5个香椿种源的光合响应研究

Study on Light Response Curve of Photosynthesis among 5 Provenances of Toona sinensis

对5个香椿(Toona sinensis)种源1a生苗木进行光合响应测定和分析,研究香椿种源间光合特性的差异。结果表明:净光合速率(P_n)、气孔导度(G_s)、胞间CO_2浓度(C_i)、蒸腾速率(T_r)、水分利用效率(WUE)5个指标对光量子通量密度(PFD)的响应在种源间存在显著差异(P<0.05)。最大净光合速率(A_(max))值从大到小分别为重庆彭水种源、广西那坡种源、湖南凤凰种源、福建漳州种源、贵州独山种源。表观量子效率(AQY)变幅为0.041~0.052μmol·mol^(-1),偏大,香椿的叶片在较弱光强下的光能转化率较高。光合补偿点(LCP)范围为19.483~33.594μmol·m^(-2)·s^(-1),光合饱和点(LSP)范围为318.25~513.586μmol·m^(-2)·s^(-1)。重庆彭水种源适应性最强,广西那坡种源适应强光的能力较强,其余3个种源对强、弱光适应性都较弱。

This research studied the difference provenances and provided the basis for the breeding of T. provenances of T. sinensis＇ test result showed that photosynthetic rate （ P, ） , stomatal conductance （ G ） , of photosynthetic characteristics between Toona sinensis sinensis. The photosynthetic response of 1 a seedlings of 5 there were significant differences in responses of net intercellular CO2 concentration （ Ci ）, transpiration rate （Tr） and water use efficiency （WUE） to photon flux density （PFD） among the responses of maximum net photosynthetic rate （Am=） value was Pengshui of Chongqing, Napo of Guangxi, Fenghuang of Hunan, Zhangzhou of Fujian, Dushan of Guizhou. The apparent quantum yield （AQY） was 0. 041--0. 052 μmol . mol^-1. The AQY was higher than normol value. This result indecated T. sinensis leaves light conversion rate was higher under the weak. The range of light compensation point （LCP） is 19. 483-33.594 μmol . m^-2 . s^-1, the light saturation point （LSP） range is 318.25--513. 586 μmol . m^-2 . s^-1 Pengshui provenance adaptability was the strongest. Napo provenances adapt to strong light. The adaptability of other 3 provenances of strong and weak light are weak.