Analysis of Material Properties with Biochar Improve Indian Mustard (Brassica juncea) Growth in Acidic Soil in Northern China

Two biochars were prepared at 400 °C from peanut shell and Chinese medicine material residue, and their surface properties were measured by scanning electron microscopy (SEM) and electron dispersive X-ray analysis (EDX). The two biochars were mixed at a ratio of 1:1, and then was applied to an acidic soil collected from a cropland in Huangdao district of Qingdao, Shandong province, China. The results of soil incubation and pot experiments showed that biochar applications to the acidic soil (1% and 5%) increased pH value from 5.8 to 6.1 and 6.7, improved Indian mustard (Brassica juncea) seed germination rate by 10% and 15%, respectively, and the shoot and root dry weight were significantly increased by 8.3%/28.5% and 11.5%/26.9%.