Leaves with dead edges or patches
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Manganese toxicity (dead patches)
Cause: Excess manganese in the plant due to the presence of manganese nodules in the soil profile and water-logging.
Solution: Confirm the diagnosis with a leaf analysis. Improve soil drainage and soil structure. Avoid planting bananas in poorly drained soils.
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Salt toxicity (dead edges)
Cause: A build-up of salt in the plant from high soil or water salinity.
Solution: Confirm the diagnosis with tissue or water analysis. Water heavily to leach salt out of the root zone. Seek alternative sources of water. Avoid excessive applications of fertilisers containing chloride.
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Mites (dead edges)
Cause: Feeding of the banana spider mite Tetranychus lambi, or the two-spotted mite, Tetranychus urticae on the underside of leaves. Severe outbreaks are usually the result of poor insecticide management which has destroyed beneficial insects.
Solution: Treat with an appropriate miticide. Ensure adequate coverage to the underside of the leaves.
More info:
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Water stress (dead patches)
Cause: Severe water stress during hot, dry periods.
Solution: Apply more water during periods of high demand. Water scheduling devices help to plan irrigation.
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