PADRÃO DE ACÚMULO DE ALUMINIO E SUA RELAÇÃO COM A MORFOMETRIA E ACÚMULO DE FÓSFORO EM BYRSONIMA BASILOBA E BYRSONIMA LAXIFLORA EM ESTAÇÕES SECA E CHUVOSA

Abstract

The Cerrado hosts a remarkable diversity of fauna and flora, with many endemic species, turning it one of the world’s primary biodiversity hotspots. Its soil, characterized by low nutrient levels and high aluminum (Al) content, typically has a pH below five. Some Cerrado species are adapted to these conditions and can accumulate Al in their tissues without showing toxicity symptoms. The objective of this study was to determine the pattern of Al accumulation and distribution in aerial vegetative organs and examine its relationship with morphometry and phosphorus (P) uptake in Byrsonima basiloba and B. laxiflora. This was evaluated by determining the AI and P concentration range and preferential accumulation sites. Byrsonima plant materials were collected in Rio Verde, Goiás, across two seasons: from October to December 2022 (rainy season - summer) and from July to August 2023 (dry season - winter). Soil granulometric and chemical analyses were conducted, with samples taken from 10 subsamples at two depths (0-20 and 20-40 cm). The collected plant materials (stems, mature leaves, and young leaves) were dried, ground, and digested in a 1N HCl solution. Following digestion, Al and P levels were quantified by spectrophotometry, using a colorimetric method with eriochrome cyanine R (for Al) and a spectrophotometric method with molybdenum blue (for P). The species B. basiloba and B. laxiflora can be categorized into two eco physiologically distinct groups based on Al and P concentrations in their stems, and mature and young leaves. No correlation was found between these elements' concentrations in either species. In the summer, B. basiloba exhibited higher Al and P concentrations than B. laxiflora in all plant parts. In the winter, Al concentrations in stems, mature leaves, and young leaves were similar between the two species; however, while P concentrations in stems did not differ, B. laxiflora had higher P concentrations in mature and young leaves.