BIOCHEMICAL RESPONSE AND BIOMASS PRODUCTION OF RHIZOPHORA MANGLE L. TO EXPOSURE TO 2,4- DICHLOROPHENOXYACETIC ACID, UNDER EXPERIMENTAL CONDITIONS

Anthropogenic activities have led to the degradation of mangrove ecosystems worldwide.The impact of herbicides reduces the survival of seedlings.Herbicides reduce the survival of seedlings by modifying the interstitial water's hydrological, soil, and physicochemical conditions, thus representing a latent risk in the environmental services these ecosystems provide.In this research, the behavior of biochemical parameters (total nitrogen, total protein, flavonoids), chlorophyll a, lipids, and the phytotoxic effect on the production of total biomass in Rhizophora mangle seedlings exposed to concentrations of 5 w/v dilutions (0%, 5%, 10%, 25%, 50% and 100%) of 2,4-Dichlorophenoxyacetic acid (2,4-D) in propagules grown in greenhouses was evaluated.Three phases were monitored: (1) stabilization of the water recirculation system, homogenization of interstitial water and adjustment of the artificial tide; (2) afforestation and conditioning;(3) application of 2,4-D acid, and monitoring of the concentration of biochemical parameters, chlorophyll a, lipids, total biomass and physicochemical parameters of interstitial water.The results showed that increasing the concentrations of 2,4-D generates a decrease in the concentrations of the biochemical variables, chlorophyll a, total biomass, and an increase in the concentration of fat in the seedlings, where variations were observed showing significant differences (p < 0.05).An inverse relationship was presented between the biochemical variables in chlorophyll a, total biomass production, and fat concentration.The research showed that Rhizophora mangle seedlings are very vulnerable to different concentrations of 2,4-D and to the developmental conditions to which they were exposed in this research.