Organic winter wheat: optimising planting

Summary

Data from the second year of experiments at three sites (Wakelyns in SE and Sheepdrove in SW England; and Chapel Farm in SE Scotland) to investigate the effects of interactions among a range of agronomic practices (row spacing, seed density, weeding and undersowing with clover) on winter wheat performance are presented, and compared with first year results. Trends seen at all years and sites indicate that narrow row drill arrangements with high seed rates result in the highest yields. This combination also performed well for emergence and establishment. The effect of drill arrangement was significant (P<0.05) at two of the three experimental sites with establishment of 282 and 232 plants m-2 at Sheepdrove and Chapel farm respectively. There were significant interactions between row spacing and seed density at all three sites. A new composite cross population integrated into the experiment has performed well for a number of traits including canopy cover and grain yield.