High-oleic acid content, nontransgenic allotetraploid cotton (Gossypium hirsutum L.) generated by knockout of GhFAD2 genes with CRISPR/Cas9 system.

Cotton (Gossypium hirsutum), the most important cash crop for natural textile fibers, meanwhile, represents the fifth largest source of vegetable oil for human consumption in the world. Typically, cottonseed oil contains three major fatty acids: 26% palmitic acid, 15% oleic acid, and 58% linoleic acid (Liu et al., 2002). The relatively high level of linoleic acid reduces oxidative stability of cottonseed oil, which can cause rancidity, a short shelf life and production of detrimental trans-fatty acids (Shockey et al., 2017). Oleic acid has better oxidative stability than linoleic acid due to its monounsaturated nature, so it is considered a reliable and healthy fatty acid.