Elicitação com quitosana no crescimento e nos compostos voláteis de Mentha arvensis in vitro

Abstract

Elicitors are substances with the ability to induce the production of specific secondary metabolites. The objective of this study was to evaluate the effect of chitosan on growth, photosynthetic pigment production and volatile compounds of Mentha arvensis on culture medium. Nodal segments of M. arvensis were inoculated in MS medium supplemented with five chitosan concentrations (0, 50, 100, 150 and 200 mg L-1 ). After 30 days of cultivation, shoot length, leaf, shoot, root and total biomass were evaluated. In addition, analyzes of volatile compounds and photosynthetic pigments were investigated. The addition of chitosan in 100 mg L-1 promoted greater accumulation of dry biomass in all evaluated organs. On the other hand, high concentrations (150 e 200 mg L-1 ) showed phytotoxic effect on plantlets. Higher levels of chlorophyll a and carotenoids were observed without chitosan and chlorophyll b supplementation with 200 mg L-1 . Chitosan influenced the concentration of volatile constituents in vitro. At the lowest concentration of chitosan (50 mg L -1 ) there was greater accumulation of pulegone, 100 mg L-1 limonene and 200 mg L-1 menthol and mentone.