Effects of zinc fertilizer on yields and quality of Fructus aurantii

Abstract: 【Objective】Most studies on Fructus aurantii focused on the activity of pharmacoactive ingredients, pharmacological effects, processing methods and cultivation techniques, but few are related to yield and quality. Exploring the influence of zinc fertilizer on the yield and quality of F. aurantii could promote the industry development of F. aurantii.【Methods】Using F. aurantii‘Xinxiang’planted more than five years ago as the experimental materials, two treatments were designed in Xingan and Zhangshu experimental field. With the conventional fertilization as the control (CF), the other treatment was set as spraying with 0.3% zinc sulfate solution on the leaf surface at both the young fruit stage and fruit swell stage. At maturity stage, yields and yield components, nutrient content, pharmacoactive component contents and accumulations of zinc in F. aurantii were analyzed.【Results】After zinc fertilization application, the yield, naringin and neohesperidin contents per plant and total zinc accumulation per plant of F. aurantii significantly increased. In the Xingan experimental field, the yield of F. aurantii was 4143 kg · hm^-2 , which was 22.23% higher than CF. The amounts of naringin and neohesperidin perplant in Xingan were 142.5 g and 97.2 g, respectively, which were 51.3% and 55.6% higher than CF. The amount of total zinc per plant in Xingan was 28.0 mg, which was 61.2% higher than CF. In Zhangshu experimental field, after zinc application, the yield of F. aurantii was 2959 kg · hm^{- 2} , which was 64.9% higher than CF. The amounts of naringin and neohesperidin contents per plant in Zhangshu were 66.5 g and 44.5 g, respectively, which were 68.8% and 51.9% higher than CF. The amount of total zinc per plant in Zhangshu was 7.89 mg, which was 71.4% higher than CF. There were significant differences in yield components and the amount of pharmacodynamic components per fruit between zinc fertilization treatment and CF in different production areas. After zinc fertilization application, the fresh weight of single fruit in the Xingan significantly increased. The fresh weight of single fruit reached 69.2 g per fruit, which was an increase of 15.3% compared to CF. The number of fruits in the Zhangshu increased to 45 per plant, which was 55.2% higher than CF. There was no significant difference in the amount of pharmacodynamic components per fruit in Zhangshu between the two treatments. The amount of naringenin and neohesperidin contents per fruit in the Xingan significantly increased, which were 1.2 g and 0.8 g, and 37.6% and 41.4% higher than those of the control, respectively. This may due to the enhancement of the accumulation of pharmacodynamic components in F. aurantii after the application of zinc fertilizer, and then naringin and neohesperidin were evenly distributed in each fruit. Besides, there was no significant change in the number of fruits per plant in the Xingan, and the number of fruit per plant in Zhangshu increased significantly, so there was no significant difference in the contents of naringin and neohesperidin compared with the control in Zhangshu, but the cumulative amount per plant increased significantly. After the application of zinc fertilizer, the moisture content of F. aurantii decreased and the dry matter content increased. The water content of F. aurantii in Xingan and Zhangshu experimental fields decreased by 29.7% and 6.3%, and the dry matter contents increased by 31.2% and 7.8%, respectively. In addition, the accumulation of total zinc per plant was significantly and positively correlated with yield, yield components and the pharmacodynamic components per plant. While the accumulation of total zinc per plant increased significantly, the yield, the accumulation of naringin and neohesperidin per plant also increased significantly.【Conclusion】Compared with the conventional fertilization, the application of zinc fertilizer at both the young fruit stage and fruit swell stage can significantly improve the yield and quality of F. aurantii. The accumulation of pharmacodynamic components and total zinc content per plant can significantly increase by zinc fertilization.