Areca nut Special Micronutrient

Nutritional Disorders in Areca nut and their Management

Areca nut palms are often affected by nutritional disorders such as crown choking, crown bending, oblique node formation, and nut splitting (nut spitting), which can significantly reduce palm vigour and productivity. These disorders are commonly observed in areas with excessive soil fertility, poor drainage, water stagnation, and in lands converted from paddy cultivation.

Symptoms and Causes

Crown choking is one of the earliest visible symptoms and is characterized by the emergence of dark green, erect leaves with reduced leaf size. The condition is primarily associated with zinc deficiency, which is often aggravated by excessive levels of nitrogen, phosphorus, and other nutrients that interfere with zinc uptake by the palm.

Crown bending generally results from a combined deficiency of zinc and calcium, affecting normal leaf and crown development.

Nut splitting is mainly caused by potassium deficiency. Since potassium is essential for the proper development of both the husk and kernel, inadequate potassium supply can lead to poor nut formation and splitting.

Corrective Measures

For palms showing early signs of nutritional disorders, soil application of zinc sulphate at 10 g per palm can help restore nutrient balance. In cases of severe crown choking and marked reduction in leaf size, foliar spraying of 0.5% zinc sulphate solution (5 g per liter of water) on newly emerging leaves is recommended to promote normal leaf growth and recovery.

To address nut splitting, adequate potassium nutrition should be ensured through recommended fertilizer applications and organic potassium sources.

Advisory for Farmers

• Conduct soil testing before planting and at least once every three years thereafter.
• Avoid collecting soil samples from interspaces; samples should be taken from the active root zone.
• Apply fertilizers during the post-monsoon season, when palm growth is most active and nutrient uptake is highest.
• Avoid relying solely on urea or organic manures that primarily supply nitrogen.
• Pay special attention to potassium and zinc nutrition, as deficiencies of these nutrients are increasingly reported in lateritic soils of major areca nut-growing regions.
• Supplement potassium through sources such as Muriate of Potash (MOP), areca nut husk, coconut coir pith, and Gliricidia biomass.
• As a preventive measure, zinc sulphate at 10 g per palm may be applied once every three years to reduce the incidence of nutrient-related disorders.

Proper nutrient management and regular monitoring can effectively prevent these disorders and ensure healthy palm growth, improved nut quality, and sustained productivity.