Biochar improves soil quality. However, most biochar research has focused on aerobic soil conditions. The objective of this research was to evaluate the agronomic benefits of applying biochar on unfertilized rice crop, cultivated under transitional anaerobic soil conditions during early vegetative growth phase, and gradually drying out to fully aerobic at harvest time. This transitional condition is typical during the rice growing season of the tropical riparian wetlands in Indonesia. Biochar was applied in the form of fine powder at rates of 0, 0.4, 0.8, and 1.2 Mg.ha-1; no inorganic fertilizer was applied. The research was conducted on a farmer’s paddy field at Pemulutan Ulu Village, South Sumatra, Indonesia from July to November 2016. Results indicated that applying biochar at rates up to 1.2 Mg.ha-1 increased rice yield, but restrained shoot elongation rate and plant height. During the vegetative growth phase, applying biochar significantly increased the number of tillers, leaves, shoot dry weight, and root dry weight. Biochar significantly affected the following yield components: number of tillers, percentage of productive tiller, number of grains per panicle, panicle density, percentage of filled grain, and weight of 1,000 grains.
Full article can be downloaded here: 2018 CMUJ Natural Sciences 17(2)_111-126 Benefits on rice