(Kerner, 1778)
Diagnosis
In life, scale cover of adult female 1.5-2.5 mm diameter, circular and slightly convex, semitransparent dirty white or tan with yellow or tan subcentral exuviae DIABRL1.jpg . Male scale cover white, elongate, tricarinate, with terminal yellow exuviae (Gill, 1997) DIABRL1.jpg and DIABRL.jpg . Eggs yellow; the male is winged (Murray, 1980).
Body of slide-mounted adult female less than twice as long as wide, body widest at prothorax or head; a pair of lateral tubercles present on prosoma DIABRS.jpg . Pygidium with median lobes not zygotic, set well apart and inset to form an apical notch, with a pair of setae between their bases; bases of marginal segmental setae on pygidium not obviously enlarged and sclerotized; submedian macroducts absent from pygidium; 7-10 submarginal macroducts as big as marginal macroducts, present on each side of pygidium DIABRP.jpg .
The first instar female and first and second instar male nymphs were described by Howell, 1975.
Host range
Diaspis bromeliae is quite polyphagous, and was recorded from hosts belonging to 10 plant families (Borchsenius, 1966); however, Davidson and Miller, 1990, attribute it with hosts in 10 genera belonging to two families and say that they suspect many other host records are erroneous. Pineapple, Bromeliaceae and other epiphytes are particularly favoured hosts. Hosts include species of: Aechmea, Agave, Ananas comosus, Ananas sativus, Anthericum, Billbergia, Brassia, Bromelia, Bromeliaceae, Canna, Chamaerops, Hedera, Hibiscus, Jodina, Nidularium, Ocotea, Oncidium, Osmanthus, Palmae, Phoenix, Saccharum and Tillandsia.
Affected plant stages: vegetative growing, flowering, fruiting and post-harvest stages
Affected plant parts: on the leaves DIABRL2.jpg , and sometimes on fruit DIABRL3.jpg and stems
Biology and ecology
Reproduction is sexual, and in tropical conditions there are continuous generations. There are probably multiple generations each year (Gill, 1997). In Australia, D. bromeliae takes two months to develop from egg to adult (Murray, 1980). It usually occurs on parts of pineapple plants in the dense growth near the centre of the field, which are shaded most of the time (Collins, 1968; Murray, 1980).
Crawlers are the primary dispersal stage and move to new areas of the plant or are dispersed by wind or animal contact. Mortality due to abiotic factors is high in this stage. Dispersal of sessile adults and eggs occurs through human transport of infested plant material.
Symptoms
Heavy infestations cover the plant in a light grey, scurfy coating. The most obvious damage is the formation of chlorotic spots where the scales feed. Heavily infested plants may become weak and stunted, with dieback of the foliage; they produce undersized, pinched-looking fruit (Murray, 1980).
Economic impact
Diaspis bromeliae is known as a pest of pineapples but its pest status is not fully understood (Williams and Watson, 1988). Danzig and Pellizzari, 1998, describe it as a pest. Foldi, 2001, lists this species as an occasional pest in France, and Gill, 1997, describes it as a minor pest of pineapples in some tropical areas.
Detection and inspection methods
Peel off and examine leaves, especially from the basal part of the plant, for circular, slightly convex, semi-transparent dirty white or tan scale covers with yellow or tan subcentral exuviae.
Phytosanitary protection
Diaspis bromeliae is mentioned on quarantine lists (Burger and Ulenberg, 1990). Infested planting material is the source of virtually all new outbreaks of D. bromeliae, so growers should ensure that the pest is not introduced with plant material. Heavily infested plants should be burned (Murray, 1980).
Natural enemies
Parasitoids:
- Aphytis sp., in South Africa, Australia (Queensland)
- Coccidencyrtus ochraceipes, in South Africa
- Encarsia sp., in South Africa, Australia (Queensland)
Predators
- Orcus sp., in Australia (Queensland)
- Rhyzobius lophanthae, in South Africa, Australia (Queensland)
- Rhyzobius sp., in Australia (Queensland)
Distribution
See Diaspis bromeliae distribution.
Microscopic examination of slide-mounted adult females is required for authoritative identification to species.
Diaspis boisduvalii is often found on pineapple, where it could be confused with D. bromeliae; however, D. boisduvalii has only 2 enlarged submarginal macroducts on each side of the pygidium, whereas in D. bromeliae there are 6 or more on each side.
Comments
Diaspis bromeliae is a tropical species, probably of New World origin. In northern countries, this species occurs under glass (Danzig and Pellizzari, 1998). In spite of the record published by Nakahara, 1982, D. bromeliae is not established in the United Kingdom (C.P. Malumphy, Central Science Laboratory, UK, pers. comm.).
