续随子在山西太谷地区的光合特性研究

Study on Diurnal Variation of Photosynthesis of Euphorbia lathyris L. in Shanxi Province

续随子的种子富含油酸,是一种理想的生物柴油替代原料,有很大的发展前景。在自然环境下,采用CB-1102便携式光合仪,测定了续随子的净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)、胞间CO_2浓度(Ci)等光合生理生态因子,以及光合有效辐射(PAR)、田间CO_2浓度(Ca)、相对湿度(RH)等环境因子的日变化,以探究光合特性与栽培地区生理生态因素的关系。结果表明,续随子净光合速率变化呈现出双峰曲线,峰值分别出现在10:00和16:00左右,且第1个比第2个要高;11:00—14:00净光合速率快速下降,具有明显的午休现象;相关性分析结果表明,续随子叶片的净光合速率与蒸腾速率和气孔导度呈显著正相关,与胞间CO_2浓度呈显著负相关,但与环境温度、相对湿度和田间CO_2浓度相关性并不显著。

Euphorbia lathyris L. is a good biodiesel plant, which is rich in oleic acid, and has a great application prospects. Thediurnal dynamics of photosynthetic rate（Pn） , transpiration rate（Tr） , stomatal conductance（Gs）and internal CO2（Ci）of Euphorbialathyris L. as well as the ecological factors photosynthetically active radiation（PAR） , CO2 concentration in field（Ca） , relative humidity（RH）and air temperature（Ta）were measured by using the CB-1102 photosynthesis apparatus in natural environment in Taigu, Shanxiprovince to analyze the relationship between photosynthetic characterics and physio-ecological factors. The results showed that the netphotosynthetic rate of leaf showed double-peak pattern in sunny day. The peak values occured at 10：00 and 16：00, respectively, and thefirst peak was higher than the second. Net photosynthetic rate decreased rapidly from 11：00 to 14：00, an obvious midday depressionoccurred. The net photosynthetic rate was positively correlated with transpiration rate and stomatal conductance. There was a significantnegative correlation between net photosynthetic rate and intercellular carbon dioxide concentration. But the correlation between netphotosynthetic rate and ambient temperature, relative humidity and field CO2 concentration was not significant.