Integrated nutrient management in COD x WCT hybrid coconut under alluvial clay-loam soil of Assam

Abstract

A field experiment was conducted in alluvial clay-loam soil at the Horticultural Research Station, Kahikuchi of Assam Agricultural University under All India Co-ordinated Research Project on Palms from 2003 to 2007 to study the effect of integrated nutrient management treatments on COD x WCT hybrid coconut taking 27 treatment combinations with three levels each of N (0, 500, 1000 g/palm/year, where 50% N was substituted by vermicompost on N equal nutrient basis), P₂O₅ (0, 250, 500 g/palm/year) and K₂O (0, 1000, 2000 g/palm/year). The results revealed significant influence of the integrated nutrient treatments on number of functional leaves in the crown, number of female flowers, nut setting, nut yield per palm per year and copra content per nut. The highest values for all these characters were obtained under higher level of K application. However, the highest average nut yield of 111nuts/palm/year and benefit cost ratio of 2.02 were recorded in the treatment N₁P₂K₂ (500 g N wherein 50% N substituted by vermicompost, 500 g P₂O₅ and 2000 g K₂O/palm/year), while the lowest nut yield (44 nuts/palm/year) and benefit cost ratio of 0.20 were recorded in the treatment N₀P₀K₀ and N₂P₂K_0, respectively. The integrated nutrient treatments also improved the soil pH, organic carbon content, available N, P and K content of the soil and the leaf NPK contents of the palms under study.