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

Document Type: Research Paper


1 PhD student of agronomy, Azad University of Gorgan, Iran

2 Faculty member of Shahrood University of Technology, Iran.

3 Faculty member of Azad University of Gorgan, Iran.


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