12种绿化乔木苗期抗旱性评价

为给中国南方地区鉴选抗旱植物提供参考依据,本研究测定了南方地区12种常见绿化乔木苗期干旱胁迫下的光合参数及相关生理指标,利用聚类分析综合抗旱评价法比较分析了其抗旱性。结果表明,随着干旱胁迫时间的延长,12种乔木苗的净光合速率、蒸腾速率、气孔导度、叶绿素含量及叶片相对含水量均逐渐降低,而电解质渗透率和丙二醛含量均逐渐增加。在干旱胁迫下,蒲葵、侧柏和火力楠各指标变化幅度较小,抗旱性最强;香樟、黄花风铃木和桂木抗旱性次之;大叶紫薇、台湾栾树、多花红千层、红锥、美丽异木棉和黄槐各指标变化幅度较大,抗旱性相对较差。在园林植物耐旱、节水配置中可以优选蒲葵、侧柏、火力楠、香樟、黄花风铃木和桂木作为建群树种。

Assessment on Drought Resistance of Twelve Green Arbors at Seedling Stage

Aiming to provide reference guide of choosing drought-resistant plants in southern China, the drought resistance of twelve green arbors at seedling stage was evaluated in this study. The photosynthetic parameters and physiological indicators of twelve green arbors at seedling stage were determined under drought stress, then the drought resistance of them was analyzed by means of cluster analysis method. The results showed that, as the time of drought stress went on, net photosynthetic rate, transpiration rate, stomatal conductance, chlorophyll content and relative water content gradually reduced, and electrolyte leakage, malonaldehyde content increased in twelve kinds of arbors. Moreover, the change of photosynthetic parameters and physiological indicators in Livistona chinensis, Platycladus orientalis and Michelia macclurei was relatively stable under drought stress, so they showed the best drought resistance; and Cinnamomum bodinieri, Tabebuia chrysantha and Artocarpus lingnanensis ranked in the middle group; while the change of each index in Lagerstroemia speciosa, Koelreuteria elegans, Callistemon rigidus, Castanopsis hystrix, Ceiba speciosa and Cassia surattensis were drastic under drought stress, so they were the least drought tolerant species. Consequently, L. chinensis, P. orientalis, M. macclurei, C. bodinieri, T. chrysantha and A. lingnanensis can be chosen preferentially as the major dominant species in garden plants arrangement, which will be helpful to achieve the effect of drought-resistant and water-saving.