Management period of rootstock at seedling stage

The rootstock grows slowly in the seedling stage and is not tolerant to drought. When the water content in the 0 to 20 cm soil layer is less than 12%, it needs irrigation to replenish soil moisture. When the seedling is 15 cm high, apply topdressing once. When the seedling height is 30 cm, the second topdressing is applied. When topdressing, dig a trench with a depth of 4 to 5 centimeters on one side of the seedling line, and apply fertilizer. Apply 20 kg of diammonium phosphate or the same amount of other chemical fertilizer per mu each time.