The impact planting season on the yield formation and yield components of spring cultivars of rapeseed under different moisture regimes

In order to study the impact planting season and moisture stress on the yield formation and yield components of spring cultivars of rapeseed an experimental field was performed during 2008-2009 in Qazvin research station، Iran. It was performed in form of Split-plot factorial based on RBD with three replications. The main factor was considered as the growing season condition in two levels including the autumn planting (10/02/2008) season and spring planting (03/02/2009) season. Irrigation was performed at two levels including usual irrigation as control and stop of irrigation when flowering stage onwards and four cultivars consist of RGS003، Sarigol، Hyola401 and Option500 were selected as subplots. In order to calculate traits such as main and sub pod length، the number of grain in main and sub- pod and yield formation. After sampling from different stages of growth parameters measurement، the results showed that tested traits due to field management operations such as growing season and moisture stress are corrected. Results showed that the simple effect of planting and irrigation season on the main and sub-pod length، number of grain in main and sub-pod and grain yield became meaningful and the interaction effect of planting and irrigation season on the main and sub-pod length، and the number of gain in main pod did not be meaningful but on grain number and grain yield in sub pod was meaning. Thus with increasing pod length and number of grain in main and sub pod، grain yield will be increased too.