Effects of transplantation and potassium fertilizer on the photosynthetic characteristics and chlorophyll content of Dalbergia odorifera

Dalbergia odorifera T. Chen was used to analyze the effects of transplantation and potassium fertilizer on its photosynthetic characteristics and chlorophyll content. Results showed that the maximum net photosynthetic rate of plants after root pruning was 19.25%, 34.79%, 40.88%, and 219.86% higher than that of de-crowning, full-crown transplantation, CK, and de-crown transplantation. The maximum light saturation point(LSP) occurred under de-crowning treatment, and the maximum light compensation point(LCP) occurred under root pruning. The net photosynthetic rate(P_n) and transpiration rate(T_r) were highest under root pruning treatment. Compared with CK, the contents of Chla, Chlb, Chl(a + b), and Car were all higher under root pruning, de-crowning, and full-crown transplantation. Chla, Chlb, and Chl(a + b) all increased with the increase in potash fertilizer. The maximum net photosynthetic rate increased with the increase in potassium fertilizer dosage. The LSP value was largest under K₂ treatment. As the amount of potash fertilizer increased, P_n and Cond showed a tendency to increase. The Chla/Chlb ratio under CK treatment was significantly higher than that under K₁ and K₂. Root pruning, de-crowning, and applying potash fertilizer significantly increased the chlorophyll content of D. odorifera, which was beneficial for photosynthesis and the promotion of plant growth.