Key Points
- The Crop Sequence project was set up to examine the influence of five spring sown break crops on the performance of following wheat crops. Arable Extra No.72 carried the yield data from the trial.
- The five break crops produced large differences in the gross margins of the two following wheat crops.
- Take-all (Gaeumannomyces graminis var. tritici (Ggt)) was implicated in a number of the yield differences and as a consequence second wheat margins were considerably lower than first wheat margins.
- First wheat, following spring sown barley and ryegrass (no clover content), gave inferior gross margins to first wheat established after brassica seed crops, linseed and peas.
- There was evidence that whilst the first wheat margin following short term ryegrass (2 years) was inferior, second wheat margins following ryegrass were often superior to arable break crops, such as peas.
- Overall, this tended to even up the 2 year margins for wheat following short term grass compared to wheats following brassica or peas. However, the loss in the productivity of the first wheat (after grass) tended to have a greater influence on overall two year margins than the gain in the second wheat.
- Since many growers would not consider second wheat production, the slightly lower productivity of first wheat following short term grass could be a significant fact emerging from the trial.
- Spring sown barley did not constitute an effective break crop, giving rise to significantly lower gross margins in following wheat crops.
- Soil quality measurements revealed that whilst the five spring crops produced small differences in soil quality, these differences were not carried over to subsequent years (through the following two wheat).