The effect of zinc sulfate and gibberellic acid on gas exchange and white bean (Phaseolus vulgaris)performance under drought stress

Drought stress is one of the main factors in reducing the usefulness of various plants, especially legumes, so it is necessary to use methods that can reduce the effects of stress on the plant. In order to investigate the effect of zinc and gibberellin on the biochemical and physiological characteristics of white beans (Phaseolus vulgaris L.) in drought stress conditions, an experiment in the form of double-plotted plot with a randomized complete block with three replications in two locations (Islamabad West Research Station). Kermanshah province, and Khorramabad research station in Lorestan province. Experimental factors include irrigation at 3 levels of 60, 90 and 120 mm evaporation from Class A evaporation pan as the main plot, zinc sulfate solution at 4 levels 0, 1.5, 3.5 and 4.5 ml/liter and 2 levels Gibberellin spraying and spraying were used as sub-plots. Data analysis and comparison of average data by Duncan's method was performed at 5% level by SPSS software. The results showed that the main effect of drought stress and zinc sulfate foliar application was significant on all traits, and the main effect of gibberellin foliar application on all traits was significant except for yield and transpiration rate. The interaction of zinc sulfate, stress and gibberellin had all significant properties. The highest grain yield was related to normal irrigation treatment and consumption of 4.5 ‌ml/l of zinc at, which differed from the treatment of moderate stress and consumption of 1.5 ‌ ml/l of zinc and the use of gibberellin. It did not make much sense. The lowest grain yield in the severe stress treatment and the use of 3.5 milliliters per liter on the gibberellin spray solution. In general, seed yield increased both in drought stress and non-stress conditions, so according to the results, it is recommended to consume 4.5  ml/l of zinc sulfate and Gibberellin foliar application to reduce the effects of drought stress on bean cultivation.