The FAO/IPGRI Multi-Crop Passport Descriptor is part of the Crop Ontology (CO) project. The ontology has been adapted from the December 2015 version of the FAO/Bioversity Multi-Crop Passport Descriptors. Reference Plant Ontologies are being developed in the context of the Planteome project and are being integrated with the Crop Ontology, which provides harmonized breeders’ trait names, measurement methods, scales and standard variables for many crops. This ontology is one of these reference plant ontologies integrated within the Crop Ontology.