Phenotype screening tests for grain skinning

Barley grains have an adherent outer husk. An intact husk is an important characteristic of grain quality in malting barley, as it protects the underlying caryopsis and plays a key role in water uptake and germination during the malting process. An undesirable condition called grain skinning occurs when the husk becomes partially or wholly detached from the outer layer of the caryopsis, the pericarp. This physical defect causes serious inefficiencies during the malting process. The development of phenotype screening tests to differentiate susceptible and resistant varieties is a key objective of the BBSRC CIRC project on Causes and Control of Grain Skinning in Malting Barley (BB/J019623/1). Methods are being developed to quantify varietal differences under field and glasshouse environments. Growth conditions that mimic high skinning years, and potentially influence a lipid cementing layer (Gaines et al. 1985) between the husk and pericarp are being trialled, coupled with post-harvest mechanical treatments of grains to further induce skinning.