Indução de tolerância à salinidade e restrição hídrica em sementes de algodão por meio de moléculas sinalizadoras

Abstract

Abiotic stresses are the main cause of crops productivity loss. These stresses compromises growing, development, and plant survival, as in seed germination. Under those conditions, studies have been carried regarding production of reactive oxygen species which results in cell membrane damage and antioxidant-related gene expression. Thus, this study aimed to evaluate physiological condition efficiency on cotton seeds (Gossypium hirsutum) in the presence of signalizing molecules to induces salinity and hydric deficiency tolerance during seed germination and seedling development. We evaluated physiological and biochemical aspects regarding different types of abiotic stresses, physiological conditioning, and signalizing molecules usage. Were used the signalizing molecules melatonin, indoleacetic acid, nitric oxide, hydrogen peroxide, and chitosan and two conditions of abiotic stress (salinity and hydric restriction). Were evaluated water content, seed germination, and vigor. Also, through image analysis, seedling development was evaluated. Biochemical aspects of proline content, lipidic peroxidation, and activity of antioxidant enzymes on seeds and seedlings was evaluated through the treatments. Experiments were established on completely random design with eight replicates. We observed the benefits of physiological conditioning and usage of signalizing molecules, which resulted on increase of salinity and water restriction during cotton seed germination and seedling development. Also, through this research, was possible to observe the physiological and biochemical aspects involved in the physiological conditioning and signalizing molecules related to salt and water stresses.