干旱胁迫对5种景天属植物生理指标的影响

Effect of drought stress on physiological indexes of 5 Sedum species

以5种景天属植物为材料,研究了景天属植物对干旱胁迫的生理响应机理,为选择低成本、适于大面积推广的轻型屋顶绿化植物提供理论依据。试验对5种材料进行干旱胁迫处理,每隔7d测定叶片组织含水量、相对电导率、丙二醛(MDA)、超氧化物歧化酶(SOD)和脯氨酸(Pro)含量的变化,共处理28d。结果表明,随着干旱胁迫时间的增加,叶片组织含水量明显下降,而相对电导率、丙二醛含量和脯氨酸含量却明显上升,超氧化物歧化酶活性则呈现先上升后下降的趋势。经综合评价,5种景天植物的抗旱能力大小为:垂盆草Sedumsarmentosum>佛甲草Sedumlineare>遍地黄金S.linearecv.‘Jin Ye’>凹叶景天S.emarginatum>胭脂红景天S.spuriumcv.‘Coccineum’。

Physiological response mechanism of Sedum was studied with five Sedums, which aimed to provide theoretical basis for selecting low cost and suitable plants of green roofs. In this study, five Sedums were exposed to drought stress （without irrigation） for 28 days. All measurements were determined in seven days intervals, including leaf water content, relative electric conductivity, malondialdehyde（MDA）, superoxide dismutase（SOD） and proline（Pro）. The results indicated that leaf water content decreased significantly with increase of the stress time, while relative electric conductivity, MDA and Pro increased, however, SOD activities were raised first and declined continually later. Through comprehensive analysis, it was concluded that the drought resistant abilities of these five sedums ordered as Sedum sarmentosum〉S, lineare〉S, lineare cv. ＇Jin Ye〉 S. emarginatum〉S. spurium cv. ＇Coccineum＇.