桂花幼苗对不同程度水分胁迫的生理响应

以二年龄盆栽桂花为试材,研究其对不同程度水分胁迫的生理响应。结果表明:当胁迫程度加深时,桂花幼苗叶片的组织水、自由水含量及自由水和束缚水含量的比值明显降低,轻度胁迫与对照间束缚水含量无显著差异,但中度胁迫和重度胁迫与对照相比差异显著;细胞膜相对透性、MDA、可溶性糖和脯氨酸的含量随着处理时间的延长而升高,胁迫程度的加重,升高加快;在胁迫过程中,重度胁迫和中度胁迫的POD和CAT活性呈先上升后下降的趋势,但它们达到高峰的时间不同,重度胁迫在第6天达到高峰,中度胁迫在第9天达到高峰;轻度胁迫时2种酶的活性均呈上升的趋势。

Physiological Responses of Osmanthus fragrans Lour.Young Trees to Different Water Stress

Two-year-old Osmanthus fragrans Lour.was potted to study the physiological responses to different water stress.The results were as followings:The tissue water content,free water content and the ratios of the free water content to bound water content decreased obviously when the condition of the water stress become severe;the bound water content of severe and moderate water stress significantly differed from control while the mild water stress was not.The relative membrane permeability,MAD content,soluble sugar and praline content increased during the process of water stress.The activity of POD and CAT under severe and moderate water stress increased firstly and then decreased during the period of water stress.The activity of POD and CAT under the severe water stress reached the peak on the 6th day while that of the moderate water stress on the 9th day.The activity of POD and CAT under mild water stress increased along the time.