Evaluation of methods of application of H2O2 for salt acclimation of sunflower plants

Abstract

The objective of this study was to evaluate the effect of different methods of application of hydrogen peroxide (H₂O₂) via seed and/or via foliar in sunflower (Helianthus annuus L.) plants under salt stress. The experiment was conducted in a greenhouse, in the experimental area of the Núcleo de Engenharia de Água e Solo - UFRB. Five treatments were tested: control (absence of NaCl); salt control (presence of 100 mM NaCl); 1 mM H₂O₂ via seed (in presence of 100 mM NaCl); 1 mM H₂O₂ via foliar (in presence of 100 mM NaCl); 1 mM H₂O₂ via seed + 1 mM H₂O₂ via foliar (in presence of 100 mM NaCl). The assay was conducted in a completely randomized design with 4 replicates. The plants were maintained during a period of 20 days in a floating type hydroponic system. Salt stress affected negatively the production of leaves, stem, roots and total dry mass. Pretreatment with H₂O₂ application via seed and the combination via seed + foliar via were able to reduce the deleterious effects of salinity, providing higher relative biomass yields.