渗透胁迫下小麦的膜损伤与ABA增高的关系

The Relations between the Injury of Plasma Membrane and the Increase of ABA Content in Wheat Leaves

以渗透势为－０．６７ＭＰａ的ＰＥＧ根际处理小麦幼苗，在２４ｈ胁迫期间，叶片相对含水量（ＲＷＣ）和叶绿素含量下降，质膜透性于１８ｈ迅速升高，丙二醛（ＭＤＡ）含量在１２ｈ后急剧增加，超氧化物歧化酶（ＳＯＤ）活性下降，过氧化物酶（ＰＯＤ）活性升高；而ＡＢＡ含量在胁迫处理下的３ｈ和１５ｈ出现两个高峰．表明渗透胁迫下ＡＢＡ的积累在膜损伤之前．

When wheat seedlings were treated in the root with osmotic potiential of─0. 67MPa polyethylene glycol(PEG) for 24 h, the relative water content(RWC) and chlorphyll (Chl) content of the leaves declined. The permeability of plasma membrane was rapidly increased after 18 h, and the malondialdehyde (MDA) content speedily increased after 12 h while the activity of superoxide dismutase (SOD) decreased, but that of peroxidase (POD)increased and two peaks in the content of abscisic acid (ABA) appeared two peaks at 3 h and 15 h respectively. It shows that the increaes of ABA content occurred before the injury of plasma membrane.