Abstract

                                A field experiment was conducted at Coconut Research Station, Veppankulam during 2006-09 to asses the nutritional requirement of hybrid coconut (T x D) with 50 per cent nitrogen (N) substitution through organic manure. The experiment was conducted in 35 years old hybrid (T x D) palms (VHC 2). The experimental results proved that in hybrid coconut, a fertilizer level of 1000:250:2000 g NPK / Palm / year along with 50 kg of organic manure (Composted Coir Pith/ Vermi Compost) achieved economically higher mean annual nut yield, besides sustaining the soil fertility. While, the soil available NPK and index leaf NPK content was the highest at 1000:500:2000 g NPK/Palm / year. Considering consistent nut yield and sustainable soil health, 50 per cent of recommended N may be supplied through organic manure viz., vermicompost or composted coir pith and remaining 50 per cent N may be supplied through fertilizers. The organic manure that carries 50 per cent nitrogen can add organic matter to some extent in organically poor coastal coconut soils.

Key words : Hybrid coconut, waste recycling, nutrients renewal, N substitution.