Effect of postharvest short-term radiation of near infrared light on transpiration of lettuce leaf

•NIR radiation suppressed transpiration of excised lettuce leaves and leaf lettuce.•Reduced transpiration extended shelf life.•NIR radiation with a wavelengths longer than 850nm affected transpiration rate.•Light with wavelengths shorter than 730nm did not affect transpiration rate.•Radiation of 5min induced stomatal closure and ROS accumulation in guard cells.