Organic and urea nitrogen fertilizer effects on rapeseed and wild mustard competition

The competitive effects of wild mustard on rapeseed with organic amendments and urea alone or combined were studied for 2 years. Treatments consisted of three Sinapis arvensis densities and fertilizer treatments of composted cattle manure, composted municipal waste, urea nitrogen, a combination CCM+urea, a combination of CMW+urea, and a control. Weed growth was stronger in urea fertilizer and with combined organic amendments than in organic amendments alone. However, application of organic amendments could increase weed competitive ability. In the first year, urea fertilizer alone and combined with organic amendments led to the greatest rapeseed yield, but in the following year, organic amendments alone were able to increase rapeseed yield approximately equal to urea fertilizer and combined with organic amendments. Application of organic amendments alone or combined with N fertilizer could be an efficient method to increase soil productivity.