Cucumber leaves will shrink and recover later. What's going on here?

Because of the low temperature, less light and high humidity, it is necessary to spray natural brassinolide on leaves in time, and spray humic acid active liquid fertilizer plus potassium dihydrogen phosphate plus triacontanol every 7~ 10 days, or compound nitrophenol sodium plus amino acid active liquid fertilizer plus Xingpeng phosphorus and potassium 1 Galida light fertilizer to speed up the recovery of normal growth.