Looking for grain skinning resistance in barleys
Scottish research is looking to find the barley varieties most resistant to grain skinning, which is an increasing problem for the nation’s £286m barley crop.
Grain skinning shows up when the husk that coats the barley grain becomes weak and then detaches, and this can lead to malting barley being downgraded to cheaper feed grain.
With an increasing amount of Scottish malting barley heading for the expanding Scotch whisky industry, barley deliveries with grain skinning are often rejected.
Scotland’s Rural College (SRUC) is leading the research and will look for varieties particularly resistant or susceptible, and also examine a wider range of likely contributing factors.
“Often farms only grow two or three varieties of barley and so if they suffer from grain skinning it could mean a large amount of their crop rejected,” says Steve Hoad, who leads SRUC’s agronomy, physiology and genetics team.
Varietal differences and weather conditions are likely to be key factors leading to the rejection of malting barley and thus a cut in the grower’s return.
Teams from the SRUC and Scotland’s James Hutton Institute will test barley varieties and identify in which ones the husk is most firmly attached to the grain.
One theory is that the quality of the natural glue that holds the husk to the grain in barley can vary between varieties.
Weather can also be a factor, with long drawn out harvest seasons appearing to make the problem worse, while grain skinning is seen less in dry summers.
“During prolonged wet conditions farmers can only harvest small amounts at once. This delay often means that grain skinning is more or a problem,” says Dr Hoad.
The concern is that with a changing world climate, Scotland could find that weather conditions continue to be very unreliable, such as in the run of recent bad summers.
The team will look to study hundreds of barley varieties looking for genetic markers for poor and good resistance, and it hopes to identify ones that will hold fast against grain skinning.
Risks for spring barley seed
Spring barley may suffer poor emergence this season, with the high level of diseases such as microdochium nivale and fusarium making seed testing more important.
These disease levels are high due to last year’s wet harvest, and drilling seed this spring into cold and wet soils will increase the possibility of emergence problems, warns the HGCA.
Where germination levels are acceptable, at above 85%, but microdochium is present, seed treatment will provide effective control, although the HGCA warns seed with poor germination will not be improved with a seed treatment.
However, if disease levels are above 70%, it is best to look for another seed stock, the HGCA says.
For growers with certified seed left over from last year it is important that this is checked for germination before using this spring.
The HGCA advises that drilling should be delayed until the weather improves, as sowing slightly later into good seed-beds rather than drilling in cold and wet conditions is likely to lead to better crop establishment.
