EFFICACY OF COCONUT SHELL BIOCHAR WITH COW DUNG MANURE AND FERTILIZERS APPLICATION ON PRODUCTIVITY AND NUTRIENT CONTENT OF UPLAND RICE (ORYZA SATIVA) IN TYPIC HAPLUSTALF

Abstract

A field experiment was conducted to study the combined and individual application of coconut shell biochar (CSB) with cow dung manure (CDM) and NPK fertilizers on yield and nutrient content of upland rice in acid sandy loam Alfisol. The study was consisted of a RCBD design with sixteen treatments consisting of four levels of CSB at 2, 4, 6 and 8 t ha-1 and two levels of CDM at 5 and 10 t ha-1 with applied alone and in combinations with three replications. The recommended dose of NPK fertilizer (100:50:50 kg ha-1) was common except absolute control. Analysis of the data showed that the response of upland rice was described a better to combine the coconut shell biochar with cow dung manure and NPK fertilizers compared to sole application of biochar. Significantly higher upland rice grain (5784 kg ha-1) and straw yield (7624 kg ha-1) and nutrients (N, P, K, Ca, Mg, S, Fe, Cu, Zn and Mn) content in grain and straw was in the CSB, CDM and NPK fertilizers combined treatments. This results confirmed that sole application of coconut shell biochar not increased the upland rice productivity because of its high C : N ratio and low mineralization rate, hence, blending with cow dung manure could be reduced the high C:N ratio of coconut shell biochar. Since, cow dung manure is a good source of microorganisms and hastens the better mineralization rate and increased the efficiency of biochar to ameliorating the acid soils and make bio-availability of nutrients. This study indicates the necessity of combined application of biochar, manure and fertilizer for higher yield, reflecting and confirming the sustainable nutrient availability to upland rice.