Respuesta in vitro al estrés salino en caña de azúcar esta condicionada por la concentración y condición de exposición al NaCI

Abstract

Salinity is one of the major environmental stress factors that affect crop productivity, as well as interfering with plant growth and development, resulting in reduced production quality. Given this, we highlight the importance of research in response to plants subjected to salt stress in order to assess the physiological and biochemical behavior of genotypes, with the objective of selecting the more tolerant. One way to ensure the uniformity of the response of the plants is through in vitro cultivation, which allows control of the cultivation conditions. Therefore, the objective of this work was to evaluate the response of two commercial varieties of sugar cane exposed to saline stress in different conditions (gradual and abrupt). Two varieties of sugarcane (RB931011 and RB872552) were subjected to in vitro salt stress by NaCl (56 mM and 112 mM), either gradually or suddenly. The responses of the enzymatic antioxidant system (catalase, peroxidases and ascorbate peroxidase) and free proline, as well as the Na+ and K+ contents, were assessed 30 days after the beginning of the treatments. Differences were observed in the responses of the varieties as a function of the induction mode of salt stress, graded or by shock, rather than as a function of the NaCl concentrations in the culture medium. The stress response is therefore conditioned not only by salt concentration, but also by the form of exposure to salt.