Effects of nitrogen-phosphorus-potassium ratio fertilization on physiology and biomass accumulation of Erythropalum scandens Bl.

Erythropalum scandens Bl. is a common woody vegetable in South and Southwest China. Its tender stems and leaves are valued for their taste and high nutritional value. In this study, the “3414” fertilization method was used to carry out a top-dressing experiment on 1.5-year-old Daxin Provenance cutting seedlings of E. scandens to explore the effects of different nitrogen (N), phosphorus (P), and potassium (K) fertilization treatments on physiological characteristics and biomass accumulation. Compared to the control (CK), plant physiology and dry matter accumulation were improved under most fertilization treatments, and osmotic regulators and chlorophyll changed with fertilization. The main effect of N was stronger than that of P and K. In the late fertilization stage, both nutrient deficiency and over-fertilization showed mild nutrient stress. In addition, bulk element content in leaves in the late fertilization period was lower than that in the mid-fertilization period, which had a “nutrient dilution” effect. The optimal physiological and material accumulation conditions for the plant were urea 2.14 g/plant, calcium superphosphate 4.44 g/plant, and potassium chloride 0.67-1.33 g/plant. Overall, N played a prominent role in promoting and stressing E. scandens growth and development.