| Abstract:In order to find out the optimal nitrogen application rate for the cultivation of Lycium ruthenicum Murr.Under single-factor randomized block design, five nitrogen application gradients(0，50 g·plant-1, 100 g·plant-1, 150 g·plant-1, 200 g·plant-1)through three stages(initial fruit stage, summer fruit stage, and autumn fruit stage) was set to study the effects of different nitrogen rates on photosynthetic characteristics and yield of Lycium ruthenicum. The results showed that proper nitrogen application could increase chlorophyll(Chl) content, net photosynthetic rate(Pn), maximum net photosynthetic rate(Pnmax), transpiration rate(Tr), stomatal conductance(Gs), and water use efficiency(WUE), apparent quantum efficiency(AQY), 100-grain mass, yield per plant, and the ability to use weak light and reduce intercellular CO2 concentration(Ci). Correlation analysis showed that the correlation between Chl content and Ci was the most significant. When the annual nitrogen application rate was 150 g·plant-1, the Pnwas the highest, and it was 67.6%, 54.1% and 44.0% higher than that of no nitrogen applicationat the three stages; when the annual nitrogen application rate was 150 g·plant-1 or 200 g·plant-1, the yield per plant was the highest,the maximum yield of single plant at the three stages was 27.6%, 32.9% and 52.3% higher than that of no nitrogen application. It showed that the photosynthesis of Lycium ruthenicum was the maximum when the annual nitrogen application rate was 150 g·plant-1, and the yield was maximum when the nitrogen application rate was 150 or 200 g·plant-1. |
