Sulfur deficiency in coconut palm
Sulfur is an essential nutrient for protein synthesis, enzyme function, and chlorophyll formation in plants. Usually, Sulpher deficiency occurs in rare cases. In case of severe deficiency, it will affect plant growth.
Symptoms of Sulpher deficiency:
- Yellowish-green or yellowish-orange leaflets are typical visible symptoms.
- Older leaves remain green and leaves droop as the palm trunk becomes weak.
- Reduction in the number and size of leaves in older palms.
- Some times dead fronds develop around the stem like an apron(skirting of leaves) due to weak rachis.
- Immature nut fall occurs.
- The quality of Copra produced is inferior due to sulpher deficiency.
Causes of Sulfur Deficiency
- Sandy soils, highly leached soils, or areas with heavy rainfall may lack sulfur.
- Uptake Sulfur would be affected due to overuse of nitrogen or phosphorus fertilizers.
- Insufficient organic matter like compost, manure, or plant residues can deplete sulfur in the soil.
- Due to heavy rainfall sulfur may be leached off below the root zone
How to manage Sulfur Deficiency in coconut?
Determine the sulfur levels and overall nutrient balance and apply the right amount of sulfur as per the recommended dose.
In sulpher deficient gardens, soil application of gypsum 2 - 5 kg/tree/year or Root feeding of 0.2% gypsum is suggested as a general recommendation.
Application of any one of the Sulpher sources such as, Elemental Sulpher, Ammonium Sulfate( provides both sulfur and nitrogen), Gypsum(a source of sulfur, especially for alkaline soils).
Elemental Sulpher@ 50–75 g per palm/year is recommended generally for sulpher deficient gardens.
Foliar spray with a solution of potassium sulfate or magnesium sulfate (1–2% concentration) on the leaves in the case of severe deficiency.
The addition of organic matter like compost, and well-decomposed manure, can help release sulfur naturally, along with other essential nutrients.
Avoid water logging, which can reduce nutrient uptake by the roots, including sulfur.
The deficiency of sulfur shall be corrected easily by adopting the above corrective measures to ensure healthy coconut palms and superior quality nut and copra.
