February 2014. An article on the coconut mite in Oman in the Oman Observer (http://main.omanobserver.om/?p=55501 )
A member wrote that he had seen similar symptoms on coconuts in Tonga in the 80s and 90s, when he worked there on coconut pests. He said that because the damage is not common and does not seem to affect the coconut meat or water there has been no research as to its cause.
A moderator said that he suspected that C. noahebridensis is widespread in the Pacific (possible represented by the image above in Port Vila, Vanuatu).
An email on C. novahedidensis was sent from the Coconut list.
It is present only in Darwin, Northern Territory, Australia. The New Hebrides coconut mite is recorded from Vanuatu, Costa Rica, Malaysia, Philippines and East Timor, but not previously in Australia.
The mite lives beneath the perianth of fruits where it feeds on meristematic tissue leading to surface scars, reduced fruit growth causing premature fruit fall. In East Timor, where it may have caused damage since the early 1950s, yield losses are estimated to be 2-3% of copra production.
The Northern Territory reported that the mite (Colomerus novahebridensis Kiefer) was detected in the Darwin Botanic Gardens on 19 May 2008 by an international mite expert. It was initially misdiagnosed as the coconut rust mite Aceria guerreronis Kiefer. Mites and their damage were subsequently detected on several established Malayan yellow dwarf coconut trees and four other locations within a 5 to 6 km radius of the first site. It is very likely that the mites have also spread elsewhere within the Darwin area. The planting of coconuts in the Northern Territory is generally for aesthetic reasons and there is little or no production value except for the nursery trade (estimated at in excess of $40,000 annually) and for the collection of nuts for drinking by the tourist trade.
Hugh Harries (Coconut list) sen the following articles and notes C. novahedridensis:
There is a photograph in a 1949 publication that shows coconut fruit scarring in Colombia that looks very much like mite damage (see attached mite damage.jpg)
- Martyn, E.B. (1949) Notes on a visit to Colombia: some observations on the diseases of coconuts and bananas in the Province of Magdelana. Tropical Agriculture (Trinidad) 26, 48-50.
Martyn did not mention mites, but said that he had seen similar damage in British Guiana (Guyana) in 1938 and had read about similar symptoms described as “Ring Disease of Immature Fruits” in New Guinea in 1937:
- Dwyer, R.E.P. (1937) The diseases of coconuts in New Guinea. New G. Agric. Gaz. 3 (1) 28-93.
In 1977, concerned by the increasing seriousness of coconut mite damage in West Africa, the Caribbean and South America, the Ministry of Overseas Development (ODM) in London and the Institut de Recherches pour les Huiles et Olagineux (IRHO) in Paris, jointly funded a preliminary programme of research into biological control of Eriophyes guerreronis (the generic nameAceria had been dropped), by making a survey of the Pacific and Indian Ocean areas, where the problem did not exist on the same scale.
In July 1978 the first project report drew attention to the presence of Colomerus novahebridensisfrom the Philippines to the New Hebrides (Vanuatu) and recommended that laboratory-reared mites could be used to test whether this mite may displace E.guerreronis. (see attached mite survey.pdf)
I don’t know if that test was ever made but the change in generic name, back to Aceria, may mean that the work reported on Eriophyes guerreroniswill be overlooked and forgotten!
The coconut mite, Aceria guerreronis
The mite was first reported in Guerrero, Mexico and now found in most of the coconut producing areas in South Asia, Central and South Africa, including the Gulf region. In Dhofar, it was reported in the late 1980s. “Agriculture scientists from all the affected countries are sharing information with each other to handle the issue in a positive manner,” said Anwar.
There is a good article on Aceria guerreronis from the University of Florida: http://entnemdept.ufl.edu/creatures/orn/palms/Aceria_guerreronis.htm.
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