Hydrogel is used as water absorbent in soil. The super absorbent can absorb water about 400 times of its weitgh and can deliver about 95% to a plant. In this study the effect of various amount of hydrogel on growth characteristics of an Acacia (Robinia pseudoacacia), Pine (Pinus eldarica) and Bunge (Haloxylon Persicum) was experimented. The experiment was a factorial one with completcly randomized design which lasted for 3 years from 2006 to 2009.
Hydrogel application significantly incaresed freshness percent, hight and canopy diameter in bunge, however increasing additions at hydrogel decreased these 3 characterestis in acacia and pine during 3 years of experiment. It should be mentioned that during experiment time freshness percent in Pine was significantly higher than two other spicies. While increasing hydrojel additions did not cause any change in Acacia’s stem diameter, it incrased stem diameter in Bunge and decreased stem diameter in Pine. Application of two hydrogel concentrations on Bunge plant did not have any significant effect on canopy diameter.
Survival of Acacia and Pine decreased by increase of hydrojel in soil. Although increasing hydrojel in soil lead to increase in survival in Bunge plant. During 3 years at experiment, survival percentage of Acacia was significantly more than two other species. Treatment with 100gr hydrogel increased Pine survival significantly in comparesion to 50gr hydrogel treatment. According to the findings, it seemed that Acasia has the highest percentage of survival, hight, stem and capony diameter in Semnan’ climate.
Although freshness is not too high, but percentage of dead plants (18.5%) is less than Pine and Bungue. Increasing hydrojel lead to increase in freshness, hight, stem and capony diameter and survival in Bungue plant. Therefore the findings showed that Acasia is the most appropriate plant for planting in Semnan district, and if hydrojel is used. Bunge pland would be more appropriate than other two spiecies.