黄瓜净光合速率时间变化及影响因子的相关分析

以嫁接黄瓜(Cucumis sativus L.)为材料,在不同天气下采用LI-6400型便携式光合仪测定其结瓜期净光合速率,并分析其与影响因子的相关性。结果表明,无论晴天还是阴天,大棚嫁接黄瓜的净光合速率、光合有效辐射、气孔导度和蒸腾速率均呈单峰型变化,胞间CO2浓度无论晴天还是阴天均呈"U"型变化,叶温无论晴天还是阴天均呈倒"U"型变化。晴天嫁接的黄瓜,其净光合速率的最优化多元回归方程为y=26.077 5+0.000 6x1+15.809 0x3-0.080 4x4,阴天为y=72.594 6+0.043 6x1+2.812 9x3+0.187 6x4;偏相关和通径分析表明,晴天对净光合速率的影响顺序为气孔导度光合有效辐射蒸腾速率胞间CO2浓度。阴天为光合有效辐射胞间CO2浓度叶温。

Correlation Analysis on Net Photosynthetic Rate and Impact Factors of Grafted Cucumber

The correlation between the diurnal change of net photosynthetic rate and impact factors of the grafted cucumber (Cucumis sativus L.)in fruiting stage was analyzed by LJ-6400 photosynthesis measure system. The results indicated: Net photosynthetic rate, photosynthesis effective radiation, stomatal conductance and transpiration rate of grafted cucumber were all single-peak curve whenever in sunny day or cloudy day. The concentration of CO_2 in intercellular space changed as "U" and the leaf temperature changed as inverted "U". The optimization equation of P_n in sunny day attained by the method of stepwise multi-regression was y=26.077 5+0.000 6x_1,+15.809 0x_3-0.080 4x_4, in cloudy day was y=72.594 6+0.043 6x_1+2.812 9x_3+ 0.187 6x_4. The analysis of partial correlation and path showed that the diurnal variation of P_n had significant correlation with PAR and Cond, the order of effecting ability was Cond > PAR >T_r > C_i in sunny day and PAR> C_i > T_i in cloudy day.