**3.2 Crop factors that affecting ET**

Crop factors such as crop species, radiation reflection coefficient, leaf area index (LAI) in different growth stages of the plant, plant height and root depth (depth of the radicular system) are influenced on the crop ET, which are described details as follows:

### *3.2.1 Crop species*

This factor is related to the foliar architecture (spatial distribution of the leaves), internal resistance of the plant to water transport, and other morphological aspects (number, size, and distribution of stomata, etc.), which exert a direct influence on ET [13, 16].
