Evaluation of Drought Stress Indices in Canola under Deficit Drip Irrigation

An experiment was conducted to evaluate drought stress indices in a deficit drip irrigation system on yield and grain yield components, oil yield, seed oil percentage and water use efficiency of canola in two years of cultivation (2010-2011 and 2011-20120 at Behbahan Agricultural Research Station. The experiment was carried out as split plots in randomized complete block design with 4 replications. The main factor included water content in drip irrigation in four levels of 50, 75, 100 and 125% of crop water requirement and a sub factor including Hyola 401 hybrid and RGS003 cultivar. The comparison of the mean grain yield for irrigation and cultivar interactions showed that Hyola 401 at 100% water requirement with 3161.2 kg ha-1 yield was superior related to 125% water requirement due to less water consumption. The averages water consumption of the 2-years experiment were 1958.8, 2938.1, 3902.6 and 4896.9 m3/ha in 50, 75, 100 and 125% treatments, respectively. The results of Pearson correlation coefficient indicated by increasing the weight of 1000 seeds, the grain yield and seed oil yields are increased and the water use efficiency is reduced. The low values of SSI and TOL indices and also the higher values of STI, MP and GMP indices in Hyola hybrids compared to RGS003 cultivars introduced Hyola 401 hybrid as a superior treatment in terms of drought stress. The identical trend of changes in STI, MP and GMP indices in 50 and 75% water stress treatments caused these indices to be suitable for introducing drought resistant treatments.