金镶玉竹、黄秆乌哺鸡竹和黄纹竹在北京地区冬季的耐寒生理和叶片结构比较

对移栽到北京6 a的金镶玉竹、黄秆乌哺鸡竹和黄纹竹冬季越冬期的叶片结构、光合荧光特性、相对电导率等进行研究.结果表明:(1)3个竹种叶片上表皮无显著变化,下表皮黄秆乌哺鸡竹和黄纹竹的机械损伤程度大于金镶玉竹,黄秆乌哺鸡竹和黄纹竹气孔器宽度下降幅度显著小于金镶玉竹,黄纹竹叶片致密度、气孔密度下降幅度最大;(2)黄秆乌哺鸡竹净光合速率(P_n)、蒸腾速率(T_r)和气孔导度(G_s)变化幅度大于金镶玉竹,而黄纹竹的却小于金镶玉竹,F_v/F_m值降幅表现为金镶玉竹黄秆乌哺鸡竹黄纹竹;(3)金镶玉竹和黄秆乌哺鸡竹叶片的相对电导率变化幅度差异不显著,黄纹竹的叶片和鞭根相对电导率的变化幅度差异显著.

Changes in physiological indices and leaf structure of Phyllostachys aureosulacata f. spectabilis,Ph. vivax f. aureocaulis,Ph. vivax f. huangwenzhu during winter in Beijing

For wide application of bamboo species, growth mechanism of 3 kinds of bamboo planted in Beijing, including Phyl-lostachys aureosulacata f. spectabilis, Ph. vivax f. aureocaulis, Ph. vivax f. huangwenzhu , was compared in terms of leaf ultrastruc-ture, photosynthetic characteristics and fluorescence, electric conductivity after winter. The results showed that there were no signifi-cant variations in upperepidermis among 3 species, but physical damages were more serious in underepidermis of Ph. vivax f. aureo-caulis, Ph. vivax f. huangwenzhu than Phyllostachys aureosulacata f. spectabilis. Fluctuation in stomatal width was smaller in Ph. vivax f. aureocaulis and Ph. vivax f. huangwenzhu than Phyllostachys aureosulacata f. spectabilis. Compared with Phyllostachys aureo-sulacata f. spectabilis, net photosynthetic rate ( Pn ) and transpiration rate ( Tr ) stomatal conductance ( Gs ) varied more significantly in Ph. vivax f. aureocaulis, but less in Ph. vivax f. huangwenzhu . The decline rate of Fv/Fm in an ascending order was Phyllostachys aureosulacata f. spectabilis