Mitigation of Button Shedding in Coconut through Nutritional and Hormonal Interventions

Abstract

Background: Coconut is a vital perennial tropical crop with major global and socio-economic importance, but its productivity is affected by climatic stress, nutritional deficiencies, and severe button shedding that significantly reduces yield. Button shedding varies from year to year within a variety and it is greater in dwarf palms compared to tall palms. Shedding of buttons and immature nuts may be due to nutritional and hormonal deficiency, pests and diseases, unfavorable environmental conditions, lack of drainage, pollination, and genetic conditions. Aim: The aim of this study was to evaluate the efficiency of growth regulators and nutrients for the management of button shedding in coconut. Study Design: The experiment was conducted in a Randomized Complete Block Design. Place and Duration of Study: The study was conducted at the Coconut Research Station, Balaramapuram, Kerala, India. Methodology: A survey was conducted to select the West Coast Tall (WCT) palms with uniform age showing significant button shedding. The respective solutions as per different treatments fixed for the study were prepared and administered to the palms through root feeding technique. After imparting different treatments via root feeding, the number of buttons retained in the newly opened inflorescence, biochemical, physiological and yield parameters were observed and recorded for a period of first six months. This was the first report of using Hoagland solution (2X) for the management of button shedding in coconut. Results: Among the seven treatments, T2 (Hoagland Solution - 2X) showed the lowest button shedding percentage which was followed by T6 (Salicylic Acid - 200 ppm) and T5 (Borax (0.5 g) + 2, 4-D (50 ppm) during the first four months after root feeding. T2 treated palms exhibited the highest photosynthetic and transpiration rates over the six-month period, indicating enhanced physiological performance. Both T2 and T6 treatments maintained higher carbohydrate levels than the control throughout the study. In addition, macronutrient (N, K, Ca, Mg, S) and micronutrient (Fe, Zn, Cu, B, Mn) contents were consistently greater in T2-treated palms, reflecting improved nutritional status and better nut retention following root feeding. Conclusion: The reduction in button shedding observed in treatments T2, T6, and T5 was closely associated with increased carbohydrate accumulation and enhanced macro- and micronutrient contents in the leaves following root feeding. These improvements indicate that better nutritional status and elevated physiological activity contributed to improved button retention. Overall, the results demonstrate that root feeding with balanced nutrients and growth regulators enhances photosynthetic efficiency, nutrient uptake, and metabolic activity in coconut palms, thereby minimizing early nut drop. This study highlights the effectiveness of Hoagland solution and salicylic acid as practical interventions to improve palm health and reduce button shedding, ultimately supporting higher nut retention and productivity.