干旱胁迫对黄栌幼苗几个生理指标的影响

研究了干旱胁迫对黄栌幼苗的相对含水量、膜透性、叶绿素含量、根系活力以及蒸腾和光合速率等几个生理指标的影响．结果表明：干旱胁迫对黄栌幼苗的几个生理指标影响显著；随着干旱胁迫程度的加剧和时间的延长，黄栌的叶绿素含量稳定上升；膜透性在整个干旱胁迫期间变化平稳，有下降趋势；蒸腾速率日变化均为先升后降的趋势；在干旱胁迫条件下，净光合速率、根系活力和相对含水量均呈下降趋势，但能持续维持在较高水平．黄栌具有抗旱性，叶绿素含量和膜透性能作为黄栌抗旱性评价的生理指标．

Effects of Drought Stress on Several Physiological Indexes of Cotinus coggygria Seedlings

Effects of drought stress on several physiological indexes of Cotinus coggygria seedlings were studied. The results show that the physiological indexes were significantly influenced under drought stress. As the stress of drought was intensified, the contents of chlorophyll of Cotinus coggygria kept on increasing and the plasma membrane permeability was stable in the course of drought and a declining trend appeared. The diurnal change of Tr all took on an increasing and then declining trend, and the net photosynthesis rate. roots activity and the relative water content all declined under drought stress but they still kept at a high level. The results indicate that Cotinus coggygria has a character of drought tolerance. The contents of chlorophyll and the plasma membrane permeability could be used as appraising water-resistance indexes for Cotinus coggygria.