Papers Proceedings »
Evaluation of water stress in Pinus devoniana Lindl., in preconditioning stage in nursery under the application of silicon
The plants tolerate drought in the plantation site when they are subjected to a preconditioning in a nursery using water stress. The aim of this research was to evaluate the effect of silicon and water stress on Pinus devonian in nursery stage. Four-month-old plants were subjected to silicon applications (powder or liquid) at 100 and 300 ppm. Water stress consisted of continuous irrigation and restricted irrigation. The experiment consisted of a 22 factorial design with 4 replicates. The variables height, diameter, fresh and dry weight of foliage and root, aerial volume and root were evaluated. Dickson quality index, robustness index, lignification index, shoot/root ratio and root container index were evaluated as plant quality parameters. The mineral content (macro and micronutrients), silicon concentration leaves and roots were also evaluated; as well as the percentage of survival in the field after six months. Plants with unrestricted watering were favored in the plant quality. All plants showed water stress, it was found that the recovery point was the third day of watering and wilting point was the seventh day. Macronutrients content was not affected by applying silicon and water stress; while silicon applications without water stress the micronutrient content in the leaves was increased. High concentrations of silicon were obtained in the leaves by applying to the substrate 100 and 300 ppm, or 300 ppm via foliar, in addition, the plants showed better morphological and physiological development. Adding 100 and 300 ppm of silicon to the substrate or 100 ppm via foliar, higher mycorrhization and survival percentage were obtained, even under stress conditions. After six months of transplantation in the field, plants without water stress treated with 100 ppm of silicon to the substrate exhibited 84% survival, indicating that silicon promotes an increase in the survival of plants at the plantation site.