Bidens hawaiensis isolate:Cape Kumukahi | cultivar:wild Genome sequencing and assembly. Bidens hawaiensis isolate:Cape Kumukahi | cultivar:wild

The plant genus Bidens (Asteraceae; Coreopsidae) is a species-rich and circumglobal taxon. The 19 hexaploid species endemic to the Hawaiian Islands are considered an iconic example of adaptive radiation, of which many are imperiled and of high conservation concern. Until now, no genome resources were available for this genus, which may serve as a model system for understanding the evolutionary genomics of explosive plant diversification. Here, we present a high-quality genome reference for the Hawaiian endemic species B. hawaiensis reconstructed from long-read, high-fidelity sequences generated on a Pacific Biosciences Sequel II System. The haplotype-aware, draft genome assembly consisted of ~6.7 Giga bases, close to the holoploid genome size estimate of 7.56 Gb (plus/minus 0.44 SD) determined by flow cytometry. Collapsing the draft assembly into a consensus haploid representation resulted in a reference genome comprised of 15,958 contigs containing ~3.48 Giga bases, with a contig N50 value of 421,857. The high interspersed repeat content of the genome, approximately 74 percent, along with hexaploid status, contributed to assembly fragmentation. Both the haplotype-aware and consensus haploid assemblies recovered >95percent of Benchmarking Universal Single-copy Orthologs. Yet, the removal of alternate haplotigs did not substantially reduce the proportion of duplicated benchmarking genes (approximately 79 versus 68 percent). This reference genome will support future work on the speciation process during adaptive radiation, including resolving evolutionary relationships, determining the genomic basis of trait evolution, and supporting ongoing conservation efforts.