Leaf symptoms
These are some of the symptoms you might see on coconut leaves (including the leafstalk). Click on the possible causes of the symptoms to find out more.
Remember that poor nutrition can cause yellowing of palms, so nutritional analysis should be undertaken along with disease diagnostics. Also weather conditions (e.g., drought) can cause leaves to shrivel and dry out. Consider these factors as possible causes of symptoms also.
Symptom |
Possible cause |
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Healthy leaf (left) vs. diseased leaf with distinctive mottled yellowing (right) (© Dagmar Hanold and John Randles, Waite Agricultural Research Institute) |
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Sooty mould growth from honeydew secretions, surrounding woolly insect colonies at the base of a frond (© Lyle J. Buss, University of Florida) |
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Sooty mould growth from surrounding woolly insect colonies and honeydew secretions (© Lyle J. Buss, University of Florida) |
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Caterpillar feeding resulting in light grey lines or "windows" with exposed leaf skeleton (© PestNet) |
Additional symptoms of coconut flat moth include:
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Leaflets showing brown, burnt looking decay (© PestNet) |
Additional symptoms of coconut hispine beetle include:
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Brown narrow furrows along leaves. Adult beetles may be seen feeding and leaving the furrows behind (© Jean-Pierre Labouisse, CIRAD) |
Additional symptoms of coconut leaf miner include:
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Damage on leaves that is brown to grey and appears burnt or decayed (© Jean-Pierre Labouisse, CIRAD) |
Additional symptoms of coconut leaf miner include:
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Bored holes at the base of the fronds (© Pacific Biosecurity) |
Coconut rhinoceros beetle - Oryctes rhinoceros Additional symptoms of coconut rhinoceros beetle include:
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V shaped feeding damage on fronds (© Pacific Biosecurity) |
Coconut rhinoceros beetle - Oryctes rhinoceros Additional symptoms of coconut rhinoceros beetle include:
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Palm frond leaflets look squeezed and crushed together while the fronds show twisting, nicks and truncation (© Department of Agriculture and Water Resources, Australia) |
Melanesian coconut rhinoceros beetle Additional symptoms of Melanesian coconut rhinoceros beetle include:
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Yellow spots concentrated on an area of a leaf. Note the brown spots starting to appear (© TNAU) |
Coconut scale | |
A leaf with a crusted surface. A closer look may show a heavy yellow-orange scale insect colony (© TNAU) |
Coconut scale | |
Leaf tissues looking yellowed or brown and wilted, especially near the tip of the frond (© Merle Shepard and Gerald Carner, Clemson University) |
Coconut scale | |
Yellowing and following death of leaflets from the tip of the diseased frond (© Geoff Gurr, Charles Sturt University) |
Finschhafen disorder | |
Malayan Dwarf variety showing red-greyish brown leaves throughout green healthy leaves (© Nigel A. Harrison, University of Florida) |
Additional symptoms of lethal yellowing include:
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Yellow splotches on leaves that may have turned brown and yellowing of the midrib (© Jorge Peña, University of Florida) |
Red palm mite | |
Straight edged of leaves rather than pointed tips (© International Palm Society) |
Additional symptoms of palm weevil include:
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