Characterising resilience and resource-use efficiency traits from Scots Bere and additional landraces for development of stress tolerant barley (PhD)

Abstract

With a growing population, it is important to increase crop yield. However, there is a low priority in breeding for increased tolerance to low input or marginal environments.

Potential sources of viable resilience and resource-use efficiency traits are landraces local to areas of marginal land, such as the Scots Bere from the Highlands and Islands of Scotland.

Bere barley is a deeply historically rooted landrace of barley that has been grown on predominately marginal land for the last half millennia. The landrace yields well in these conditions.

The project aim was to assess and genetically characterise traits associated with enhanced resistance/tolerance, and to identify contributing genomic regions.

The JHI spring barley collection, consisting of a number of Bere lines, was screened for biotic stress resistance to Rhynchosporium commune and abiotic stress resistance to the conditions of manganese (Mn) deficiency and salt stress. Additionally, the interaction of these stresses was assessed.

The results identified Bere lines that show an increased resistance/tolerance to each of the three stresses, compared to elite cultivars.

The Bere population, as a whole, showed an inherent enhanced Mn-use efficiency, correlating to increased accumulation of Mn in the shoots.

These results suggest that Bere landraces have unique abilities to cope with stress.

Interaction studies revealed complex line-specific interactions, along with an overall adverse effect of salt on rhynchosporium symptoms.

Several genomic regions for Mn-use efficiency, salt tolerance, and rhynchosporium resistance traits, originating from the Bere lines, were identified, along with potential candidate genes.

Further examination and validation of these regions should be undertaken for breeding for marginal lands. By introgression into elite cultivar backgrounds, they may contribute biotic and abiotic stress-tolerance genes. This could create novel cultivars to efficiently and resiliently yield under low input and marginal environments.