Optimization of macronutrients application in Terminalia tomentosa (Asan) for sustainable tasar silk production

Abstract

Aim: The aim of the present study was to optimise the nutrient requirements for Terminalia tomentosa (Asan) plant to increase the quality and quantity of leaves. Methodology: This study used the Mitscherlich-Bray equation to formulate NPK requirements for the Asan plant. Independent experimental setups of N (5 levels), P (5 levels), and K (5 levels) designed in RCBD with three replications were carried out concurrently. Calculations were made to determine the theoretical maximum yield, the NPK constants c and c1, the NPK fertiliser recommendations for the Asan plant at various soil fertility levels, and the ideal fertiliser rates. Results: Fertiliser recommendations were developed for a typical range of soil test values, but they still required additional field verification tests. The theoretical maximum yields determined by the Mitscherlich-Bray equation were 599.79g, 587.49 g, and 562.34 g per 50 leaves of the Asan plant for NPK, respectively. The study demonstrated that it is critical to consider the inherent soil fertility when developing fertiliser recommendations for Asan that will increase both leaf yield and overall productivity. It showed that soil K was less efficiently utilised by the Asan plant compared to the other soil nutrients. The c1/c ratio of the P experiment was lowest compared to the c1/c ratio values of N and K experiments, indicating that the Asan plant was more responsive to P fertilisation than other macronutrient fertilisation Interpretation: The fertiliser recommendation chart serves the farmers to manage the Asan plants and is more beneficial for harvesting quality cocoons without degrading the ecosystem. Key words: Asan, Baripada, Macronutrients, Odisha, Tasar silk