In order to study the effect of limited-irrigation stress on canola cultivars, an experiment was conducted in 2007-2008 at the Safiabad agricultural research center. The design was a split plot in a completely randomized block basis with three replications. Main plots were consisted of 4 levels of limited-irrigation, irrigation based on 60 mm cumulative evaporation (Control), withholding irrigation in flowering stage, withholding irrigation in pod initiation and irrigation withholding in grain filling period, and subplots were 5 canola cultivars (Hyola308, Hyola330, Hyola401, Hyola420 and RGS003). The mean comparison of interaction showed that the highest (3155.55 kg.ha-1) grain yield appointed to Hyola420 cultivar in optimum irrigation (control treatment), and the lowest (1491.66 kg.ha-1) belonged to RGS003 cultivar at withholding irrigation in pod initiation period. The maximum (161.42) number of pods observed on Hyola330 cultivar at optimum irrigation (irrigation after 60 mm cumulative evaporation), and the minimum (78.1) ones appointed to RGS003 cultivar at withholding irrigation in pod initiation period. Results showed that there was no significant difference among withholding irrigation, cultivars and the interaction effect of them for oil content. By considering the results of this experiment, withholding irrigation at flowering, pod initiation and grain filling periods leads to decrease grain yield by 24.72%, 14.33% and 11%, respectively. Reduction of grain yield due to the withholding irrigation during flowering, podding and grain filling stages was along with a decrease in the number of pods per plant and thousand seed weight. By considering the results of experiment, withholding irrigation in flowering stage has to be avoided.
Kalantar Ahmadi S A, Shirani rad A H, Siadat S A. Study of limited-irrigation stress on grain yield of canola cultivars in north Khouzestan conditions. 3 2015; 1 (2) :53-65 URL: http://yujs.yu.ac.ir/jopp/article-1-36-en.html