Efeitos do peróxido de hidrogênio (H2O2) na morfologia e bioquímica de plantas de Lippia grata Schauer submetidas a restrições hídricas

Abstract

Lippia grata belongs to the Verbenaceae family, is native to Brazil found in the phytogeographic domains of the Cerrado and Caatinga, Atlantic Forest and Amazon. It is popularly known as alecrim-da-chapada and alecrim-do-mato, which is widely used as a medicinal product, due to the essential oil present in its leaf trichomes, which have bioactives with antiseptic, antimicrobial, antifungal and antibacterial properties. Because it is located in semi-arid environments, water becomes the main limiting factor for the species, and therefore strategies to mitigate the harmful effects of water deficit have been used, such as the application of signaling molecules (elictors), such as hydrogen peroxide, in order to assist plants in conditions of intensified drought stresses. Taking into account the importance of L. grata and its essential oils, since water deficit can affect its development, the objective of the following study was to evaluate the influence of hydrogen peroxide on the biometric and biochemical parameters in L grata subjected to restriction water For this, the leaves of L. grata plants were sprayed with H2O2 at concentrations of 0μM (control), 0.675μM L-1 and 1.35μM L-1 and then subjected to three irrigation regimes: 25%, 50% and 75% of vessel capacity for 60 days. Where biometric parameters and some osmoregulators were measured. The water restriction allied to the higher concentration of hydrogen peroxide (1.35μM L-1) negatively affected the growth and development of L. grata plants, being expressed in the biometric parameters (impairment of growth and production of branches), dry mass of shoots and increase in proline levels.