Submitted to: Journal of the American Society of Brewing Chemists
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/5/1997
Publication Date: N/A
Interpretive Summary: Much information on hop (Humulus lupulus L.) production and maintenance exists but little is known on the genetics of quality characteristics. Furthermore, even less is known about the influence male parents have upon female offspring. Genetic information would help breeders in determining efficient breeding and selection protocols. In this study, quantitative genetic parameters for yield, alpha-acid levels, beta-acid levels, cohumulone levels, and hop storage index in male hop plants were estimated. Based upon the data, selection for all traits should be possible with greatest response observed for beta-acid and cohumulone levels. However, negative genetic correlation between alpha-acid levels and beta-acid levels could potentially cause difficulties when practicing simultaneous selection for both traits. This information will prove valuable to hop breeders worldwide as the USDA male germplasm is used extensively in breeding programs.
Technical Abstract: The objective of this study was to determine general combining ability (GCA) and genetic correlations for five traits in male hop (Humulus lupulus L.) accessions. The analysis was performed with 14 females nested in 6 males. We observed significant (P < 0.05) GCA for all traits. Significant positive genetic correlations were observed between COH and yield and between COH and HSI. Significant negative genetic correlations were observed between alpha- and beta- acid levels and between beta-acid levels and HSI. The results provide information for breeders on choice of males for specific traits and a selection protocol guide for multiple trait selection.