successful, but where root-feeding populations are important, the results have been less good. A review of the history and results of biological control of this pest is provided by Clausen (1978).
In laboratory studies performed by Mueller et al. (1992), A. mali parasitized all stages of E. lanigerum, but preferred third-instar nymphs, whereas rates of parasitism were inversely proportional to host colony size, with small colonies and long, thin colonies having a greater proportion of individuals parasitized.
A. mali was first introduced into India during the 1930s, and 98% control was soon achieved in the Kullu Valley, Himachal Pradesh (Thakur and Dogra, 1980).
In field studies undertaken in New Zealand, Shaw et al. (1996) reported that parasitism of E. lanigerum by A. mali exceeded 80% by late April, and control was achieved without the need for specific aphicide sprays. High levels of parasitism by A. mali (80%) were also recorded at low population densities of E. lanigerum in Mexico (Tejada and Rumayor, 1986), whereas parasitism rates of over 50% were recorded during the summer in West Virginia, USA (Brown and Schmitt, 1994). E. lanigerum was controlled by A. mali in pesticide-free apple orchards in Israel (Oppenheim et al., 1997).
In the Netherlands, the predatory coccinellid Exochomus quadripustulatus is the most common and most widespread coccinellid in apple orchards, and contributes to aphid control alongside A. mali in the spring (Bogya, 1996). In India, releases of A. mali have been accompanied by releases of the predators Brinckochrysa scelestes and Eupeodes confrater as a biological control for E. lanigerum (Thakur and Dogra, 1980; Thakur et al., 1992). In Europe, the earwig Forficula auricularia could be an important supplementary biological control agent against E. lanigerum (Mueller et al., 1988). Predators are not effective against subterranean aphid populations.
The use of entomopathogenic nematodes to control root-dwelling populations of E. lanigerum was described by Brown et al. (1992).
One method of preventing the development of reservoir populations of E. lanigerum underground is to use rootstocks of resistant cultivars. Apple cultivars with some degree of reported resistance include Northern Spry (Cummins et al., 1981) and Golden Delicious (Sachan and Gangwar, 1987). However, most interest has centred on the Malling Merton (MM) series of rootstocks, which are derived from Northern Spry. These rootstocks are not totally resistant to E. lanigerum, but infestation levels are significantly and consistently lower than on other rootstocks, and they have been widely used in pest control programmes.
Thirty cultivars and breeding lines of eight Malus species were tested for resistance to E. lanigerum in a Chinese study (Deng et al., 1993), in which a line of Malus baccata (Jin 67) was selected as stock for future breeding. It exhibited less root damage due to E. lanigerum, was winter hardy and induced dwarfism in apple crosses.
Recommended chemical treatments against E. lanigerum on the aerial parts of trees usually consist of yellow mineral oil, applied in the winter against hibernating immature forms of the aphid and other apple pests. This is followed by sprays of systemic products such as chlorpyrifos or demeton-methyl during the growing period of the tree, but especially after flowering, when predators are less abundant (Molinari, 1986).
Chlorpyrifos also gives good control, but is highly toxic to Aphelinus mali, the most important parasitoid of E. lanigerum. Pirimicarb gives reasonable aphid control without adversely affecting A. mali, although it lacks persistence and is not efficient in killing colonies hidden in cankers or pruning wounds (Staubli and Chapuis, 1989).
In nurseries, root dips of fenitrothion can provide effective control. Subterranean populations in orchards can be treated with granules of dimethoate. Banding of trunks with granules of these insecticides has also been useful in decreasing infestations, by checking the movement of first-instar nymphs that migrate between aerial and subterranean habitats on apple (Thakur and Dogra, 1980).
The reduced use of broad-spectrum pesticides, enhanced diversity of arboreal predators and parasitoids, and high populations of key natural enemies, particularly the parasitoid A. mali, are key features of IPM in apple against E. lanigerum. IPM programmes have been described in Australia (Thwaite, 1997), New Zealand (Shaw et al., 1996), Romania (Baicu et al., 1997) and South Africa (Nel and Addison, 1993).
Air-blast sprayer applications of mineral oil, or oil plus buprofezin are applied in apple orchards under IPM programmes in New Zealand. The natural enemy A. mali can then control E. lanigerum populations under these spray regimes (Shaw et al., 1996).
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).
Asante SK, 1994. Seasonal occurrence, development and reproductive biology of the different morphs of Eriosoma lanigerum (Hausmann) (Hemiptera: Aphididae) in northern Tablelands of New South Wales. Journal of the Australian Entomological Society, 33(4):337-344
Asante SK, 1997. Natural enemies of the woolly apple aphid, Eriosoma lanigerum (Hausmann) (Hemiptera: Aphididae): a review of the world literature. Plant Protection Quarterly, 12(4):166-172; 3 pp. of ref.
Bogya S, 1996. The role of conifer ladybird (Exochomus quadripustulatus L.) in controlling the populations of woolly apple aphid (Eriosoma lanigerum Hausm.). No^umlaut~ve^acute~nyve^acute~delem, 32(8):407-410; 4 ref.
Boldyreva EP, 1970. The ecology of Aphelinus mali Hal. (Hymenoptera, Aphelinidae) - a parasite of the woolly apple aphid in Tadzhikistan. Entomologicheskoe Obozrenie, 49(4):744-748.
Brown MW; Jaeger JJ; Pye AE; Schmitt JJ, 1992. Control of edaphic populations of woolly apple aphid using entomopathogenic nematodes and a systemic aphicide. Journal of Entomological Science, 27(3):224-232
Clausen CP, 1978. Introduced Parasites and Predators of Arthropod Pests and Weeds: a World Review. Agricultural Handbook No. 480. Washington DC, USA: Agricultural Research Service, United States Department of Agriculture.
