Responses of Canola Morphological and Agronomic ‎Characteristics to Potassium Sulfate Fertilization under ‎Drought Stress

Abstract

ABSTRACT In order to reduce the damage caused by late-season drought stress of canola, a factorial split plot experiment was performed on the basis of the randomized complete blocks design with three replications in Karaj, Iran. The treatments were Potassium sulfate in two levels, including application and non-application of potassium sulfate, irrigation at three levels including normal irrigation (control), restricted irrigation from the flowering and pod formation stage, as factorial were in main plots and winter canola cultivars including Opera, L72, KR1, GKH3705, GKH0224 were in subplots. The interaction effect of potassium sulfate × irrigation × cultivar on plant height, number of pods per the main stem, number of pods per branch, number of pods per plant, seed yield, and seed oil yield was significant at the 1% level. In conditions of applying potassium sulfate and irrigation interruption from the flowering stage, Opera cultivar had the highest seed yield with a mean of 3715 kg ha−1. In conditions of not applying potassium sulfate and under normal irrigation (control), the promising line of L72 with a mean of 6169 kg ha−1, and in the late season drought stress (irrigation interruption from the pod formation and flowering stages), the opera cultivar with the means of 4763 and 3468 kg ha−1 had the highest seed yield.