Physiological severe iron deficiency yellowing, spoon-shaped parietal lobe is an occasional manifestation of calcium deficiency. It is suggested that mineral humic acid water-soluble fertilizer Tianci Yigen+chelated iron fertilizer should be used for irrigation in the near future, and calcium and magnesium nitrate can be used for irrigation in conditional plots, or sugar alcohol calcium and magnesium fertilizers can be sprayed on the leaves in the state of 1 0,000 times of Tianci calcium and magnesium+3,000 times of trace elements, with an interval of 7- 1.