华南地区4种园林绿化树种的光合对水淹胁迫响应

Photosynthetic response of four garden greening seedling types to waterlogging stress in south China

以灰木莲(Manglietia glauca)、尖叶杜英(Elaeocarpus apiculatus)、蒲桃(Syzygium jambos)和乐昌含笑(Michelia chapensis)4种园林绿化树种的幼苗为研究对象,对其淹水胁迫处理下的光合响应生理机制进行探讨,以期为华南地区筛选耐水淹树种提供参考。结果表明,随着水淹胁迫时间的增加,4种幼苗的净光合速率Pn、气孔导度Gs和蒸腾速率Tr呈下降趋势,35 d时均达到最小值,灰木莲的胞间CO2浓度Ci逐渐上升,尖叶杜英的Ci先降后升,蒲桃和乐昌含笑的Ci均缓慢下降。综合考虑4个叶片气体交换参数,运用主成分分析法得出4种幼苗耐水淹能力为蒲桃>乐昌含笑>尖叶杜英>灰木莲。

Leaf gas exchange parameters of Manglietia glauca, Elaeocarpus apiculatus, Syzygiumjambos, Michelia chapensis seedlings Under waterlogging stress were investigated, so as to study the physiological response of the four seedling types to waterlogging resistance, and provide a reference for the selection of waterlogging resistant species in south China. The result showed that net photosynthetic rate （Pn）, stomatal conductance （Gs）, transpiration rate （Tr） of the four seedling types tended to decrease with increasing waterlogging time and all parameters reached their minimum at 35 days under waterlogging stress. Intercellular CO2 concentration （Ci） of M. glauca gradually increased, whereas that of E. apiculatus decreased followed by an increase, andthat of S. jambos and M. chapensis gradually decreased. The waterlogging resistance of the four seedling types was evaluated using principal component analysis, and their order of waterlogging resistance was S. jambos 〉 Mi. chapensis 〉 E. apiculatus 〉 M. glauca.