Alleviation of drought stress effects on red bean by ultrasonication and foliar application of 24-epi-brassinolid

Abstract

<span class="fontstyle0">The two-location field experiment was conducted to study the possible alleviation of drought<br />stress effects on red bean by ultrasonication and 24-epi-brassinolid. Locations were Agricultural<br />Research Center in Shahrood, Iran and the other in bean farm, 40 km off Shahrood city in 2015.<br />Experiment factors included irrigation of main plots at three levels of normal irrigation (60 mm<br />evaporation from evaporation pan), mild stress (90 mm evaporation from evaporation pan) and<br />severe stress (120 mm evaporation from evaporation pan). Stress levels were applied after 4-leaf<br />stage and ultrasound waves treatments (in two levels of nonuse of seeds irradiation and use of<br />irradiation for 3 minutes at 32 °C) and 24-epi- brassinolid foliar application (in two levels of<br />nonuse of foliar application and foliar application at a rate of 0.1 mg/L at 50% flowering during<br />two stages) which were located in sub-plots. The evaluated properties included grain yield and<br />contents of superoxide dismutase, peroxidase, catalase, proline and ascorbate. The results<br />showed that with severe water stress (comparison of severe stress and lack of stress), grain yield<br />showed a significant decrease in both experiment sites, however 24-epi-brassinolid foliar<br />application and use of ultrasonic waves in both normal and stress conditions increased the grain<br />yield. The same condition was established for evaluated enzymes. Thus it could be stated that<br />irradiation of ultrasonic waves and 24-epi-brassinolid foliar application for cultivating beans<br />play important role in increment of competitive strength of plant in water deficit condition.</span>