Genome sequencing of four culinary herbs reveals terpenoid genes underlying chemodiversity in the Nepetoideae

<p>Species within the mint family, Lamiaceae, are widely used for their culinary, cultural, and medicinal properties due to production of a wide variety of specialized metabolites, especially terpenoids. To further our understanding of genome diversity in the Lamiaceae and to provide a resource for mining biochemical pathways, we generated high-quality genome assemblies of four economically important culinary herbs, namely, sweet basil (<i>Ocimum basilicum </i>L<i>.</i>), sweet marjoram (<i>Origanum majorana </i>L.), oregano (<i>Origanum vulgare </i>L<i>.</i>), and rosemary (<i>Rosmarinus officinalis </i>L<i>.</i>), and characterized their terpenoid diversity through metabolite profiling and genomic analyses. A total 25 monoterpenes and 11 sesquiterpenes were identified in leaf tissue from the four species. Genes encoding enzymes responsible for the biosynthesis of precursors for mono- and sesqui-terpene synthases were identified in all four species. Across all four species, a total of 235 terpene synthases were identified, ranging from 27 in <i>O. majorana</i> to 137 in the tetraploid <i>O. basilicum</i>. This study provides valuable resources for further investigation of the genetic basis of chemodiversity in these important culinary herbs.</p>