ESTIMATES OF HERITABILITY AND GENETIC CORRELATION FOR 5 TRAITS IN FEMALE HOP ACCESSIONS

Little has been published on the heritability of traits in hop (Humulu s lupulus). What has been published does not provide adequate informat ion for the determination of selection protocol. This article is the f irst to report narrow sense heritabilities and genetic correlations fo r economic traits in female hop plants. Seven female and 14 male acces sions were crossed using a North Carolina Mating Design I. At least tw o offspring per cross were analyzed in three replicates for the determ ination of genetic parameters. Data were collected on yield, alpha-aci ds, beta-acids, hop storage index (HSI), and essential oil content. Si gnificant differences (P less than or equal to 0.05) among maternal fa milies were observed for all five traits. USDA female accessions 56013 (1,985.28 kg/ha) and 56009 (2117.28 kg/ha) produced offspring with hi ghest average yield. Maternal lines 21055 and 21254 produced families with the highest average alpha-acids content, while 65009 produced off spring with the highest average content of beta-acids. Maternal famili es derived from 21522, 56013, and 65009 all had more desirable HSI val ues than did the other families. Finally, 21055, 62013, and 65009 prod uced offspring possessing the highest average content of essential oil s of the maternal lines. Narrow sense heritability values were highest for alpha-acids (h(2) = 0.88 +/- 0.17), moderate for beta-acids conte nt (h(2) = 0.35 +/- 0.02) and HSI (h(2) = 0.31 +/- 6.1 x 10(-6)), and low for essential oil content (h(2) = 0.12 +/- 5.3 x 10(-4)). Heritabi lity value for yield was more difficult to ascertain significance due to the high standard error associated with the estimate (h(2) = 0.20 /- 1,463). Significant negative genetic correlations were estimated be tween alpha-acids and beta-acids (r = 0.42), alpha-acids and yield (r = -0.66), HSI and yield (r = -0.63), and essential oil content and yie ld (r = -0.38). Significant positive genetic correlations observed wer e for beta-acids with yield (r = 0.84), HSI with alpha-acids (r = 0.28 ), and essential oil content and alpha-acids (r = 0.43). The informati on obtained from this research should enable hop breeders to make info rmed decisions regarding breeding protocol for these five economic tra its.