Evaluation of winter canola genotypes response to terminal drought stress under application of ammonium sulfate

In order to study the effect of terminal drought stress on agronomic and qualitative traits of canola genotypes in the application of ammonium sulfate condition, an experiment was performed during two years of 2015-2016 and 2016-2017. This study was conducted as a factorial split-plot design based on completely randomized block design with three replicates at the research farm of the Seed and Plant Improvement Institute (SPII). At the pod formation stage, irrigation factors were included two levels, normal and restricted, and at the elongation stage, ammonium sulfate was included two levels of 0 and 150 kg per hectare, as factorial was set in the main plots and cultivars including BAL111, BAL119, BAL121, BAL128, and Nima were set in subplots. The results showed that among the genotypes examined, line BAL128 had the highest grain yield (3904 kg/ha), which increased 28% compared with the control treatment. The highest amount of grain oil (45.53 percent) was obtained in the second year of experiment and under normal irrigation conditions. By application of ammonium sulfate, the amount of oil increased by 2.5 percent in comparison with normal condition. The BAL128 line had the highest percentage of grain oil (44.29%). in normal irrigation condition, the use of ammonium sulfate resulted in decreasing the amount of glucosinolate to 22.88%. However, in restricted irrigation condition, the amount of glucosinolate decreased to 17.25 percent. In the irrigation and fertilizer treatments of this experiment, among the lines studied, The BAL128 line is recommended for similar experimental conditions.