Mapping of a covered smut resistance gene in barley (Hordeum vulgare)

Abstract

Covered smut of barley, caused by Ustilago hordei, is a seed-borne disease. Economic loss is due to decreased yield and to contamination of healthy grains with black teliospores. Molecular marker-assisted selection for covered smut is desirable, because traditional screening in the greenhouse and field is time consuming, expensive, and unreliable. The randomly amplified polymorphic DNA (RAPD) marker OPJ10₄₅₀, tightly linked to covered smut resistance in the barley line Q21861, was mapped to the short arm of chromosome 5 (1H) near the restrict fragment length polymorphic marker Act8A in the 'Harrington'/TR306 mapping population. The covered smut resistance gene in Q21861 was given the provisional designation of Ruhq. Sequence tagged site marker aHor2 and RAPD marker OPO6₇₈₀ on the short arm of chromosome 5 (1H) were closely linked to Ruhq. The amplified fragment length polymorphic marker E-AAA/M-CCC₂₆₅ was also linked to Ruhq. These markers will be useful for marker-assisted selection for covered smut resistance in barley.

Keywords:

• disease resistance
• marker-assisted selection (MAS)
• molecular mapping