Photo 1. Mines and adjacent damage along veins covering most of the leaves of bele caused by the bele leaf miner, Acrocercops sp.
There is no common name. Here it is called bele leafminer.
Acrocercops panall, a member of the Gracillariidae family. Acrocercops cathedrae is recorded from Papua New Guinea1.
World distribution unknown. Acrocercops species have been recorded from Australia, Fiji and Samoa.
The larvae cause extensive mining over large areas of the leaf (Photo 1&2). The mines often run alongside the veins at first. The damaged areas become paper-thin, bronzed and shiny.
The adult moth is about 4 mm long; wings are brown with three white bands aross them with black borders. The head is covered with silver scales. The young larvae are yellow; the mature larvae are red and 5 mm long. Pupation occurs in white cocoons in folds of leaves on weeds (broadleaved or grass) beneath the bele plants.
An important pest of bele and okra that is widely found in Fiji. Leaves that are mined are unlikely to be plucked for household use or sale in the market.
Look for the brown mines, most obvious on the topside of the leaves, often alongside veins, bordered by irregular paper-thin silvery areas, turning bronzed with age. Look for the damaged patches throughout the leaf rendering the leaves useless for household or market use.
Differences between varieties has not been reported but it is worth checking if the narrow leaf varieties suffer less damage then those with broad leaves.
Chemical control is difficult because the larvae are protected inside their mines, and pupae develop on weeds, not on bele. Also, insecticides are likely to destroy natural enemies, and this can lead to outbreaks of other insects, and also mites.
AUTHOR Grahame Jackson and Mani Mua
1Preston SR (1998) Aibika/Bele. Abelmoschus manihot (L.) Medik. Promoting the conservation and use of underutilized and neglected crops. 24. Institute of Plant Genetics and Crop Plant Research, Gatersleben/International Plant Genetic Resources Institute, Rome; and 2Swaine G (1971) Agricultural Zoology in Fiji. Her Majesty's Stationery Office. London, HMSO.
Produced with support from the Australian Centre for International Agricultural Research under project PC/2010/090: Strengthening integrated crop management research in the Pacific Islands in support of sustainable intensification of high-value crop production, implemented by the University of Queensland and the Secretariat of the Pacific Community.
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