4种彩叶矾根的光合特性及在贵州的适应性

Photosynthetic Characteristics and Adaptability of Four Heuchera micrantha Varieties with Different Colourful Leaf in Guizhou

为矾根属植物在贵州以及西南地区园林景观的应用提供参考依据,以引入的4种彩叶矾根品种(天鹅绒、教堂窗户、李子布丁和银色卷轴)为试材,采用LI-6400XT光合仪对矾根品种进行光响应和CO2响应曲线测定,分析叶片光合日变化规律及其影响因子,明确不同矾根品种对光照环境的适应能力。结果表明:银色卷轴在贵州夏季寡日照环境下对弱光的利用能力较好,天鹅绒和教堂窗户对强光的适应性较好,较高的CO2浓度有利于提高天鹅绒品种的光合速率;李子布丁在强光下受光抑制较大,栽培上应避免强光造成的叶片灼伤。24h内相同环境条件下,4个矾根品种的净光合速率表现为教堂窗户>银色卷轴>天鹅绒>李子布丁;4个品种的净光合速率与气孔导度、胞间CO2浓度、蒸腾速率及空气相对湿度均呈正相关性,其中教堂窗户净光合速率和气孔导度呈显著正相关。

The photoresponse and CO2 response curve of four introduced Heuchera micrantha varieties were determined by LI-6400XT photosynthesis apparatus and then the leaf diurnal variation pattern and influence factors were analyzed to identify the adaptive capacity of different H.micrantha varieties to light environment and to provide a reference for application of H.micrantha plants in landscape architecture in Guizhou and Southwest area.Result:Silver Scrolls variety has a good utilization capacity under the weak light environment in summer in Guizhou but Velvet Night and Cathedral Windows varieties have the good adaptability to high light.The higher CO2 concentration is beneficial to improving photosynthetic rate of Velvet Night variety.Plum Pudding variety performances a greater light inhibition under the strong light environment.The net photosynthetic rate of four H.micrantha varieties is Cathedral Windows>Silver Scrolls>Velvet Night>Plum Pudding under the same environment condition within 24 h.The net photosynthetic rate of four H.micrantha varieties is positively related to stomatal conductance,intercellular CO2 concentration,transpiration rate and relative air humidity.There is a significant positive correlation between net photosynthetic rate and stomatal conductance in Cathedral Windows variety.