J. M. Nunes, L.O.O. Bertodo, Luana Morais da Rosa
Sep 1, 2014
Citations
0
Influential Citations
28
Citations
Journal
South African Journal of Botany
Abstract
Abstract Uliginosin B, an antidepressant-like phloroglucinol derivative, three benzopyrans and total phenolic compounds (TPC) of flowering Hypericum polyanthemum acclimatized plants were quantitatively analyzed in response to stress factors. Drought stress alone or combined with mild fertilization; continuous salicylic acid (SA) application alone or combined with mild fertilization and time course effects of mechanical damage and SA exposure alone and combined were analyzed. Drought stress did not affect final plant biomass, promoted significant increase of uliginosin B (40-fold in the leaves and 6-fold in the reproductive parts), HP1, HP3 and TPC, whereas the stress applied on mild fertilized plants increased biomass and uliginosin B (7.5-fold and 1.5-fold in the leaves and reproductive parts, respectively) and HP3 (4.4-fold in the leaves) concentrations, unaffecting TPC. Continuous application of 2 mM SA alone or combined with mild fertilization resulted in similar increase of uliginosin B and TPC. Time course experiments of mechanical damage with and without SA (10 mM) as well as the treatment with SA induced the biosynthesis of uliginosin B in the leaves, with higher levels verified in wounded plants after 2 days (5-fold) and 7 days (3-folds) of treatment, reducing or not affecting benzopyrans accumulation. The compiled results suggest that a substantial increase of the most important pharmacological active compounds uliginosin B and HP1, associated with higher plant biomass yield can be achieved by modulating drought stress response in fertilized plants.