Investigation of terminal irrigation effect on yield and yield components of ten barley (Hordeum vulgare L.) cultivars in Karaj

Nowadays using suitable barley cultivars under drought stress is important for increasing
economical yield. In order to study of the terminal irrigation (at ear appearance) effect on
yield and yield components of 10 barley cultivars in field condition¡ an experiment was
conducted in field research stations of Islamic Azad Universities of Karaj during 2010-
11. This experiment was carried out in form of split plot based on randomized complete
block design with four replications. Main plots comprise of two different irrigation
regimes: full irrigation (I1) and drought stress (terminal irrigation at ear appearance) (I2)
also sub plot includes 10 barley cultivars (Valfajr¡ Rihan¡ Kavir¡ Zarjo¡ Goharjo¡ Karoon¡
Dasht¡ Torkeman¡ Nosrat and Yusof). According to obtained results drought stress caused
significant decreasing on grain yield¡ total dry weight¡ 1000 grain weight¡ ear number per
unit area¡ grain weight per ear¡ plant height and peduncle length and harvest index was
not affected by drought stress. Highest grain yield obtained in full irrigation condition
relevant to Kavir (7781.5 kg/ha) and Nosrat (7414.8 kg/ha) cultivars also Goharjo cv. in
both full irrigation and drought condition grain yield was 2685.2 and 1962.8 kg/ha¡
respectively. Also Kavir cv. with reduction 46.36% and Dasht cv. with reduction 2.34%
of grain yield¡ showed highest and lowest sensitivity to drought¡ respectively. Grain yield
showed positive correlation to some traits such as 1000 grain weight¡ ear number per unit
area¡ harvest index¡ plant height and peduncle length.