Investigation into the specific weight differences between wheat varieties tested in the HGCA Recommended List and commercially-grown crops from 2007–2012

Abstract

Wheat quality suffered greatly during the 2011/2012 season and many growers failed to achieve the required specifications for their end-user requirements. This resulted in growers becoming financially penalised and the UK export market struggling to compete globally. This study compared quality information from HGCA Recommended List trials and from commercial grain samples taken between 2007 and 2012. The aims were to integrate variety quality data collected from these two sources in order to investigate quality differences between varieties tested in the RL and those crops grown commercially and to identify factors which may account for variable specific weight measurements between seasons. Specific objectives included:
1. To examine Recommended List (RL) and Cereal Quality Survey specific weight quality data within region and year to assess the quality potential that can be achieved.
2. To identify factors which may have influenced the fluctuation in specific weight quality in each region and year.

Analysis of both the commercial crop and those grown in an RL trial situation indicates that specific weight is variable between seasons and 2012 was an incredibly poor season in both the RL and the commercial crops, only achieving 71.9kg/hl and 69.6kg/hl respectively. Regional and seasonal differences were mirrored in the two sets of information and 2011 achieved the highest specific weights and 2012 the lowest in both sets of data. This suggests the RL data can be used to help the industry understand fluctuations in quality. The RL data does use higher inputs to manage disease and the drop in quality in 2012 was lower than that observed in commercial data, suggesting high fungicide inputs may have mitigated the loss in quality to a certain degree, but the major factor was the weather. Close investigation of the varieties shows later-maturing varieties tend to have higher yields but lower specific weights than early-maturing varieties. This pattern is seen over the last five years and not just in the poor quality year of 2012. Although yield is an important driver in the selection of new varieties, choosing early-maturing varieties to grow alongside later but potentially higher yielding varieties for a specific end use may mitigate losses in quality from specific weight which may be associated with high rainfall and low sunshine in the grain filling periods in June and July.