Dataset Information

Genetic variation of biomass recalcitrance in a natural Salix viminalis (L.) population.

ABSTRACT:

Background

Salix spp. are high-productivity crops potentially used for lignocellulosic biofuels such as bioethanol. In general, pretreatment is needed to facilitate the enzymatic depolymerization process. Biomass resistance to degradation, i.e., biomass recalcitrance, is a trait which can be assessed by measuring the sugar released after combined pretreatment and enzymatic hydrolysis. We have examined genetic parameters of enzymatic sugar release and other traits related to biorefinery use in a population of 286 natural Salix viminalis clones. Furthermore, we have evaluated phenotypic and genetic correlations between these traits and performed a genomewide association mapping analysis using a set of 19,411 markers.

Results

Sugar release (glucose and xylose) after pretreatment and enzymatic saccharification proved highly variable with large genetic and phenotypic variations, and chip heritability estimates (h ²) of 0.23-0.29. Lignin syringyl/guaiacyl (S/G) ratio and wood density were the most heritable traits (h ²?=?0.42 and 0.59, respectively). Sugar release traits were positively correlated, phenotypically and genetically, with biomass yield and lignin S/G ratio. Association mapping revealed seven marker-trait associations below a suggestive significance threshold, including one marker associated with glucose release.

Conclusions

We identified lignin S/G ratio and shoot diameter as heritable traits that could be relatively easily evaluated by breeders, making them suitable proxy traits for developing low-recalcitrance varieties. One marker below the suggestive threshold for marker associations was identified for sugar release, meriting further investigation while also highlighting the difficulties in employing genomewide association mapping for complex traits.

SUBMITTER: Ohlsson JA

PROVIDER: S-EPMC6545741 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Publications

Genetic variation of biomass recalcitrance in a natural <i>Salix viminalis</i> (L.) population.

Ohlsson Jonas A JA Hallingbäck Henrik R HR Jebrane Mohamed M Harman-Ware Anne E AE Shollenberger Todd T Decker Stephen R SR Sandgren Mats M Rönnberg-Wästljung Ann-Christin AC

Biotechnology for biofuels 20190603

<h4>Background</h4><i>Salix</i> spp. are high-productivity crops potentially used for lignocellulosic biofuels such as bioethanol. In general, pretreatment is needed to facilitate the enzymatic depolymerization process. Biomass resistance to degradation, i.e., <i>biomass recalcitrance</i>, is a trait which can be assessed by measuring the sugar released after combined pretreatment and enzymatic hydrolysis. We have examined genetic parameters of enzymatic sugar release and other traits related to ...[more]

PMID: 31171936

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