Europe
Austria: The Natural History Museum collection, London, UK
Belgium: under glass (Nakahara, 1982)
Denmark: present, no further details (Nakahara, 1982)
Former Czechoslovakia: present, no further details (Nakahara, 1982)
Former USSR: under glass (Nakahara, 1982; Danzig and Pellizzari, 1998)
France: possibly present under glass (Foldi, 2001)
Germany: present, no further details (Nakahara, 1982)
Hungary: present, no further details (Nakahara, 1982)
Italy: present, no further details (Longo et al., 1995; Danzig and Pellizzari, 1998)
Sicily: present, no further details (Longo et al., 1995)
Malta: present, no further details (Danzig and Pellizzari, 1998)
Netherlands: present, no further details (Nakahara, 1982)
Poland: present, no further details (Nakahara, 1982)
Portugal: present, no further details (Danzig and Pellizzari, 1998)
Azores: present, no further details (Nakahara, 1982)
Madeira Is: present, no further details (Nakahara, 1982)
Spain
Canary Is: present, no further details (Carnero Hernandez and Perez Guerra, 1986; Danzig and Pellizzari, 1998)
Sweden: present, no further details (Nakahara, 1982)
Switzerland: present (Kozár and Hippe, 1996)
Asia
China: present, no further details (Danzig and Pellizzari, 1998)
South China: present, no further details (Tao, 1999)
India: present, no further details (Hayes, 1970)
Japan: present, no further details (Kawai, 1980; Tao, 1999)
Okinawa: present, no further details (Nakahara, 1982)
Korea: present, no further details (Danzig and Pellizzari, 1998)
Malaysia
West Malaysia: present, no further details (Yunus and Ho, 1970; CIE, 1973)
Myanmar: present, no further details (Tao, 1999)
Philippines: present, no further details (Nakahara, 1982)
Ryukyu Is: present, no further details (CIE, 1973)
Taiwan: present, no further details (Wong et al., 1999; Danzig and Pellizzari, 1998)
Turkey: present, no further details (Danzig and Pellizzari, 1998)
Africa
Egypt: present, no further details (Nakahara, 1982; Danzig and Pellizzari, 1998)
Kenya: present, no further details (Nakahara, 1982)
Mauritius: present, no further details (Williams and Williams, 1988; Danzig and Pellizzari, 1998)
Morocco: present, no further details (Nakahara, 1982)
Mozambique: present, no further details (Nakahara, 1982)
Seychelles: present, no further details (Nakahara, 1982)
Siera Leone: present, no further details (Nakahara, 1982)
South Africa: present, no further details (Nakahara, 1982; Danzig and Pellizzari, 1998)
St Helena: The Natural History Museum collection, London, UK
Western Hemisphere
Antigua: present, no further details (Nakahara, 1982)
Argentina: present, no further details (Nakahara, 1982)
Buenos Aires: present, no further details (Claps et al., 2001a)
Córdoba: present, no further details (Claps et al., 2001a)
Salta: present, no further details (Claps et al., 2001a)
Tucumán: present, no further details (Claps et al., 2001a)
Bahamas: present, no further details (Nakahara, 1982)
Brazil: present, no further details (Nakahara, 1982; Williams and Greathead, 1990)
Bahia: present, no further details (Claps et al., 2001a)
Minas Gerais: present, no further details (Claps et al., 2001a)
Rio de Janeiro: present, no further details (Claps et al., 2001a)
Rio Grande do Sul: present, no further details (Claps et al., 2001a)
Sao Paulo: present, no further details (Claps et al., 2001a)
Belize: present, no further details (Nakahara, 1982)
Central America: present, no further details (Danzig and Pellizzari, 1998)
Colombia: present, no further details (Nakahara, 1982; Kondo, 2001)
Cuba: present, no further details (Nakahara, 1982)
Costa Rica: present, no further details (Nakahara, 1982)
Dominica: present, no further details (Nakahara, 1982)
Dominican Republic: present, no further details (Nakahara, 1982)
Guadeloupe: present, no further details (Nakahara, 1982)
Guatemala: present, no further details (Nakahara, 1982)
Guyana: present, no further details (Nakahara, 1982)
Haiti: present, no further details (Nakahara, 1982)
Jamaica: present, no further details (Nakahara, 1982)
Martinique: present, no further details (Nakahara, 1982)
Mexico: present, no further details (Nakahara, 1982; Miller, 1996)
Puerto Rico: present, no further details (Nakahara, 1982)
St Lucia: present, no further details (Nakahara, 1982)
St Vincent: present, no further details (Nakahara, 1982)
Trinidad: present, no further details (Nakahara, 1982)
USA: under glass in colder areas (Nakahara, 1982)
California: occasionally found in greenhouses (Gill, 1997)
District of Colombia: present, no further details (Nakahara, 1982)
Florida: present, no further details (Nakahara, 1982)
Hawaii: widespread (Heu, 2002)
Illinois: present, no further details (Nakahara, 1982)
Missouri: present, no further details (Nakahara, 1982)
New Jersey: present, no further details (Nakahara, 1982)
New York: present, no further details (Nakahara, 1982)
Ohio: present, no further details (Nakahara, 1982)
Pennsylvania: present, no further details (Nakahara, 1982)
Venezuela: present, no further details (Nakahara, 1982)
Virgin Is: present (CIE, 1973)
Oceania
Australia
New South Wales: present, no further details (CSIRO, 2001)
Queensland: present, no further details (Murray, 1980; CSIRO, 2001)
Bonin Is: present, no further details (Nakahara, 1982)
Caroline Is: present (CIE, 1973)
Cook Is: present (Williams and Watson, 1988)
Fiji: present, no further details (Nakahara, 1982)
New Caledonia: present, no further details (Nakahara, 1982)
Pitcairn I.: present, no further details (Nakahara, 1982)
Pohnpei: present, no further details (Nakahara, 1982; Beardsley, 1966)
Samoa: present, no further details (Nakahara, 1982)
Tahiti: present (Williams and Watson, 1988)
Western Samoa: present (Williams and Watson, 1988)