Managing Potential Allelopathic Effects of Winter Wheat Residue in No-till Winter Canola Production.

Winter wheat is the prominent crop in Oklahoma production systems, with over 5 million acres planted annually. As a means to alleviate stagnant yields and poor quality wheat many producers around the state have moved to rotating winter wheat with winter canola. While the benefits of canola to the wheat production system have been well documented, recent anecdotal reports from have field have indicated a decline in emergence, early growth, and winter survival of winter canola when grown in a no-till rotation with winter wheat. Initial laboratory and greenhouse studies have suggested that 30% of wheat varieties grown in Oklahoma have a negative effect on winter canola growth and development. Additionally, first year results in-field, have suggested that similar decreases in early season growth from the laboratory were found in-field. These results demonstrate that this is a facet of production that will need to be managed in order to maintain a productive and sustainable production system.