Registration of ‘Clearwater’ Low‐Phytate Hulless Spring Barley

Abstract

‘Clearwater’ (Reg. No. CV‐335; PI 647080) is a spring two‐rowed barley ( Hordeum vulgare L.) developed by the USDA‐ARS and the Idaho Agricultural Experiment Station. Clearwater was selected and released on the basis of competitive agronomic performance in combination with low‐phytate (LP), hulless grain. Clearwater derives from an BC 1 F 3:4 selection from the cross ‘Baronesse’*2/Pmut640//HB317. It was tested under the experimental designation 01ID435H. The parent Pmut640 is a sodium‐azide generated mutant induced in the two‐rowed malting cultivar Harrington. The mutation conferring reduced phytate in Pmut640 is believed to be allelic to lpa2‐1 , which results in a reduction of phytate ( myo‐ inositol 1,2,3,4,5,6‐hexa kis phosphate) of approximately 40 to 50% and an increase in inorganic P of greater than 400%. Studies have shown that these changes are associated with increased feed quality and reduced environmental impacts when fed to non‐ruminant animals, based on increased P digestibility and reduced fecal P content.