Summary

Narrow distribution. In Oceania, Fiji, New Zealand, Niue, Samoa, Tonga. Recorded from coconuts, ginger, taro, yam.
Damage: not likely. Previously thought to be of economic importance because two near relatives injure bulbs, corms, tubers of e.g., onion, garlic, gladiolus, hyacinth, lilies, potato, carrot in storage, as well as attacking roots of onion, garlic and cereals in the field. They also allow entry of Fusarium.
Adult about 0.4 mm long, white with brown legs; lays several hundred eggs; nymphs with 6 legs, then several nymph stages when legs increase to four pairs and the mites become sexually mature.
Spread: attach to insects visiting the decaying storage organs; long distance in domestic and international trade.
Cultural and Chemical controls: Surveys in Australia and New Zealand failed to detect the mite, so although it has had the chance to establish, it had failed to do so. It appears, therefore, that there are no potentially adverse economic consequences from the importation of taro where this mite is present. Neither country considers Rhizoglyphus minutus a quarantine pest.

Common Name

Taro bulb mite

Scientific Name

Rhizoglyphus minutus

AUTHOR Grahame Jackson
Information from Zhang Z-Q et al. (2004) Current status of research on Rhizoglyphus mites associated with taro. SPC Third Taro Symposium: 21-23 May 2003: Nadi, Fiji Islands; and Biosecurity Australia (2011) Review of import conditions for fresh taro corms. Biosecurity Australia, Canberra; Diaz A et al. (2000) Biology, ecology, and management of the bulb mites of the genus Rhizoglyphus (Acari: Acaridae). Experimental and Applied Acarology 24: 85–113; and Bulbmites. University of Florida/IFAS Pest Control Guides. (https://mrec.ifas.ufl.edu/foliage/entomol/ncstate/mite2.htm); and from Zhang Z (2004) Of mites and quarantine: a story of two crops. Te Taiao 3: 12–13. (http://www.landcareresearch.co.nz/publications/newsletters/tetaiao/TeTaiaoIssue3.pdf). Photo 1&2 MAF Plant Health & Environment Laboratory (2011) Bulb Mite (Rhizoglyphus minutus). Updated 2014. PaDIL - http://www.padil.gov.au.

Produced with support from the Australian Centre for International Agricultural Research under project HORT/2016/18: Responding to emerging pest and disease threats to horticulture in the Pacific islands, implemented by the University of Queensland and the Pacific Community.

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