Ação reguladora de eliciadores nas características bioquímicas, ecofisiológicas, anatômicas e na produção e qualidade de óleo essencial de Piper mollicomum Kunth

Abstract

The objective of this study was to evaluate the effectiveness of chitosan and elicitor methyl jasmonate on phenolic and antioxidant metabolism, gas exchange and leaf anatomy of Piper mollicomum, in order to adapt the production system to increase biomass production and quality essential oil. The solutions of chitosan in concentrations of 2.5%, 5% and 10% and methyl jasmonate 0.5, 2 and 8 mM, were sprayed on all leaves of the plants after seven months of cropping. Were used as control plants without spraying and sprayed with solvent only, with 0.05N HCl with pH adjusted to 5.5 to chitosan and 0.1% Tween 20, for methyl jasmonate. Chitosan and methyl jasmonate were effective in promoting the antioxidant activity and phenolics in developing leaves and fully expanded. The chitosan reduced gas exchange, the leaves being more susceptible to developing this application elicitor. The application of methyl jasmonate 0.5 mM photosynthetic efficiency and increased efficiency instantaneous water use, regardless of the stage of leaf development. Both elicitors promoted biomass accumulation in roots and did not affect the growth of the shoot. Chitosan caused a 10% change in the cell which can be classified as a result of development of programmed cell death. The application of methyl jasmonate induces structural changes that may be advantages in plant-pathogen or plant-herbivore. The application of chitosan reduced the 10% essential oil content of leaves and roots of Piper mollicomum, while the lowest concentration did not alter the content in the leaves, but increased in roots. The application of the 5% chitosan and methyl jasmonate 0.5 mM are effective in producing essential oil, especially considering dilapiol in the production of roots.