The Effect of superabsorbent polymer application on some biochemical traits and relative water content of bean cultivars under drought tension

In order to investigate the effect of superabsorbent polymers use on some biochemical traits and relative water content of bean cultivars under drought tension conditions, an experiment was carried out as split-split plots design based on randomized complete blocks design with three replications in Kaleybar city in 2015 cropping year. The main factor included irrigation after 70, 140 and 210 millimeter water evaporation from class A evaporation pan, bean cultivars (red beans, cowpea , pinto bean and white beans) as sub plots and four levels of 50, 100, 150 and 200 kilogram per hectare superabsorbent application as sub-sub factor. The obtained results of analysis of variance showed that the interaction of drought tension and superabsorbent on the activity of superoxide dismutase enzymes, glutathione peroxidase, chlorophyll a, total chlorophyll and proline concentration was significant. The results of the comparison of the mean interactions of drought tension and superabsorbent showed that maximum activity of antioxidants enzymes and proline obtained by treatment 50 kilogram per hectare super absorbent application at drought tension level of 210 millimeter evaporation. The results showed that with increasing drought tension, the activity of antioxidant enzymes increased and chlorophyll a, chlorophyll b, total chlorophyll, carotenoids and relative content of water decreased. In four assessed cultivars, cowpea had the most frequent photosynthetic pigments, the relative water content of leaf, proline content of leaf and the highest activity of antioxidant enzymes. According to the results, superabsorbent has reduced damages caused by dry land.