Woody oil crop domestication in the genus Camellia: Perspectives on future breeding

Oilseed <i>Camellia</i>, including diverse species within the <i>Camellia</i> genus, valued for high seed-oil content, is the dominant woody oil crop in China. We reviewed the key issues in oilseed <i>Camellia</i> domestication and its origin. Major oilseed <i>Camellia</i> species are polyploids within <i>Camellia</i> sect. <i>Paracamellia</i>, with the highest species diversity in the Nanling Mountains areas. Oilseed <i>Camellia</i> began to be cultivated as oil crops 400 years ago in the subtropical hilly areas of the Yangtze River Basin. Domestication may have led to significantly larger fruits and higher oleic acid content, but the genetic mechanisms remain unknown. Interspecific hybridization and polyploidization may have contributed to the origin of major oilseed <i>Camellia</i>, generating rich diversity in fruit traits. Perspectives are proposed on future breeding, including resolving molecular mechanisms of key traits, improving abiotic tolerance, and creating new germplasms via hybridizations. This review may guide the efficient exploration and utilization of genetic resources for improving oilseed <i>Camellia</i>.