Distributions and conservation status of carrot (Daucus L.) wild relatives in Tunisia: A case study in the Western Mediterranean basin

Authors: MEZGHANI, NAJLA - National Bank Of Genes; Khoury, Colin; Carver Jr, Daniel; ACHICANOY, HAROLD - International Center For Tropical Agriculture (CIAT); Simon, Philipp; Spooner, David

Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/16/2019
Publication Date: 8/27/2019
Citation: Mezghani, N., Khoury, C.K., Carver Jr, D.P., Achicanoy, H.A., Simon, P.W., Spooner, D.M. 2019. Distributions and conservation status of carrot (Daucus L.) wild relatives in Tunisia: A case study in the Western Mediterranean basin. Crop Science. 59:1-12. https://doi.org/10.2135/cropsci2019.05.0333.
DOI: https://doi.org/10.2135/cropsci2019.05.0333

Interpretive Summary: Crop wild relatives, the wild cousins of cultivated plants, are valuable for crop improvement. But gaps in knowledge about their taxonomic designations, where they occur, and what traits they might be useful for, currently limit their use in plant breeding and weaken their conservation. We compile the state of knowledge on the taxonomy and distributions of the wild relatives of carrot natively occurring within Tunisia - a hotspot of wild carrot diversity. We assess their conservation status and investigate their potential adaptations to climatic stress. We categorize three of the species high priority for further conservation, five medium priority, and five low priority, with none currently considered sufficiently conserved. Geographic hotspots, especially in the northern coastal areas, represent particularly high value regions for further collecting for genebank conservation and for protection in their natural habitats. USDA is an equal opportunity employer and provider.

Technical Abstract: Crop wild relatives, the wild progenitors and closely related cousins of cultivated plant species, are sources of valuable genetic resources for crop improvement. Persisting gaps in knowledge of taxonomy, crossability, distributions, and characterization for traits of interest constrain their expanded use in plant breeding, and likewise negatively affect ex situ (in genebanks) and in situ (in natural habitats) conservation planning. We compile the state of knowledge on the taxonomy and distributions of the wild relatives of carrot (genus Daucus L.) natively occurring within Tunisia - a hotspot of diversity of the genus, containing 13 taxa (27% of species worldwide). We assess their ex situ and in situ conservation status and use ecogeographic information to characterize their potential adaptations to abiotic stresses of interest in crop breeding. We categorize three of the taxa high priority for further conservation both ex situ and in situ, five medium priority, and five low priority, with none currently considered sufficiently conserved. Geographic hotspots for species diversity, especially in the northern coastal areas, represent particularly high value regions for efficient further collecting for ex situ conservation and for in situ protection. We find substantial ecogeographic variation both across taxa and between populations within taxa, with regard to adaptation to high temperatures, low precipitation, and other traits of potential interest. USDA is an equal opportunity employer and provider.