Compost for Nitrogen Fertility Management of Bell Pepper in a Drip-irrigated Plasticulture System

Abstract

Two types of commercial compost produced from manure and food waste or brewery waste solids were tested for supplying the N requirements of a bell pepper crop in a drip-irrigated plasticulture system over two seasons. Composts were tested at 40 and 80 Mg·ha-1, and combined with 67 and 133 or 0 and 67 kg·ha–1 N applied as mineral fertilizer in the first and second seasons, respectively. Both types of compost increased total soil carbon and N content relative to unamended soil. Compost amendment also increased soil NO3-N, NH4-N and N mineralization potential throughout the season, but yields were not affected. Increasing compost amendment rate from 40 to 80 Mg·ha–1 did not increase N levels in soil or plants. Yield was not affected and season biomass accumulation was inconsistently affected by compost amendment. Commercial composts thus released mineral N in the first year of application, but supplementation with mineral fertilizer may be necessary depending on seasonal variation of N release and crop need.