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１９９４～１９９６年对梨树在自然水分亏缺和水分充足条件下的主要水分生理参数、气孔相对开张度（ＲＳＯＤ）、蒸腾速率（Ｔｒ）和光合速率（Ｐｎ）进行了比较研究。结果表明，梨树属于低水势耐旱类型，在自然水分亏缺下，其叶水势（ψｗ）显著降低，膨压（ψｐ）明显增高，而ＲＳＯＤ、Ｔｒ和Ｐｎ则无显著变化。梨树具有明显的渗透调节和一定的弹性调节作用，在中度水分亏缺下，其渗透调节能力△π１００或△π０分别为０．４４ＭＰａ和０．７７ＭＰａ，弹性调节能力△｜β｜和△εｍａｘ分别为２．７８和３．１９。另外，在自然水分亏缺下，梨树叶片还具有较强的保水能力，反映在基本无变化的膨压消失点的相对含水量（Ｒ０）、叶表面水分散失率（ＷＬ０）和明显高于ＣＫ的一定ψｗ下的相对含水量（Ｒ）值以及无灌溉园较高的εｍａｘ或｜β｜等方面。
The main water physiological parameters, stomatal openness (RSOD), transpiration rate (Tr) and photosynthetic rate (Pn) of pear under natural water deficit and water deficit from 1994 to 1996 were compared. The results showed that pear tree was a low waterlogging and drought tolerant type. Under natural water deficit, its leaf water potential (ψw) decreased significantly, while turgor pressure (ψp) increased significantly. However, RSOD, Tr and Pn showed no significant changes. Pear tree has obvious osmotic adjustment and some elastic regulation. Under moderate water deficit, its osmotic adjustment △ π100 or △ π0 is 0.44MPa and 0.77MPa respectively, elastic adjustment △ | β | and △ εmax are 2.78 and 3.19, respectively. In addition, under the natural water deficit, pear leaves also have a strong ability to retain water, reflecting the relatively unchanged turgor vanishing point relative water content (R0), leaf surface water loss (WL0) and significantly higher than The relative water content (R) under a certain ψw of CK and the εmax or | β |