The Effect of Crop Establishment Systems On the Nitrogen Use Efficiency of Spring Barley In Ireland.

Spring barley for malt and feed production is grown on 156,000ha annually accounting for 40% of Ireland’s arable area. Ploughing to 200mm depth followed by a secondary cultivation combined with sowing is the normal establishment system used. While there has been an increased interest in shallow non-inversion minimum tillage (MT) establishment systems for winter sown crops, there has been very little research or practice of MT in spring barley. This study evaluated the effects of cultivation systems and nitrogen rate on the nitrogen uptake and grain yield of spring barley (cv. Wicket) grown on a medium textured clay loam.

 Field experiments were carried out in 2009 and 2010 in the south east of Ireland. A 4 x 5 factorial design using four establishment systems (MT-Fall; MT-Fall+Spring; MT-Spring; Plough-Spring) and 5 N rates (0, 75, 105, 135, 165 kg/ha) with 5 replications was used. Crop N uptake (CNU) was measured throughout the growing season. Grain and straw N uptake, grain yield and grain protein were recorded at harvest. Statistical analysis was carried out by analysis of variance using the Genstat statistical package.

 In both years grain yields were moderate to low considering the normal yield potential at this location. The MT-Spring establishment method performed poorly in 2009 compared to the other establishment methods with a significantly lower CNU at GS 55 and 85, and reduced total N uptake and grain yield at harvest. The plough-based system achieved the highest total N uptake and grain yield. All four establishment systems performed similar in 2010 with no significant difference in total N uptake or grain yield.

 These experiments indicate that the performance of MT systems for spring barley establishment is season dependent and the plough-based system is the most reliable method of establishing spring barley in Ireland.