黑果枸杞光合作用日变化规律研究

以盆栽的黑果枸杞组培苗为材料,自然条件下用便携式光合-荧光测量系统GFS-3000对黑果枸杞光合作用进行测定,对影响其光合作用的生理因子和环境因子进行相关性分析。结果表明:黑果枸杞净光合速率的日变化在夏季表现为双峰曲线,有光合"午休"现象,日平均光合速率为10.27μmol/m~2·s;光补偿点(LCP)为41.31μmol/m~2·s,光饱和点(LSP)为1698.88μmol/m~2·s,表现出阳性植物特征,适合在光照充足的地区栽培;表观量子效率(AQY)为0.051,这说明黑果枸杞对光的利用率较高,有较强的光合能力。相关分析结果表明黑果枸杞的净光合速率(Pn)与光合有效辐射(PAR)、叶室温度(Tcu)、叶片温度(Tl)、大气温度(Ta)、气孔导度(Gs)及蒸腾速率(Tr)具有极显著正相关关系(p0.01),与空气CO_2浓度(Ca)显著正相关(p0.05),与胞间CO_2浓度(Ci)具有极显著负相关关系。

Studies on diurnal change of photosynthesis of Lycium ruthenicum [Solanales：Solanaceae]

Using pot cultured plantlets of the black fruit wolfberry, Lycium Ruthenicum, as material, the photosynthesis of the plants was measured under natural conditions with a portable photosynthesis - fluorescence measurement system -GFS-3000. The correlation between physiological and environmental factors affecting the photosynthesis was also ana-lysed. The results showed that the diurnal variation of net photosynthetic rate registered a double-peak curve in summer and had “midday depression” phenomenon in L. ruthenicum. The mean diurnal photosynthetic rate was 10.2 μmol/ m2 · s; light compensation point (LCP) was 41.31 μmol/ m2 ·s, light saturation point (LSP) was 1698.88 μmol/ m2 ·s. Ly-cium ruthenicum manifests the characteristics of heliophile and is suitable to be planted in well-lit areas. Apparent quan-tum yield (AQY) of 0.051 indicates that L. ruthenicum’s light utilization rate is higher and has the strong photosynthetic capacity. Correlation analysis showed that the net photosynthetic rate (Pn) of L. ruthenicum has (1) a significant positive correlation (p < 0.01) with photosynthetically active radiation (PAR), chamber temperature (Tcu), leaf temperature (Tl), air temperature (Ta), stomatal conductance (Gs), and transpiration rate (Tr); (2) significant positive correla-tion (p < 0.05) with air CO2 concentration (Ca); (3) a significant negative correlation (p < 0.01) with intercellular CO2 concentration (Ci).