不同柑橘品种光合生理生态特性的日变化

Daily Variation of Photosynthetic Physio-ecological Characteristics of Different Citrus Cultivars

在自然条件下,利用LI-6400便携式光合测定仪对温州蜜柑、本地早、金柑3个柑橘品种的光合速率及相关生理生态因子日变化进行了研究。结果表明:各品种的光合速率差异明显,温州蜜柑的最高,本地早次之,金柑的最小。温州蜜柑与本地早的光合速率日变化为双峰曲线,有光合"午休"现象,而金柑为单峰曲线。各品种光合速率与温度、光合有效辐射、气孔导度和蒸腾速率呈正相关,其中与光合有效辐射、气孔导度和蒸腾速率的相关程度达到极显著水平,而与空气相对湿度、外界CO2浓度和胞间CO2浓度呈负相关。各品种水分利用率日变化均表现为降低,且品种间无显著差异。

The results from determining photosynthetic rate and correlation physio-ecological factors of three citrus cultivars(Unshiu,Bendizao and Kumquat) by LI-6400 Portable Photosyntometer under the natural condition showed that there was obviously difference in photosynthetic rate between three citrus cultivars and the order of photosynthetic rate was Unshiu> Bendizao > Kumqua,the daily variation of;photosynthetic rate of Unshiu and Bendizao showed double peaks with the phenomenon of 'midday rest' and the daily variation of photosynthetic rate of Kumquat showed single peak.There were significant positive correlations between photosynthetic rate and photosynthetic active radiation(PAR),stomatal conductance(Cond),transpiration rate(Tr) in three citrus cultivars.There was a positive correlation between photosynthetic rate and temperature in three citrus cultivars and there were negative correlations between photosynthetic rate and air relative humidity(RH),air CO2 concentration(Ca),intercellular CO2 concentration(Ci) in three citrus cultivars.The daily variation of water use efficiency(WUE) of three citrus cultivars showed a decline trend and there was no significant difference between different cultivars.