Investigation of biochar applications to reduce adverse effects of boron (B) toxicity in wheat plants

This study was conducted to evaluate the effects of rice husk biochar (BC) on growth and nutrient uptake of wheat (Triticum aestivum L. cv. Basilio) under increasing boron (B) toxicity conditions. The experiment was carried out under climate chamber conditions using a factorial combination of three boron doses (0, 5 and 10 mg B kg⁻¹) and three biochar levels (0%, 1%, and 2%). Root and shoot dry matter yields, as well as B, N, P, K, Zn, and Fe concentrations, were determined, and the data were analyzed using one-way analysis of variance (ANOVA) and Duncan's multiple range test. The results revealed that increasing boron doses inhibited root and shoot growth in wheat plants, whereas biochar applications significantly alleviated these adverse effects. In particular, the 2% biochar treatment increased root dry matter by 33% and shoot dry matter by 18% under boron toxicity. Moreover, biochar reduced B concentrations in roots and shoots by 37% and 65%, respectively, thereby limiting toxic boron accumulation. The ameliorative effect of biochar was attributed to its high surface area, negatively charged functional groups, pH buffering capacity, activation of antioxidative defense systems, and stimulation of rhizosphere biota. Overall, rice husk biochar demonstrates substantial potential as a sustainable organic amendment for mitigating boron toxicity in agricultural soils.