Quantitative genetic parameters for yield, plant growth and cone chemical traits in hop (Humulus lupulus L.)

Abstract

BackgroundMost traits targeted in the genetic improvement of hop are quantitative in nature. Improvement based on selection of these traits requires a comprehensive understanding of their inheritance. This study estimated quantitative genetic parameters for 20 traits related to three key objectives for the genetic improvement of hop: cone chemistry, cone yield and agronomic characteristics.ResultsSignificant heritable genetic variation was identified for α-acid and β-acid, as well as their components and relative proportions. Estimates of narrow-sense heritability for these traits (h 2 = 0.15 to 0.29) were lower than those reported in previous hop studies, but were based on a broader suite of families (108 from European, North American and hybrid origins). Narrow-sense heritabilities are reported for hop growth traits for the first time (h 2 = 0.04 to 0.20), relating to important agronomic characteristics such as emergence, height and lateral morphology. Cone chemistry and growth traits were significantly genetically correlated, such that families with more vigorous vegetative growth were associated with lower α-acid and β-acid levels. This trend may reflect the underlying population structure of founder genotypes (European and North American origins) as well as past selection in the Australian environment. Although male and female hop plants are thought to be indistinguishable until flowering, sex was found to influence variation in many growth traits, with male and female plants displaying differences in vegetative morphology from emergence to cone maturity.ConclusionsThis study reveals important insights into the genetic control of quantitative hop traits. The information gained will provide hop breeders with a greater understanding of the additive genetic factors which affect selection of cone chemistry, yield and agronomic characteristics in hop, aiding in the future development of improved cultivars.

3D Molecular Cytology of Hop (Humulus lupulus) Meiotic Chromosomes Reveals Non-disomic Pairing and Segregation, Aneuploidy, and Genomic Structural Variation

“…Recent genetic, genomic, and quantitative trait analyses have demonstrated that the genome of hop is complex and structurally diverse (Zhang et al, 2017 ). Irregularities in hop transmission genetics are reflected in non-Mendelian segregation distortion and sex ratio bias (Seefelder et al, 2000 ; Jakse et al, 2008 , 2011 ; McAdam et al, 2013 , 2014 ).…”

Genomic approaches to selection in outcrossing perennials: focus on essential oil crops

“…Indeed this has been the case for various essential oil crops over the past decades. For example, five cycles of recurrent selection in Cymbopogon flexuosus (Lemongrass) increased mean oil concentration from 0.7 to 1.7 % (Kulkarni et al 2003), Barton et al (1991) H. lupulus Hop 0.37 0.03 Murakami (1999), McAdam et al (2014) while in Carum carvi (Annual Caraway) mean oil concentration increased from 3.4 to 7.4 % over 20 years of recurrent selection (Pank 2010). The Australian Tea Tree breeding program has doubled commercial Tea Tree oil yield from 150 to 300 kg ha −1 since 1993 through selection based on a weighted multi-trait index (Baker et al 2014).…”

Caracterização E Qualidade De Frutos De Cajarana (Spondias Dulcis Parkinson) Provenientes Do Oeste Da Bahia

“…A produtividade e a composição química de uma cultura é definida pela interação O desempenho no cultivo do lúpulo, é dependente principalmente de aspectos como produção de cones por planta, juntamente as características químicas da produção de resinas, contendo alfa e beta ácidos que conferem o amargor e aroma a cerveja (HIERONYMUS, 2012). Os teores de alfa e beta ácidos podem variar de plantas da mesma variedade com idade diferente e entre locais de plantio distintos, demostrando ser um caráter de origem complexa, de baixa herdabilidade e sofrendo alta influência do ambiente (MCADAM et al, 2014 chegou a uma definição oficial sobre seu significado:…”