Effects of Fertilization with Different Proportion of Nitrogen, Phosphorus and Potassium on Physiology Growth of Picea likiangensis Seedlings

Taking the three-year high-quality seedlings of Picea likiangensis as the research object, the orthogonal design of 3 factors and 3 levels was used to treat seedlings with 9 different fertilization treatments with different ratios of nitrogen, phosphorus and potassium through pot experiments to analyze the effects on the growth and photosynthetic physiology of P. likiangensis seedlings. The results showed that different proportion of nitrogen, phosphorus and potassium had certain promotional effects on the seedling height, crown width, chlorophyll content and photosynthetic characteristics of P. likiangensis seedlings, but there were differences among treatment groups. The T₇ fertilization ratio (urea 5 g/plant, calcium superphosphate 7 g/plant, potassium sulfate 2.5 g/plant) had the most obvious promotional effect on the crown width, chlorophyll content, net photosynthetic rate, stomatal conductance, transpiration rate and light compensation point of P. likiangensis, which was significantly higher than that of the control. In general, T₇ fertilization was the most beneficial to the growth and promotion of photosynthetic capacity of P. likiangensis seedlings among different fertilization groups.