Association genetics in Corymbia citriodora subsp. variegata identifies single nucleotide polymorphisms affecting wood growth and cellulosic pulp yield.
Wood is an important biological resource which contributes to nutrient and hydrology cycles through ecosystems, and provides structural support at the plant level. Thousands of genes are involved in wood development, yet their effects on phenotype are not well understood. We have exploited the low genomic linkage disequilibrium (LD) and abundant phenotypic variation of forest trees to explore allelic diversity underlying wood traits in an association study. Candidate gene allelic diversity was modelled against quantitative variation to identify SNPs influencing wood properties, growth and disease resistance across three populations of Corymbia citriodora subsp. variegata, a forest tree of eastern Australia. Nine single nucleotide polymorphism (SNP) associations from six genes were identified in a discovery population (833 individuals). Associations were subsequently tested in two smaller populations (130-160 individuals), 'validating' our findings in three cases for actin 7 (ACT7) and COP1 interacting protein 7 (CIP7). The results imply a functional role for these genes in mediating wood chemical composition and growth, respectively. A flip in the effect of ACT7 on pulp yield between populations suggests gene by environment interactions are at play. Existing evidence of gene function lends strength to the observed associations, and in the case of CIP7 supports a role in cortical photosynthesis.
CSIRO Plant Industry, GPO Box 1600 Canberra, ACT 2601, Australia.
Shannon K
SK
Dillon
CSIRO Plant Industry, 306 Carmody Road, St Lucia, QLD 4067, Australia.
Jeremy T
JT
Brawner
CSIRO Plant Industry, 306 Carmody Road, St Lucia, QLD 4067, Australia.|University of the Sunshine Coast Faculty of Science, Health, Education and Engineering, Maroochydore, QLD 4558, Australia.
Roger
R
Meder
University of the Sunshine Coast Faculty of Science, Health, Education and Engineering, Maroochydore, QLD 4558, Australia.|Department of Employment Economic Development and Innovation, 1 Cartwright Road, Gympie, QLD 4570, Australia.
David J
DJ
Lee
CSIRO Plant Industry, GPO Box 1600 Canberra, ACT 2601, Australia.
Simon G
SG
Southerton
D008841:Actin Cytoskeleton / Q000737:chemistry / Q000235:genetics; D000483:Alleles; D002482:Cellulose / Q000737:chemistry* / Q000235:genetics; D017343:Genes, Plant; D056726:Genetic Association Studies; D015810:Linkage Disequilibrium; D027822:Myrtaceae / Q000737:chemistry* / Q000235:genetics* / Q000254:growth & development; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics; D010641:Phenotype; D010788:Photosynthesis; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics; D020641:Polymorphism, Single Nucleotide; D014934:Wood / Q000737:chemistry / Q000235:genetics / Q000254:growth & development*
D009687:Nuclear Proteins; D010940:Plant Proteins; D002482:Cellulose