Effect of Biochar on Arbuscular Mycorrhizae Fungi, Nutrient Uptake and Growth of Local Upland Rice, Southeast Sulawesi, Indonesia

Abstract

Biochar has the capacity to influence soil fertility, mycorrhizal arbuscular fungi (AMF), and upland rice growth. Therefore, this study aimed to assess biochar addition on soil character and investigate the effect on AMF, growth, yield, and nutrient uptake of upland rice local. Four levels biochar rate (%, w/w) of 0%, 2.5%, 5.0%, and 7.5% was tested in a pot experiment. The results showed that pH, C-org, tot-N, and C and N-ratio increased linearly, while P-available quadratic, and K-exchange increased exponentially with biochar rate. At 60 and 90 days after planting, the height of a plant containing 7.5% biochar was significantly high. The roots and shoots ratio showed the highest and lowest values at 0% and 7.5% biochar rates. Furthermore, the filled spikelet percentage at a 5.0% was the most significant among the others. The biochar rate increased the straw P and K uptake, but N was insignificant and N and P ratio was decreased. Total AMF spores were reduced with biochar addition, and the difference in the proportion of infected roots was not statistically significant. There was a positive correlation between total spikelet per panicle with P and K uptake and a negative correlation with N and P ratio and total AMF spore. The filled spikelet negatively correlated with K uptake, and biochar addition to soil fertility increased. The 5% addition had a better effect on yield component and nutrient uptake of P and K by the local upland rice on acidic soil.