Abstract: In this research, some cultivars of [WTBX]Lycium barbarum[WTBZ] were taken as the materials. In the field experiment, the chlorophyll fluorescence parameters and the chlorophyll contents in the cultivars of [WTBX]L. barbarum[WTBZ] were studied using the chlorophyll fluorescence measuring technique. The results revealed that the maximal photochemical efficiency of PSⅡ [WTBX](Fv/Fm)[WTBZ] and potential activity of PSⅡ [WTBX](Fv/Fo)[WTBZ] of Ningqi No.2 were remarkably higher than those of other three cultivars. The actual photosynthesis yield [WTBX](Y[WTBZ](Ⅱ)), activity photosynthesis yield [WTBX]（Fv′/Fm′）,[WTBZ] photochemical quenching [WTBX](qP)[WTBZ] and electron transport rate [WTBX](ETR)[WTBZ] were significantly different from different cultivars under a photo synthetically active radiation of 0-2 847 μmol·m-2·s-1, and they were the highest in Ningqi No.2, followed by Mengqi No.1 and Damaye, and the lowest in Ningqi No.1. The initial slope α of fitting parameter [WTBX]ETR[WTBZ] was similar to the change trend of [WTBX]ETR.[WTBZ] The content of Chlorophyll a, Chlorophyll b and Chlorophyll a+b in Ningqi No.2 were the highest. There was an extremely significant or a significant positive correlation between chlorophyll a+b and [WTBX]Y[WTBZ](Ⅱ), [WTBX]Fv′/Fm′, qP[WTBZ] and [WTBX]ETR,[WTBZ] but a negative correlation with [WTBX]NPQ.[WTBZ] So it could be concluded that Ningqi No.2 had a higher physiological activity of PS II and physiological basis of potential biomass, the photosynthesis capability of all the four cultivars was strong. The photochemical efficiency of Ningqi No.1 was weaker, and it was easy to suffer from photo inhibition at high light intensity.

Key words: font-size: 10.5pt, mso-bidi-font-family: 宋体, mso-font-kerning: 1.0pt, mso-ansi-language: EN-US, mso-fareast-language: ZH-CN, Lycium barbarum[WTBZ]')">mso-bidi-language: AR-SA" lang="EN-US">Lycium barbarum[WTBZ], chlorophyll content, chlorophyll fluorescence parameter, Gansu province