Cummins JN; Forsline PL; Mackenzie JD, 1981. Woolly apple aphid colonization on Malus cultivars. Journal of the American Society for Horticultural Science, 106(1):26-30.
Deng JiaQi; Rui GuangSheng; Guan YuTian; Yu YingQun; Zhang DongMin; Hong JianYuan, 1993. The selection of an apple stock line, Siberian crabapple Jin 67, immune to the woolly apple aphid. Acta Phytophylacica Sinica, 20(3):217-222; 6 ref.
European and Mediterranean Plant Protection Organization, 1979. Data sheets on quarantime organisms. EPPO list A2. Data sheets on quarantime organisms. EPPO list A2. European and Mediterranean Plant Protection Organization. Paris France,
Gontijo LM; Cockfield SD; Beers EH, 2012. Natural enemies of woolly apple aphid (Hemiptera: Aphididae) in Washington State. Environmental Entomology, 41(6):1364-1371. http://esa.publisher.ingentaconnect.com/content/esa/envent/2012/00000041/00000006/art00008
Hoyt SC; Madsen HF, 1960. Dispersal behaviour of the first instar nymphs of the woolly apple aphid. Hilgardia, 30:267-299.
Kogler T von, 1989. The parasitoids of the woolly apple aphid (Eriosoma lanigerum Hausmann) (Hom., Aphididae) and their distribution in Palatinate. Anzeiger fur Schadlingskunde, Pflanzenschutz, Umweltschutz, 62(2):25-31
Lee YI; Kwon GM; Lee SW; Ryu HK; Ryu OH, 1997. Observation on the fauna of arthropods from apple orchards in winter in Kyongbuk province. Korean Journal of Applied Entomology, 36(3):231-236.
Modic ?; ?kerlavaj V, 2008. The most important pests of apple and pear trees. (Pomembnej?i ?kodljivci jablan in hru?k.) SAD, Revija za Sadjarstvo, Vinogradni?tvo in Vinarstvo, 19(10):3-6. http://www.sad.si
Mols PJM, 1996. Do natural enemies control woolly apple aphid? International Conference on Integrated Fruit Production, at Cedzyna, Poland, 28 August-2 September 1995. Bulletin OILB SROP 1996, 19(4):203-207.
Mueller TF; Blommers LHM; Mols PJM, 1992. Woolly apple aphid (Eriosoma lanigerum Hausm., Hom., Aphididae) parasitism by Aphelinus mali Hal. (Hym., Aphelinidae) in relation to host stage and host colony size, shape and location. Journal of Applied Entomology, 114(2):143-154
Nel PJ; Addison MF, 1993. The development of an integrated pest management programme in apple orchards in Elgin, South Africa and the implications for integrated fruit production. Second international symposium on integrated fruit production, Veldhoven, Netherlands, August 24-28, 1992. Acta Horticulturae, 347:323-326.
Oppenheim D; Palevsky E; Horovitz I; Shaltiel L; Reuveny H; Aconis O, 1997. The influence of poison-free pest management on the fauna of arthropod pests and their natural enemies in an apple orchard at Havat Matityahu, Israel, during the seasons of 1994-96. Alon Hanotea, 51(8):346-356; 16 ref.
Palmer MA, 1952. Aphids of the Rocky Mountain Region. Colorado, USA: The Thomas Say Foundation.
Rupais AA, 1989. The aphids (Aphidoidea) of Latvia. Riga, Latvia: Latvian SSR Academy of Sciences Botanical Garden.
Shaw PW; Walker JTS; O'Callaghan M, 1996. Biological control of woolly apple aphid by Aphelinus mali in an integrated fruit production programme in Nelson. Proceedings of the Forty Ninth New Zealand Plant Protection Conference, Nelson, New Zealand, 13-15 August, 1996. Rotorua, New Zealand: New Zealand Plant Protection Society, 59-63.
Staubli A; Chapuis P, 1989. Protection of apple orchards against woolly aphid Eriosoma lanigerum Hausm. is it compatible with biological control of phytophagous mites? Revue Suisse de Viticulture, d'Arboriculture et d'Horticulture, 21(6):369-375
Sushma Bhardwaj; Chander R; Bhardwaj SP, 1995. Movement of woolly apple aphid (Eriosoma lanigerum) (Homoptera: Pemphigidae) on apple (Malus pumila) plant in relation to weather parameters. Indian Journal of Agricultural Sciences, 65(3):217-222; 6 ref.
Tejada M LO; Rumayor R OL, 1986. Phytosanitary study of apple cultivation (Malus sylvestris Mill) in the municipalities of Arteaga and Saltillo, Coahuila. Informe de Investigacion, Division de Ciencias Agropecuarias y Maritimas, Instituto Technologico y de Estudios Superiores de Monterrey, Mexico, No. 19:25-26
Thakur JN; Pawar AD; Rawat US, 1992. Apple woolly aphid, Eriosoma lanigerum Hausmann (Hemiptera: Aphididae) and post release impact of its natural enemies in Kullu Valley (H.P.). Plant Protection Bulletin (Faridabad), 44(3):18-20
Thwaite WG, 1997. Australia's Progress in Apple IPM. A Review of Integrated Pest Management in Australian Apple Orchards. Technical Bulletin NSW Agriculture. 48. Orange, Australia: NSW Agriculture Communications Unit, Research Liaison Officer (Scientific Publications).
Yu JiangNan; Chen WeiMin; Xu Yi; Liu XiaoLing, 2008. Bionomics and control of woolly apple aphid (Eriosoma lanigerum) in Ili River Valley. Xinjiang Agricultural Sciences, 45(2):298-301. http://www.xjnykx.periodicals.com.cn
Distribution MapsTop of page
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