【摘要】 水分胁迫初期,2个品种小麦幼苗脱落酸(ABA)只有少量增加,此后ABA迅速累积,胁迫后期,F_ (122)约增加20.7倍,丰8仅增加4.7倍。复水后均很快下降到对照水平。胁迫初期,小麦幼苗出现萎蔫症状之前,玉米素核苷(ZR)便迅速下降,然后再升高,随着胁迫的加剧再次下降,复水后又迅速回升。出现一“反冲”现象。F_ (122)幼苗中ZR在干旱处理的第2天便迅速下降了69.8％,而丰在干旱的第3天只下降了14.6％。这反映了2个品种小麦内源激素水平的变化对水分胁迫反应的差异。更多还原

【Abstract】 During the first few days of water stress, there is only little increase of ABA level in leaves of two varieties, then accumulates rapidly. In later days of stress, the increase in F₁₂₂ is greater and earlier than that of Feng₈(about 20.7-fold in F₁₂₂, and in Feng₈ only 4.7-fold). After rewatering, ABA content declines sharply to the control level, Before temporary wilting symptom occurs, zeatin riboside（ZR）level decreases drastically, then returnes to the control level. Following the severe stress, ZR declines again. Finally, decrease in ZR level is reversed by terminating water stress. It showed "counteract phenomenon". ZR level in F₁₂₂ decreased 69.8％ on the second day of withholding water, and in Feng₈ decreases only 14.6％ on the third day. These results showed that rapid decrease of CK level and then following increase of ABA level are adaptive physiological mechanism in wheat.更多还原