Abstract: Change of water physiology of potted plants Cymbidium sinense (Andr.) Willd. grown in different soil moisture condition were studied. Different age of leaf had different response to drought, 1-year-old leaf was sensitive than 2-year-old leaf. Among several physiological parameters, such as leaf water content, leaf water potential, chlorophyll content, transpiratory rate and stomatal resistance etc., last two parameters were the most sensitive to drought.

Key words: Cymbidium sinense

摘要： 研究了盆栽墨兰(Cymbidium sinense(Andr.)Willd．]在不同土壤含水量情况下的水分生理变化。不同叶龄的叶片对于干旱反应不同，一年生叶比二年生叶敏感。在叶片含水量、叶片水势、叶绿素含量、蒸腾速率和气孔阻力等生理参数中，后两者对干旱反应最灵敏。所以，一年生幼叶的蒸腾速率和气孔阻力可作为指标去判断墨兰植株水分供应情况。墨兰在土壤持水力44.2%时，相对透性较小，生长正常，一年生幼叶的蒸腾速率和气孔阻力分别是3.36μg.cm-2·s-1和7.08s·cm-1；当土壤干旱，持水力降至22.5%时，相对透性增大39%，说明细胞已经受旱害，该时的蒸腾速率降至0.95μg、cm-2.s-1,气孔阻力升为22.25s·cm-1。可以认为，墨兰的土壤临界水分是在土壤持水力44％－22％之间。

关键词: 墨兰, 土壤干旱, 蒸腾速率, 气孔阻力