Association of edaphoclimatic characteristics and variability of condensed tannin content in species from Caatinga

Resumo

Condensed tannin (CT) concentrations in plants are influenced by species, plant part, season, growth phase,
environmental conditions, disease and defoliation. The objectives of this study were to determine the effects of edaphoclimatic
factors on the concentration of CT stored in leaves and bark from Mimosa tenuiflora (Wild.) Poiret and Anadenanthera
macrocarpa (Benth.) Brenan., collected at three distinct locations in northeastern Brazil. At each study site, sampling was
carried out by randomly selecting five trees, each tree represented one replication and samples of leaves and bark of each
plant species was collected. Soil samples were collected near the base of each plant for moisture, physical and chemical
analysis. Meteorological data from each month and site were obtained of the INMET automatic station. We conducted a
principal components analysis using a multivariate technique to observe the influence of soil and weather on condensed tannin
concentration. Overall, Anadenanthera macrocarpa has the least total CT concentration in both plant fraction and site. Our
results suggest that soil chemical characteristics, soil moisture and weather explain 76.27% and 75.92% of the variation in CT
produced by Mimosa tenuiflora and Anadenanthera macrocarpa, respectively. Condensed tannin concentration in these two
species is negatively associated with soil moisture and rainfall, and positively associated with temperature and soil chemical
elements.