Mohammad Amin Ghezel - Department of Horticultural Sciences, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran
Azim Ghasemnezhad - Department of Horticultural Sciences, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran
Khodayar Hemmati - Department of Horticultural Sciences, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran
Omid Sohrabi - Department of Horticultural Sciences, Guilan University, Rasht, Iran

The indeterminate behavior of evening primrose is a frequent limitation in its cultivation. Controlling the final growth of plants at a certain stage is important. In the present ‎experiment, different plant extracts were compared functionally with ‎cycocel at different times of application. The experiment was performed as a factorial experiment based on a ‎randomized complete block design with three replications. Treatments included normal water ‎‎(control), cycocel (zero and ۱۰۰ ppm), walnut (Juglans regia L.) leaf extract (zero and ۲۵%), oak ‎fruit extract (Quercus castaneifolia L.) (zero and ۲۵%), and cotton ‎capsule extract (Gossypium hirsutum L.) (zero and ۲۵%). Evaluations were made on the seeds, oil yield and yield-components. The foliar application significantly reduced stem length (۴۳-۸۰%) and plant height (۱۳-‎‎۳۳%), but increased the percentage of oils (۱۸.۷۵%) and free fatty acids (۶۷.۵%). The highest ‎oil content (۳۵%) occurred in response to a combination of walnut, oak, cotton extracts, and cycocel.‎ The highest amount of free fatty acids (۲۳%) indicated more immature seeds and ‎was obtained under the treatment of cotton extract. Natural extracts increased the oil percentage, but reduced ‎the free fatty acid percentage and the stem length. It seems that further studies in this ‎regard can help control non-terminal growth of evening primrose without having a need for breeding ‎programs.

Free fatty acids, medicinal plants, oil percentage, plant for plant, Plant extract