Abstract:
Woody perennial angiosperms (i.e., hardwood trees) are polyphyletic in origin and occur
in most angiosperm orders. Despite their independent origins, hardwoods have shared
physiological, anatomical, and life history traits distinct from their herbaceous relatives.
New high-throughput DNA sequencing platforms have provided access to numerous
woody plant genomes beyond the early reference genomes of Populus and Eucalyptus,
references that now include willow and oak, with pecan and chestnut soon to follow.
Genomic studies within these diverse and undomesticated species have successfully
linked genes to ecological, physiological, and developmental traits directly. Moreover,
comparative genomic approaches are providing insights into speciation events while
large-scale DNA resequencing of native collections is identifying population-level genetic
diversity responsible for variation in key woody plant biology across and within
species. Current research is focused on developing genomic prediction models for
breeding, defining speciation and local adaptation, detecting and characterizing somatic
mutations, revealing the mechanisms of gender determination and flowering, and
application of systems biology approaches to model complex regulatory networks
underlying quantitative traits. Emerging technologies such as single-molecule, long-read
sequencing is being employed as additional woody plant species, and genotypes
within species, are sequenced, thus enabling a comparative (“evo-devo”) approach to
understanding the unique biology of large woody plants. Resource availability, current
genomic and genetic applications, new discoveries and predicted future developments
are illustrated and discussed for poplar, eucalyptus, willow, oak, chestnut, and pecan.
