Finding a recipe for high wheat yields

This year AHDB Cereals & Oilseeds became a sponsor of the Yield Enhancement Network (YEN) which held its annual awards event in November. The aims of the YEN are to identify and support arable innovators through an annual competition – in which members compete to establish new yield records, through analysis of results and networking. In addition, the competition aims to find yields that are as close as possible to their potential.

Plant breeders have given us modern varieties with genes for very high yield but most crops never achieve anywhere near the yields they are capable of. The YEN recognises this. Its ambition is to bridge the gap between what the best growers are doing and the so-called “bio-physical potential” yield for cereals. The best YEN yield in 2015, at 16.5 t/ha, achieved 79% of potential. The highest percentage of potential yield attained was 81% for a crop that yielded 14.1 t/ha.

Where do these potential yield figures come from? ADAS scientists have developed a method to work out it out, and Pete Berry recently presented an analysis of some of the findings to the Farmers Association at High Mowthorpe. As you might expect, the calculation is based on how much of the available sunlight and water the crop can take in. No surprises there.

Also not surprising is the heavy dependence of actual yields on the weather from spring onwards. In a nutshell, March and April 2015 were relatively dry in the north which led to good tiller production and retention. Also the extra sunlight in April resulted in more grains setting. The cool summer months led to increased grain filling so that yields of these late-maturing crops were generally well above average. Another important factor, conditions early in the season were favorable enough to allow timely spraying and this resulted in low disease and lodging pressure.

Clearly we can’t do anything about the weather but the YEN results have identified other opportunities for influencing yields. The data show that the factor having the greatest effect was the overall size of the crop – the bigger the biomass, the higher the yield. Even the straw yield alone correlates with yield. The implication of this is that newer varieties, which have high biomass, are likely to need different management techniques.

YEN regional meetings will be run by AHDB Cereals & Oilseeds in the late spring. The meeting for the North region will be on 12 May near York. For more information about the initiative, have a look at the website