3.1. Planting density effect on evapotranspiration and crop
coefficient
The daily average ETc calculated for each of the 7 to 15-day
intervals increased linearly as Rs (ETc = 0.24Rs −
0.53, R2 = 0.88),
Ta (ETc = 0.24 Ta −
2.43, R2 = 0.76), and VPD (ETc = 2.19 VPD + 0.21,
R2 = 0.56) increased based on the pooled data from all treatments.
The daily average ETc was significantly influenced by Rs, Ta and
VPD (P < 0.001), and the correlation between the daily average ETc
and Rs was higher than those for Ta and VPD. Similar relationships
between the daily average ETc and Rs, Ta and VPD were observed
under different planting densities.