植物水势系数及其应用实例

本文提出了植物水势系数的概念与计测公式，即植物水势系数是植物水势占大气水势和土壤水势对植物水势产生直接影响力那部分水势之和的比值。并对在塔克拉玛干沙漠生长的沙生柽柳进行了应用实例的验证。结果表明，在自然状态下，植物水势系数可作为衡量植物对环境胁迫反应强弱的一个指标。

PLANT WATER POTENTIAL COEFFICIENT AND ITS APPLICATION IN FIELD EXPERIMENT

An effort was made to put forward an index-plant water potential coefficient (PWPC) in the paper, and its calculation formula was given. Taking the inter-relationship of components in SPAC into account, the PWPC is defined as the ratio of plant water potential to the sum of air water potential and soil water potential that impose direct influence on plant water potential. The application of the PWPC in field experiment was illustrated. The experimental plant, Tamarix taklamakanensis M. T. Liu, was cultivated with furrow irrigation and non-irrigation in the hinterland of Taklimakan Desert. Under the conditions of non-irrigation, the relationship between PWPC of the plant and plant water potential appeared to be negative, and their correlation coefficient was - 0.98. The plant water potential was lower in hot months and higher in other months of the growing season. In contrast, the PWPC was higher in hot months and lower in other months of the growing season. The correlation coefficient between the PWPC and the soil water potential was - 0.87. It is concluded that PWPC would reflect the influence of environment on plant and its response to environment.