Quantitative and qualitative indices of spring rapeseed cultivars affected by irrigation intervals and nitrogen splitting in Shahryar region

To study the effects of irrigation intervals and nitrogen splitting on some quantitative and quatitative indices of spring rapeseed cultivars، an experiement was conducted in spring of 2007 at research farm of College of Agariculture، Islamic Azad Universitty، Shahr-e Qds Branch، Shahryar، Iran. Experimental design was a split-plot factorial based on completely randomized block design with three replications. The main plot factors were irrigation intervals (6،13 and 20 days) and canola cultivars (Hyola 308 and Hyola 401)، and nitrogen splitting (100:0)، (25:75)، (50:50) and (0:100) were sub plot with a factorial arrangement. Results showed that seed yield significantly reduced by increasing the irrigation intervals. The highest seed yield (1012. 4 kgha-1) was obtained in 6 days intervalirrigation from Hayola 401. Nitrogen splitting in days interval irrigation also produced the highest seed yield. Although 1000 seed weight of Hyola 308 was more than Hyola 401، but differences of seed yield were not significant which can be related to pod shattering or harvesting method. The effect of irrigation intervals was not significant on oil percent، but the oil content of Hayola 401 (31. 8%) was more than that of Hayola 308 (28. 7%).