屋顶绿化5种常绿植物的抗旱性研究

为了筛选更多耐粗放管理且抗旱性强的屋顶绿化常绿植物，选取在西安露地广泛应用且须根发达无主根的5种常绿灌木:金叶女贞、金边黄杨、南天竹、海桐、红叶石楠进行干旱胁迫，通过观察植株外部形态特征的变化，并对其叶片的生理指标:相对含水量、细胞质膜透性、叶绿素、丙二醛、脯氨酸的含量进行测定，利用隶属函数值法进行综合评价。结果表明，5种常绿灌木的抗旱性排序依次为金边黄杨＞海桐＞红叶石楠＞金叶女贞＞南天竹，应用于屋顶绿化时，金叶女贞、南天竹应加强灌溉措施。总体而言说明5种常绿灌木基本能适应西安市的气候条件和屋顶环境。

Drought Resistance of Five Kinds of Roof Greening Evergreen Plants

In order to select more roof greening plants with strong drought resistance and adaptability to low level management,five evergreen shrubs without main roots that are widely used in open field greening in Xian were selected as research objects,including Ligustrum×vicaryi,Buxus megistophylla,Nandina domestica,Pittosporum tobira,and Photinia×fraseri.The drought resistance of five shrub species were evaluated by measuring their morphological changes,water content,cytoplasmic membrane permeability,chlorophyll content,malondialdehyde content and proline content under the simulated drought conditions.The comprehensive evaluation using membership functions showed that the order of drought resistance from strong to weak was B.megistophylla＞P.tobira＞P.×fraseri＞L.×vicaryi＞N.domestica.The results indicated that irrigation measures should be strengthened when the shrub species with weak drought resistance were used in roof greening,such as L.×vicaryi and N.domestica.In short,the five evergreen shrub species could basically adapt to the climatic conditions and roof environment of Xi’an.