Produção de biomassa e atividade antioxidante de Campomanesia adamantium (Cambess.) O. Berg cultivada em substratos com resíduos orgânicos

Abstract

The objective of this study was to evaluate the effect of the use of different organic and bokashi residues composing substrates on growth, biomass production, phenol and flavonoid contents and antioxidant activity of Campomanesia adamantium (guavira) plants. The substrates were soil (without addition of organic residue), soil + chicken bed base rice husk, soil + base bed chicken bed, soil + castor bean meal and soil + Organosuper®, all with or without Bokashi use. The treatments were arranged in a 5x2 factorial scheme, in a randomized complete block design, with four replications. During the cultivation cycle the leaves were counted and the heights of the plants, collection diameter and SPAD index were measured. Plants were also harvested at 180, 240 and 270 DAT, for each treatment, in three seasons, to prepare the tea, which was used in the analyzes of phenol, flavonoid and antioxidant activity (DPPH). The plants were harvested whole at 270 DAT and separated in their respective organs, when the leaf and root areas were evaluated and the fresh and dry masses of the roots, stems and leaves. In general, the use of organic residues resulted in higher guavira plants (15.1 cm) and with greater number of leaves (that was 11.95 leaves / plant, at 210 DAT in plants grown on substrates with chicken bed base shell of rice). The plants that presented larger leaf areas and fresh and dry masses were used with rice husk base without bokashi, except when only soil was used. In general, the use of the chicken bed (base rice husk) without the addition of bokashi induced the increase of biomass production of guavira plant. Bokashi favored the development of the plant only when no organic residue was used. The levels of phenols, flavonoids and antioxidant activity were influenced by the use of the organic residues used in the cultivation substrate of guavira plants and, in the cultivation cycle, were higher in the leaves harvested at 240 days after transplantation.