Aceria chondrillae

Aceria chondrillae
Aceria chondrillae. Image by Charles Turner, USDA Agricultural Research Service, Bugwood.com
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Class: Arachnida
Family: Eriophyidae
Genus: Aceria
Species:
A. chondrillae
Binomial name
Aceria chondrillae
Synonyms

Eriophyes chondrillae

Aceria chondrillae[1] (chondrilla gall mite, skeletonweed gall mite) is a gall-forming deuterogynous eriophyid mite. It is often used as a biological control of the noxious weed Chondrilla juncea (rush skeletonweed),[2] a highly competitive herbaceous perennial composite found in Europe, Asia, Australia and North America.[3]

Biological description

At maturity, mites are yellowish orange in colour, with females ranging from 0.19-0.26 mm in length with the males slightly smaller at, 0.165-0.180 mm.[4] Except for genitalia male and female mites are externally similar. Larvae are smaller than the adults and distinguished by a humpback and exhibit no external genitalia. Eggs are soft, round, 0.04mm in diameter and at first colorless but later light orange. Mite growth and development is dependent on environmental and climatic conditions.[5] A. chondrillae have an average generation cycle of 10 days.[4]

Impact on chondrilla

The chondrilla plant exhibits galls when infested by A. chondrillae. These galls appear as clusters of tiny, hyperplastic buds[5] reaching a size of 1.5–2 cm in diameter, and in some cases up to 5 cm.[6] Hundreds of mites can be contained within each gall.

The development of the galls impede the health, growth, and reproduction abilities of the plant by:

  • destroying the flower buds in gall formation, reducing and suppressing seed production.
  • compromising the apical shoots, resulting in a diminished regenerative capacity. Particularly efficacious in plants infested early, gall formations block shoot development on the apical growing points, stunting growth, distorting adjacent stems, associated foliage and in some cases causing death.
  • weakening the plant through the presence and production of large galls. The plant often turns yellow early from premature decline.[3][5][7]

A. chondrillae has been recognized to affect plants of the Chondrilla genus: C. juncea, C. juncea f. acantholepis, C. brevirostris and C. leiosperma.[5]

Galls from Eriophyes chondrillae on Chondrilla. Image by Gary L. Piper, Washington State University, Bugwood.com
Chondrilla plant exhibiting galls from Eriophyes chondrillae. Image by Eric Coombs, Oregon Department of Agriculture, Bugwood.com

Use as a biological control

Aceria chondrillae is often used as a biological control for the perennial herb skeleton weed (Chondrilla juncea) present in Europe, North America and Australia. It was introduced to Australia in 1971 as part of a program to suppress skeleton weed in areas where it dominates the landscape.[8]

Predators

Only one predator of the Chondrilla gall mite has been observed in nature. The Phytoseiid predatory mite, Amblyseius sp., lives in the galls made by Aceria chondrillae and exists in all Mediterranean areas where Aceria chondrillae has been found. Populations are small and have little effect on A. chondrillae numbers.[5]

References

  1. ^ Aceria chondrillae at Australian Government's Department of the Environment and Water Resources
  2. ^ Chondrilla juncea at Washington State Noxious Weed Control Board
  3. ^ a b Krantz, G.W. and Ehrensing, D.T. (1990). ‘Deuterogyny in the Skeleton Weed Mite, Aceria Chondrillae (G. Can.) (Acari: Eriophyidae)’, International Journal of Acarology, Vol. 16, No 3, pp 129-133.
  4. ^ a b Powell G.W., Sturko A., Wikeem B.M., Harris P. (1994). ‘Field Guide to the Biological Control of Weeds in British Columbia’, British Columbia Ministry Forest Research Program Land Management, pp. 55-56.
  5. ^ a b c d e Caresche, L. A. and Wapshere, A. J. (1974). ‘Biology and host specificity of the Chondrilla gall mite Aceria chondrillae (G. Can.) (Acarina, Eriophyidae)’, Bulletin of Entomological Research, 64, pp 183-192.
  6. ^ Lindquist E.E., Sabelis M.W., Bruin J, (1996). ‘Eriophyoid Mites: Their Biology, Natural Enemies and Control’, Elsevier Science B.V., Vol 6, pp. 730.
  7. ^ Cullen, J. M. Groves, R. H. and Alex, J. F. (1982). ‘The Influence of Aceria chondrillae on the Growth and Reproductive Capacity of Chondrilla juncea’, Journal of Applied Ecology, Vol. 19, No. 2, pp. 529-537.
  8. ^ Cullen, J. M. and Moore, A. D. (1983). ‘The Influence of Three Populations of Aceria chondrillae on Three Forms of Chondrilla juncea’, Journal of Applied Ecology, Vol. 20, No. 1, pp. 235-243.