9个主要丛生竹种光响应曲线的研究

A Study on Light Response Curve of Photosynthesis of Nine Sympodial Bamboo Species

通过对我国9个主要丛生竹种光合光响应曲线研究,结果表明:当光强刚开始增强时,各竹种间差异较小,但随着光强增加,不同竹种出现很大的差异。各竹种的净光合速率随光合有效辐射升高达到最高点之后稳定下来,光抑制现象不明显。蒸腾速率和气孔导度对光响应的变化趋势与光合速率相似,胞间CO2浓度对光合有效辐射的响应趋势则与光合速率相反。9个参试竹种净光合速率在5.209～15.862μmol·m-2·s-1之间,最大的为绿竹,最小的为慈竹和粉单竹。光饱和点在685.820～1 896.791μmol·m-2·s-1之间,硬头黄竹最高,大木竹最低。光补偿点则是粉单竹最低为4.509μmol·m-2·s-1,慈竹最高。综合各指标和光响应变化规律,确定绿竹、黄竹和硬头黄竹为优良的高光效竹种,可在水分和光照条件好的地方适当推广。

Light responses of photosynthesis of 9 sympodial bamboo species were measured in this study. The results showed that at the beginning of light increase, differences in the photosynthetic rate （Pn） between bamboo species were not distinct, however, with the increase in light intensity, great differences in Pn between bamboo species appeared. Pn of each bamboo species reached the highest point with the increase of photosynthetically active radiation and then stabilized, the phenomenon of light suppression was not obvious. The light response of Tr and Cond were similar with Pn, and that of Ci was opposite to Pn. The potential photosynthetic rates ranged from 5. 209 μmol·m^-2·s^-1. to 15. 862 μmol·m^-2·s^-1 Of these, potential photosynthetic rate of Dendrocalamus oldhami was the highest, and that of Arundinaria oleosa and Pleioblastus amarus were the lowest. The light saturation points ranged from 685. 820 μmol·m^-2·s^-1 s to 1 896. 791 μmol·m^-2·s^-1 ,the highest was in rigida,the lowest was in Bambusa wenchouensis. The highest light compensation point was found in Bambusa emeiensis, and the lowest was in Bambusa chungii. In terms of the comprehensive analysis of various light response indexes of the 9 sympodial bamboo species, Dendrocalamus oldhami, Dendrocalamus membranaceus and rigida could be selected as the eminent high efficient bamboo species to be expanded in favorable water and light conditions.