Ebrahim Nohani - Department of water engineering and hydraulic structures, Dezful Branch, Islamic Azad University, Dezful, Iran.
Saeed Taheri Ghannad - Department of water engineering, Dezful Branch, Islamic Azad University, Dezful, Iran.

In conventional methods of irrigation, the water availability in the soil is used as a measure of water stress in plant organs, but the water status in these organs is not measured directly. For accurate planning of irrigation, the new methods try to directly measure the water status (content) of theplant aerial organs instead of soil water content. For this reason, during the last three decades, the use of leaf water potential and canopy temperature asindicators of water stress and irrigation scheduling have come to the researchers focus of attention. In this study, meanwhile introducing andevaluation the advantages and disadvantages of them, a multivariate model based on meteorological parameters such as wind speed, air humidity, solarradiation, air temperature and plant surface temperature were defined. Using the model, the irrigation scheduling can be adjusted based on direct measurements in the fields in such a way that the stress to the plant would not exceed the allowable maximum level

Irrigation time, Plant water stress, Irrigation scheduling