Determination of Soil Moisture Content at Permanent Wilting for Us in Field Studies

In ecological investigations of interactions between plants and soil moisture, whether the aim is to determine fundamental plant-environment relationships or primarily to solve immediate plant production problems, the soil moisture content at permanent wilting, expressed as a percentage of the dry weight, is a basic determination. Although there is evidence that this soil moisture value may not represent the exact non-available moisture content of the soil (4, 8) it is generally agreed that it represents the limit of favorable plant growth conditions and will be considered here as non-available soil moisture