The study combined phenotypic evaluation, quantitative genetic analysis, and genome-wide association mapping in a panel of 100 rubber tree genotypes that included commercial clones and controlled-cross progenies. A total of 300 sampled trees were evaluated in a 10 × 10 triple-lattice design. Researchers measured wood density, moisture content, modulus of rupture, modulus of elasticity, compressive strength, lignocellulosic composition, proximate characteristics, and elemental composition, then analyzed these traits alongside 24,242 high-quality DArTSeq single-nucleotide polymorphism markers.

Rubberwood obtained when plantations are replanted is an increasingly important renewable resource for timber, furniture, and biomass-based industries in Southeast Asia, but the genetic architecture underlying its quality has largely remained unresolved. Substantial phenotypic variation was detected for most of the traits, particularly the mechanical properties and cell-wall components. Broad-sense heritability estimates ranged from 0 to 0.51, showing that the estimated genetic contribution varied markedly among characteristics.

Hemicellulose content, hydrogen content, and compressive strength parallel to the grain displayed moderate heritability, which the study identified as promising for association mapping and genetic improvement. Correlation analysis found biologically meaningful relationships among wood density, strength-related traits, and lignocellulosic composition. Using five complementary GWAS models—the generalized linear model, mixed linear model, constrained mixed linear model, FarmCPU, and BLINK—the researchers detected 33 SNP–trait associations across 11 chromosomes.

Eleven associations exceeded the Bonferroni-corrected threshold for genome-wide significance, and 22 were classified as suggestive. Several loci co-localized with genes involved in secondary cell-wall biosynthesis, transcriptional regulation, and cellular metabolism, making them candidates for further investigation. The analysis identifies statistical associations rather than demonstrating that individual markers directly cause the measured wood characteristics.

Nevertheless, the study establishes specific genomic targets that could support molecular breeding aimed at improving the mechanical, chemical, and energy-related value of dual-purpose rubberwood without overlooking latex productivity.

Subject of Research: Genetic associations with rubberwood mechanical, chemical, and energy-related traits

Article Title: Genome-wide association study reveals genetic loci controlling wood mechanical properties, lignocellulosic composition, and biomass energy traits in rubber tree (Hevea brasiliensis)

Article References: Phumichai, C., Rattanawong, R., Tonusin, T., Chotchutima, S., & Phumichai, T. (2026). Genome-wide association study reveals genetic loci controlling wood mechanical properties, lignocellulosic composition, and biomass energy traits in rubber tree (Hevea brasiliensis). BMC Plant Biology. https://doi.org/10.1186/s12870-026-09846-3

Image Credits: AI Generated

DOI: 10.1186/s12870-026-09846-3

Keywords: rubber tree, rubberwood, genome-wide association study, SNP markers, wood mechanics, lignocellulosic composition, biomass energy, heritability, genomic breeding, Hevea brasiliensis, Genome-wide, association