Morphophysiological response of Cerrado plants to filter cake biochar application

Abstract

Some native species of the Cerrado have great ecological and economic potential. An alternative that aims to contribute to the good performance of post-planting plants is the incorporation of biochar into the soil. The objective of this work was to evaluate the effect of filter cake biochar as a soil conditioner and its influence on the growth and physiology of macaúba, araçá and cajuzinho do cerrado. The experiments were set up at Fazenda Hamilton de Abreu Navarro, Federal University of Minas Gerais, where the effect of four doses of filter cake biochar (1%, 2%, 4% and 8% v/v) and two treatments were evaluated. control: one with soil correction (7.5 g of GEOX) and mineral fertilization (380 g NPK 4:14:8 per plant) and the other without fertilization. To monitor the performance of the seedlings, evaluations were carried out at 30, 60 and 120 days after transplanting, the physiological parameters (photosynthesis, transpiration, stomatal conductance, CO₂ consumed, internal carbon and electron transport rate), and morphological parameters (height and diameter), at 30, 60, 90 and 120 days after transplanting. At 120 days, the production of shoot, root and total dry biomass was evaluated. For macaúba, the application of biochar, at a dose of 2%, favored its photosynthesis. As for araçá, at 30 days after transplanting, the treatment without fertilization was better for most variables, however the treatments with biochar also had satisfactory results. The cajuzinho from the cerrado also responded positively to the application of biochar at all doses. The physiological and morphological variables responded well to treatments without fertilization and with application of biochar to the soil. Therefore, filter cake biochar can be indicated in the planting of the studied species, as well as the non-application of corrective and mineral fertilizer.