Deep tillage improves the rhizosphere environment in rainfed coffee cultivation on dense Cambisols through plant-soil interaction

Abstract

Deep tillage alleviates drought stress in dense soils through soil-root interactions, serving as a key adaptation to climate change. Enhancing soil structure for root growth and water retention, supported by geostatistical techniques, is crucial for informed decision-making in sustainable agriculture. This study evaluated the effects of deep tillage methods and chemical amendments on soil properties and coffee plant performance in Nazareno, Minas Gerais, Brazil, on a clay-loam Cambisol. A randomized complete block design with split-plot arrangement was used, including three blocks, six depths (0–0.05, 0.15–0.20, 0.35–0.40, 0.55–0.60, 0.60–0.70, and 0.75–0.80 m), and five treatments: SP40 (furrower at 0.40 m), SP60 (Big Mix at 0.60 m, with liming as SP60AL), and SP80 (soil homogenizer at 0.60 m, subsoiler at 0.80 m, with liming as SP80AL). After five years, undisturbed soil samples were collected at different depths in the experimental area and an adjacent site under native Cerrado vegetation. In trenches, soil penetration resistance (PR), root growth, and chemical element contents were analyzed. Soil moisture was assessed using a probe from October 2019 to March 2021. ANOVA, Scott-Knott, and Dunnett tests (p < 0.05) were used for data analysis. Geostatistical kriging mapped PR, root variables, element contents, and soil moisture. SP60 improved soil structure, root growth, and water uptake, enhancing antioxidant activity under drought. SP80AL enhanced water retention and root development up to 0.70 m but had lower drought tolerance. Geostatistical mapping was crucial for understanding deep tillage impacts on rhizosphere management, aiding sustainable coffee cultivation.