Evaluation Some Agronomical Traits of Canola Cultivars (Brassica napuse L.) Response to Spring Planting Date

Planting date is an important factor affecting crop yield and quality, especially in arid and semi-arid and cold regions. The production of oil grain in Iran is not high, about 80% of Iran's necessary oil is imported from foreign countries. Planting dates obviously affect canola yield and yield components. The objective of the study was to evaluate the effects of spring planting date on yield and yield components and grain oil yield and grain oil percent of three canola cultivars. Experiments were conducted in two growing seasons; 2010 to 2011 and 2011 to 2012 at the Agricultural Farm Station of Payame Noor University of Tiran, Isfahan, Iran. Experiment design study was according to split plot and randomized complete blocks in three replications. Spring planting date in three levels included: 24 February, 11 March, 25 March as main plots and cultivars included: Hybrid Reagent ×Cobra, Okapi and SLM046 as sub plots were considered. The results demonstrated that late planting date decreased yield and yield components and grain oil percent, grain oil of canola cultivars. In addition, Number of grain per pod, grain yield, grain oil yield was significant affected by late planting and there were dramatically decreased. Also, significant differences were found between planting times for most of the traits measured. In recent research, interaction between two factors of planting date× cultivars on grain yield, grain oil percent and grain oil was significant. At finally, Regent× Cobra cultivar not only had the highest grain yield (2050 kg.ha -1 ) and oil yield (555.5