Canola Seeding Rate and Cultivar Hybrid Influence on Spring Canola Performance in North Dakoa.

Spring canola has become a viable economic alternative for many producers in North Dakota.  Previous research conducted on seeding rates in North Dakota focused on open pollinated and hybrid non- herbicide tolerant lines.  Advances in canola breeding have lead producers to favor seeding herbicide tolerant Roundup Ready (RR) and Liberty Link (LL) hybrids.  Rising seed prices have resulted in producer consideration of lower seeding rates to reduce costs.  This field study examined the effects of seeding rates on yield and agronomic traits of a RR and LL canola hybrid.  The initial 2013 study was conducted at Langdon in a randomized complete block design in a split plot arrangement with hybrids as main plots and seeding rates as subplots.   Seeding rates were 3, 6, 9, 12, and 15 pure live seed (PLS) ft^-1. Plant emergence was excellent for all seeding rates. No significant interactions between hybrid and seeding rate for any of the traits were observed.  Significant differences between hybrids only occurred for plant height, lodging and percent oil.  Increasing seeding rates resulted in more rapid total ground cover.  Yield increased with higher seeding rates.  The 3 PLS ft^-1 seeding rate yielded significantly less than the 9, 12, or 15 PLS ft^-1 seeding rates while the 6, 9, and 12 PLS ft^-1 seeding rates were not significantly different from one another.  Although there was no significant difference in net return a^-1 (net return=grain value-seed cost), the optimum occurred at a seeding rate of 12 PLS ft^-1 which was $63 and 21 a^-1 higher compared to the 3 and 6 PLS ft^-1 seeding rate, respectively, which would be an important consideration for producers.   Results from the 2014 Langdon and Minot trial locations also will be reported.