4个油桐品种光合特性的日变化研究

The Study on Daily Changes of Photosynthetic Characteristics of 4 Cultivars of Tung Tree(Vernicia fordii)

为了研究油桐光合效率的高低及不同品种之间光合特性的差异,筛选高光效的油桐品种,利用Li-6400便携式光合测定系统,测定了4个油桐品种光合指标的日变化。结果表明:(1)‘葡萄桐’、‘小米桐’、‘对年桐’的净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)日变化均呈单峰曲线,‘大米桐’的Pn、Gs、Tr日变化呈双峰曲线;(2)4个品种的胞间CO2浓度(Ci)日变化呈不规则的"V"字型;(3)4个品种净光合速率日变化平均值大小排序为:‘葡萄桐’>‘小米桐’>‘对年桐’>‘大米桐’;(4)影响油桐净光合速率值的主要生态生理指标大小依次为:蒸腾速率>胞间CO2浓度>光合有效辐射>气孔导度。油桐具有较高的光合效率,不同品种之间的光合特性有所差异。

The aim was to study high and low of photosynthetic efficiency and differences of photosynthetic characteristics between different cultivars of tung tree, and screen high photosynthetic efficiency of cultivars of tung tree. The photosynthetic characteristics of 4 cuhivars of tung tree were measured with Li-6400 photosynthetic instrument. The results showed that： （1） net photosynthetic rate, stomatal conductance and transpiration rate of ＇Putaotong＇, ＇Xiaomitong＇ and ＇Duiniantong＇ changed as single peak curve, while ＇Damitong＇ changed as bimodal peak curve; （2） Intercellular CO2 between 4 cultivars of tung tree concentration appeared to vary in a V-shaped curve; （3） The order in daily change of average net photosynthetic rate of them taken as ＇Putaotong＇〉＇Xiaomitong＇〉＇Duiniantong＇〉＇Damitong＇; （4） The impact order that main ecological physiological of net photosynthetic value of tung tree was transpiration rate〉 intercellular CO2 concentration〉PAR〉stomatal conductance. Tung tree had high photosynthetic efficiency and photosynthetic characteristic differences between different varieties.