Symptoms
- The initial symptom appears as yellowish brown spots with grey brown margins, usually they are oval in shape and measures approximately 1-5 cm long.
- As the disease advances the spots coalesce to form larger irregular necrotic patches with greyish white center.
- The symptoms are noticed in leaflets of the outer whorl and give a blighted appearance.
- In advanced stages the tips and margins of the leaf lets dry and shrivel giving a burnt appearance.
Procedure for Observation
Randomly select 20 palms from the garden. Observe the outer three whorls of leaves.
ETL
Moderate infection
Epidemiology
The disease is noticed in farms with poor nutritional status. Deficiency of potassium and excess of nitrogenous fertilizers favour the disease incidence.
Control Measures
- Balanced nutrient management.
- Remove the severely affected older leaves and burn.
- Spray the trees with 1% Bordeaux mixture or propiconazole (Tilt) 0.3%.
- Regular application of potassium chloride was reported to reduce the disease incidence.