Ecofisiologia de Arecaceae em Ambiente Indígena

Abstract

In the context of the vast biodiversity of the Amazon biome, the botanical family Arecaceae stands out with significant socio-economic value for local communities. Despite its remarkable economic and ecological relevance, placing it among the most important in the world, there is still a lack of comprehensive studies on its physiological characteristics, such as chlorophyll content and the composition of secondary metabolites, such as leaf polyphenols in the flavonoid class, which include subclasses of flavonols and anthocyanins. The present study aimed to characterize the indices of four eco-physiological parameters, namely: Nitrogen Balance Index, Total Chlorophyll Index, Flavonoid Index, and Anthocyanin Index in the leaves of four palm species located in the Munduruku Indigenous Territory of Planalto, in Santarém, Pará. This territory covers floodplain and upland areas, accessible via PA-370 Highway, and borders with other communities, quilombos, and settlements. Four Arecaceae species of socio-economic importance and bioeconomic potential were selected and identified: Attalea speciosa Mart. ex Spreng (babaçu), Oenocarpus bacaba Mart. (bacaba), Bactris gasipaes Kunth. (pupunha), and Astrocaryum aculeatum G. Mey. (tucumã). Measurements were taken in november 2022, between 8 AM and 12 PM, on three individuals of each species, totaling 12 palm trees. Two measurements were taken on each selected individual, on the abaxial and adaxial sides of the leaves, using the DUALEX® Force A chlorophyll meter. The measured data were analyzed using BioEstat® software version 5.3, through Descriptive Statistics and Analysis of Variance (ANOVA) with one criterion for the four species, ANOVA with two criteria to compare the adaxial and abaxial sides of the leaves, as well as multivariate analyses, including the calculation of Bartlett, Penrose, and Mahalanobis coefficients, and Pearson's correlation matrix. The results obtained allowed inferring that there are significant differences in the constitution of eco-physiological parameters among the species. Regarding the Nitrogen Balance Index (Nbi), the B. gasipaes species stood out with the highest index on both sides of the leaves. On the other hand, the palm A. aculeatum demonstrated higher photosynthetic efficiency, indicated by the higher Total Chlorophyll Index (Chl). Concerning polyphenols, flavonols, and anthocyanins, the palms A. aculeatum and O. bacaba presented the highest leaf levels. No significant differences were observed among the studied parameters when considering the leaf sides.