干旱胁迫对4种景天科植物生理生化指标的影响

为筛选适合北方地区的屋顶绿化植物，以4种景天科植物为试材，采用盆栽控水法研究干旱胁迫对植物叶片相对含水量、相对电导率及丙二醛含量等抗旱性生理指标的影响，并结合植物生长状况及隶属函数法综合评价4种植物的抗旱能力强弱。结果表明，随着干旱胁迫时间的增加，形态上卧茎景天(Sedum sarmentosum)、长药景天(Hylotelephium spectabile)和堪察加景天(S. kamtschaticum)的评价等级为生长一般，德国景天(S. hybridum cv.Immergrunchell)生长受抑制。各种景天的叶片相对含水量都呈下降趋势，卧茎景天的相对电导率及丙二醛含量增幅较小，抗旱性较强。通过隶属函数综合评价，4种景天植物的抗旱能力大小为卧茎景天>长药景天>堪察加景天>德国景天。

Effect of drought stress on physiological indexes of 4 Crassulaceae species

In order to select green roof plants in north cold area,the effects of drought stress on 4 Crassulaceae species of physiological indexes were studied,including leaf relative water content,relative electrical conductivity,MDA (malondialdehyde) content,combined with subordinate function comprehensive evaluation of plant drought resistance ability.With the extension of drought stress,S.sarmentosum,H.spectabile and S.kamtschaticum was identified as normal growth and S.hybridum cv.Immergrunchell was identified as inhibited growth by means of morphological evaluation.Leaf relative water content of Sedum leaves decreased.The relative electrical conductivity and MDA content of S.sarmentosum increased slightly which indicated it has high drought resistance.The drought resistance of 4 Crassulaceae species were comprehensive evaluated with subordinate function and their drought resistance order as following:S.sarmentosum>H.spectabile>S.kamtschaticum>S.hybridum cv.Immergrunchell.