Evaluation of resistance to Pseudoperonospora humuli and of the content of alpha acids and hop oils in hops of selected genetic resources of hop Humulus lupulus L.

Abstract

Twenty hop genotypes were selected for the evaluation of resistance to primary and secondary Pseudoperonospora humuli infection and of alpha acid and hop oil content in the hops. From the wild hop genotypes, two from Canada and one from Belgium showed resistance. Among the registered hop varieties, the Czech varieties Kazbek and Boomerang were the most resistant. Both wild hop genotypes from Canada showed the highest content of alpha acids among the wild hop entries, namely 4% w/w. The lowest variability of the alpha acid content in the wild hop category was found in two wild hop varieties from the Caucasus, one from Austria and one from Lithuania. The highest content of hop oils was determined in two hop genotypes from Canada and two from Belgium. Wild hop genotypes from the Caucasus have the lowest variability of hop oils among the wild hop entries. Two hop genotypes from Canada and one from Belgium were selected for breeding aimed at drought resistance.

Keywords

• hop downy mildew
• hop genotypes
• humulus lupulus l.
• primary and secondary infection
• resistance