Effects of Compound Fertilizer on Growth, Yield and Economic Efficiency of Robusta Coffee in Basalt Soil of Dak Lak Province

Abstract

      Field fertilizer experiments were conducted to identify the most effective dosage of compound fertilizer with 6 different levels applied to Robusta coffee in basalt soil of Dak Lak province from 2012 to 2014. All experiment plots applied with compound fertilizer of Yara company were compared with 260kg N + 95kg P₂O₅ + 240kg K₂O and 10 tons of manure (application at 2-year interval) applied for Robusta coffee as recommended by the Ministry of Agriculture and Rural Development (control 1). The results showed that application of 2,100 kg compound fertilizers per ha per year significantly increased soil fertility as evidenced by increased contents of total nitrogen, available phosphorus, and available potassium, Ca and Mg in soils. Moreover, the length of reserve branches increased by 20%, 100 fruit weight by 18%, and coffee bean productivity per ha by 21%, but fresh coffee/coffee bean reduced by 14%. The rate 2,100 kg compound fertilizers/ha/year also gave the higher gross value (VND 139.46 millions/ha/year) and higher economic efficiency (profit of VND 62.52 millions/ha/year) in comparison with the recommended practice.