Four levels of drought stress were applied to 1 -year-old potted seedlings of Sorbus folgneri to investigate the effects drought on seedling growth and physiological characteristics. The results showed that drought had significantly reduced seedling height, diameter, leaf area, increased main root length and lateral root number. Drought decreased biomass accumulation, altered biomass allocation patterns, led more photoaynthetic products transfer to belowground parts, caused higher root to shoot ratio for the decreasing of stem and leaf mass ratio, and increasing of root mass ratio. With drought stress intensity increasing and duration exten-sion, leaf relative water content maintain stably in control and light stress, but reduced continually in moderate and heavy str0ese, and both soluble sugar content and malonic dialdehyde content increased remarkably.%采用盆栽控水设置4种干旱胁迫梯度,研究干旱胁迫对1年生石灰花楸幼苗生长和生理的影响.结果表明,随干旱胁迫的加剧,幼苗变矮,地径变细,叶面积减小,主根变长,侧根数增加；干旱降低了幼苗生物量积累,生物量分配方式向有利于根系水分吸收的方向转变,茎叶生物量比降低,根生物量比增加,根冠比变大；随着干旱胁迫持续时间延长:石灰花楸幼苗的叶片相对含水量在对照和轻度胁迫下保持基本稳定,在中度和重度胁迫下则持续降低；干旱胁迫下可溶性糖和丙二醛含量增加.
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