Utilization of cacao shell biochar and compost to improve cayenne pepper (Capsicum frutescens L.) in acid upland

Abstract

Acid upland is considered a potential area for horticulture crop such as cayenne pepper (Capsicum frutescens L.). This study aimed to evaluate the effects of the use of cacao shell biochar and compost to soil properties and the productivity of cayenne pepper in acid upland. This research was conducted in Taman Bogo research station, Lampung Province, Indonesia in 2017. This research used a randomized block design with seven treatments and three replications. The treatments consisted of P0: control (no soil ameliorant and mulch), P1: biochar 20 t ha-1, P2: P1+ mulch, P3: compost 20 t ha-1, P4: P3+mulch, P5: biochar+compost (1:1) 20 t ha-1, and P6: P5+mulch. The raw material of biochar was cacao shell, while compost was manure. The result showed that soil bulk density of biochar, compost, and a combination of biochar and compost treatment lower than control. Biochar with and without compost have soil water content higher than other treatments. Moreover, biochar with and without compost were increase pH, reduce exchangeable Al level, increase C and N content also increase cation exchange capacity (CEC) and base saturation. The use of biochar and compost had positive effects on plant height, the diameter of canopies, and crop yields.