Rice husk biochar application and the planting times effects on dry weight and water use efficiency of upland rice varieties

Abstract

The objective of this study was to measure the effect of rice husk biochar application and the planting times on dry weight and water use efficiency of upland rice varieties at Zone D Oldeman Agroclimate in North Sumatra Indonesia. First factor as main plot was the planting times such as planting. Second factor as sub plot was upland rice varieties such as Batutegi, Inpago 4, Limboto, Situbagendit and Situpatenggang. Third factor as sub sub plot was type of rice husk biochar application such as no rice husk biochar (RHB), RHB, RHB + Chicken manure, RHB + EM4. Result showed that rice husk biochar (with chicken manure or EM4) increased upland rice dry weight (1-17%) and water use efficiency (17-25 %) in planting times of August and September and increased more higher in planting time of June and July about 17-25 %, 61-80 % respectively and rice husk biochar application decreased water use efficiency only in planting time of August. Batutegi and Inpago 4 varieties showed the highest dry weight and the highest value of water use efficiency were Inpago 4 and Limboto. Planting time of August or September showed the highest upland dry weight and water use efficiency.