Wild coriander: an untapped genetic resource for future coriander breeding

Coriander, Coriandrum sativum L., is globally cultivated for various purposes, including cooking, cosmetics and traditional medicine. Coriander has been cultivated for thousands of years and desiccated coriander fruits were found in various Mediterranean archaeological sites. The existence of wild coriander that is not a cultivation escapee is questioned. This work aimed to determine whether coriander growing wild in Israel significantly differs from cultivated genotypes and might be used for future breeding purposes. Nine coriander accessions originating from wild populations were evaluated for their fruit morphology, germination rates, growth rates, and fruit volatile content in comparison to those of nine cultivated genotypes. Wild accession fruits were found to have a harder and thicker coat and a low germination rate, that was recovered by seed rescue, suggesting stronger mechanical dormancy as compared to the cultivated varieties. Wild coriander fruits had a significantly lower essential oil content but a similar volatile profile in comparison to cultivated coriander. When grown under the same irrigation conditions, wild accessions had a much smaller vegetative appearance than cultivated coriander. This study documented the existence of wild coriander accessions that are markedly different from the cultivated genotypes. We illustrate two theories for their origin: 1) they are a separate subset or outliers in the C. sativum species that may have escaped domestication. 2) they represent the ancestor of the modern coriander crop. Future genomic studies will assist in judging which hypothesis holds.