عنوان مقاله [English]
Acacia with the scientific name Acacia salicina is a tree or shrub from the leguminous family and a nitrogen fixer. This species is native to dry areas in southern Australia. In some areas, this species is used as a source of fodder for livestock, for ornamental purposes, and for revival areas without vegetation. Climate change is one of the most important concerns of the world's growing population. Drought is one of the most important abiotic stresses that affects the nutritional status of plants. Stresses constantly affect the growth and development of plants, which are considered the most important factors of yield reduction in the world. Stresses are the result of abnormal physiological processes that are caused by one or a combination of biological and environmental factors, and drought is one of the most important abiotic stresses that affect growth and performance, as well as this Stress can cause plant death and limits approximately 25% of agricultural production. One of the most common ways to withstand drought stress is the use of super absorbent polymers. Commercial superabsorbent polymers are hygroscopic materials similar to sugar, and the shape of these polymers must be maintained after absorbing water and swelling. They don't have harm for soil, plants and environment. Considering the increase in temperature and pollution the purpose of this research is the effect of using three types of super absorbent polymers to increase N.P.K. absorption, water retention, reduce irrigation, reduce costs and improve the growth of acacia plants under drought stress conditions for cultivation in areas free of vegetation in Khuzestan to contrast with fine dust. In order to improve the nutritional status of acacia, a research was conducted using three types of superabsorbent polymers in three concentrations at three levels of drought stress in a factorial format in a completely randomized block design with three replications in the agricultural faculty of Shahid Chamran University of Ahvaz. The results showed that the use of superabsorbent polymers significantly increases the amount of nitrogen, potassium and phosphorus absorption by leaves, stems and roots. The concentration of 2 g/kg of A200 hydrogel in the first week increased leaf nitrogen by 12.85%, leaf phosphorus by 17.64%, stem nitrogen by 50.29% and root nitrogen by 4.96%. In the first week, SNF superabsorbent had the highest amount of potassium in stem and phosphorus in the root. Among the hydrogels, SNF superabsorbent polymer had the highest amount of phosphorus in the stem in the second week and a concentration of 1 g/kg, and this increase was significant compared to some treatments, and the lowest amount of phosphorus in the stem were obtained s in the treatment of the first week and a concentration of 0 g/kg Super absorbent polymer A200 and SNF. Increasing the concentration of super absorbent polymers increased the amount of phosphorus in the stem in most cases. increase in the intensity of drought stress caused a decrease in the amount of leaf nitrogen compared to non-stressed conditions, so that the lowest amount of nitrogen was obtained in the third week of treatment with SNF superabsorbent polymer at a concentration of 0 g/kg, which caused a decrease of 29.04% compared to the control. The increase in the severity of drought stress caused a decrease in the amount of phosphorus in leaves compared to the first week, so that the lowest amount of phosphorus was obtained in the second week in the concentration of 2 g/kg of SNF,which had a decrease of 52.94% compared to the control. intensity of drought stress and increasing the frequency of irrigation caused a decrease in the amount of nitrogen in the stem, so that the lowest amount of nitrogen was obtained in the third week and the concentration of 0 g/kg of Barbari hydrogel, which was a 32.16% decrease compared to the control. The lowest amount of root phosphorus was obtained in the third week of treatment with a concentration of 2 grams per kilogram of Barbarii superabsorbent polymer, which caused a decrease of 54.54% compared to the control. Based on the results of this research, the use of A200 superabsorbent polymer compared to other hydrogels had the greatest effect on the nutritional status of the plant and the absorption of N.P.K elements.