Abstract
We studied the effect of ethephon on levels of the major cannabinoids (tetrahydrocannabinol and cannabidiol) and chlorophyll, carotenoids and α-tocopherol in Cannabis sativa at productive stage. Results revealed that ethephon increased THC content of leaf in male and female plants and of male flowers. However, ethephon unable to enhancing THC content in female flowers. Treatment with etheohon increased CBD content in male and female leaf and female flowers. The treatment of male flowers with low ethephon concentration caused an increase, and those treated with high ethephon concentration resulted in a decrease in CBD content. The lowest level of ethephon (1 μM) enhanced chlorophyll a, b and total chlorophyll in male and female plants. Both sexes treated with ethephon showed an increase in carotenoids content, but 1 μM ethephon had the stronger effect in this regards. Male and female plants had a higher content of α-tocopherol when treated with ethephon. These results showed ethephon is a suitable treatment for increasing cannabinoids and α-tocopherol in productive stage of cannabis and there was not a relation between primary and secondary terpenoids.
