Abstract:
In order to estimate the water
requirement of barley and wheat by using of
ET-HS model, a research was conducted at
Research Farm of Islamic Azad University,
Isfahan (Khorasgan) Branch, Iran. ET-HS
model is used to determine irrigation water
quantity and irrigation schedule for different
crop. The study was based on randomized
complete block design (RCBD) with three
replications and six treatments. The
irrigation treatments included irrigation to
supply 50, 75, 100, 125 and 150% of crop
water demand on the basis of ET-HS model
during growing season and control
treatment (conventional irrigation), which
was irrigation on the basis of 70 mm
evaporation from Class A evaporation pan
during growing season. In barley
experiment, the highest values for number
of fertile tiller, maximum LAI, total dry
matter in maximum LAI stage, number of
grain per spike, a thousand seed weight
(35.56 g), grain yield (7877.9 kg/ha),
biological yield (17689.7 kg/ha) and harvest
index (44.45%) was obtained for irrigation
according to 100% of crop water demand on
the basis of ET-HS model. In wheat
experiment, the highest number of fertile
spike, number of grain per spike, 1000 grain
weight, grain yield, biological yield was
obtained for irrigation treatment on the basis
of 100% ET-HS model; moreover, the
maximum harvest index was related to
control treatment, followed by irrigation on
the basis of 100% of ET-HS model.
Conclusively, the appropriate irrigation
treatment was 100% of crop water demand
on the basis of ET-HS model during the
growth season for both crops.
