Abstract: In order to clarify the effect of nitrogen application on diurnal variation of photosynthesis and yield of Lycium species, Lycium ruthenicum and Lycium barbarum were selected and 5 nitrogen application treatments including 0(CK), 50(F1), 100(F2), 150(F3) and 200 (F4)g·plant^-1 were set up. The net photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (Gs), intercellular CO2 concentration (Ci), instantaneous water use effiency (WUE), stomatal limitation (Ls) and yield of L. ruthenicum and L. barbarum transplanted to arid areas in Wuwei City, Gansu Province were studied. And the best nitrogen application amount was fitted from the perspective of photosynthesis increasing yield. The results showed that nitrogen application could increase Pn, Tr, Gs, WUE and yield of L. ruthenicum and L. barbarum in different time periods of 1 d, reduce Ci and Ls of the two Lycium species, thus increase their photosynthesis. The effect of nitrogen application on photosynthetic parameters of L. ruthenicum was more significant than that of L. barbarum. The daily average net photosynthetic rate (PnA) and yield of L. ruthenicum in F3 treatment were the highest, with 9.842 μmol·m^-2·s^-1 and 173.621 g, respectively. PnA of L. barbarum in F3 treatment was the highest, which was 11.616 μmol·m^-2·s^-1; its yield in F3 treatment was the highest, which was 205.264 g·plant^-1. Therefore, nitrogen application with 150 g·plant^-1 was beneficial to increase photosynthesis of L. ruthenicum and L. barbarum, thus could obtain the maximum yield.

Key words: Lycium ruthenicum Murr., Lycium barbarum L., N application amount, photosynthesis diurnal variation, yield

摘要： 为阐明施氮对枸杞的光合日变化特性及产量的影响，选择黑果枸杞（Lycium ruthenicum）和宁夏枸杞（Lycium barbarum）两个物种，设置0（CK）、50（F1）、100（F2）、150（F3）和200 （F4）g·株^-1共5个施氮处理，研究移栽至干旱区甘肃省武威市的黑果枸杞和宁夏枸杞的净光合速率（net photosynthetic rate，Pn）、蒸腾速率（transpiration rate，Tr）、气孔导度（stomatal conductance，Gs）、胞间CO2浓度（intercellular CO2 concentration，Ci）、瞬时水分利用率（water use efficiency，WUE）和气孔限制值（stomatal limitation，Ls）的日变化及产量，并通过光合作用提高产量的角度对最佳施氮量进行拟合。结果表明,施氮能提高黑果枸杞和宁夏枸杞1 d内各时间段的Pn、Tr、Gs、WUE及产量，降低两种枸杞1 d内各时间段的Ci和Ls，有利于光合作用的进行；施氮对黑果枸杞各光合参数的影响较宁夏枸杞更显著。F3处理下黑果枸杞的日平均净光合速率(PnA)和产量最佳，分别为9842 μmol·m^-2·s^-1和173.621 g；施氮187.730 g·株^-1的宁夏枸杞的PnA最佳，为11.616 μmol·m^-2·s^-1；F3处理的宁夏枸杞的产量最佳，为205.264 g·株^-1。因此，施氮150 g·株^-1有利于提高黑果枸杞和宁夏枸杞的光合作用，进而获得最大产量。

关键词: 黑果枸杞, 宁夏枸杞, 施氮, 光合日变化, 产量