Biorreguladores na mitigação do estresse hidrico e no perfil de óleos essenciais em coentro-maranhão

Abstract

Aiming to evaluate the action of bioregulators on the morphophysiology and profile of essential oils in Eryngium foetidum plants, four experiments were conducted. In the first, two concentrations of carnitine were applied in culantro plants (100 µM and 10 mM), and after 72 days, analyzes of growth, photosynthetic content, gas exchange parameters and chlorophyll a fluorescence were measured. In the second experiment, 100 µM of carnitine was applied in culantro plants under different water conditions: well-watered, drought and re-watered. In the third experiment, 100 µM of ascorbic acid was applied in culantro plants under drought. In the fourth experiment, 100 µM of salicylic acid was applied in the plants, also in different water conditions (well-watered, drought and re-watered). After 100 days, morphological, physiological and essential oil profile analyzes were performed. 100 µM of carnitine increased growth of culantro plants under non-stressful conditions and 10 mM did not alter growth. Water conditions and application 100 µM of carnitine changed the essential oil profile of the culantro plants. Eryngial production was increased in drought as well as in re-watered with the application of carnitine, and hydroquinone was produced only in the combination of re-watering and carnitine. Ascorbic acid, under non-stress conditions, restored pigment concentration, and drought conditions, it modulated qualitatively the essential oil profile, with dodecenal being the compound that most contributed to this profile separation. Salicylic acid application did not mitigate the effects of drought, but under well-irrigated and re-irrigated conditions increased leaf area and photosynthetic pigments. Furthermore, the exogenous application of salicylic acid in drought modulated the profile of essential oils. These results in culantro can serve as a basis for other studies about use the bioregulators carnitine, ascorbic acid and salicylic acid in culantro plants, in addition to providing information on the relation between different water conditions and bioregulators, providing new perspectives to explore production the compounds of industrial and economic interest.