Amgad Farah(1)* , Rama Aziz(1) and OsamaAL Abdullah(2)
(1). Hort. Dep., Fac. Agri., Damascus Univ., Damascus, Syria.
(2). Horticultural Research Department, General Commission for Scientific Agricultural Research, Damascus, Syria.
(*Corresponding author: Amgad Farah, E.mail Stevanamgad@gmail.com).
Received: 26/01 / 2023 Accepted: 14 /03/ 2023
Abstract:
The experiment was carried out in the centers of the General Comssion for Scientific Agricultural Research during two growing seasons (2022-2023), in order to study the effect of foliar spraying with licorice extract (GL1, GL2, GL3) 5, 10, 15 g/L, and gibberellin acid (GA1, GA2, GA3) 5, 10, 15 mg/L in addition to the control without spraying. lettuce spraying was done at the stage of formation of the true leaves of the plant (4-5), and at a rate of one spray every two weeks until the stage of completion of vegetative growth, the foliar spraying treatments contributed with licorice extract and acid Al-Gabrielin in improving the characteristics of vegetative growth and the specific and productive characteristics of lettuce, The design of the experiment was factorial, according to complete randomization, with three replications for one treatment.The results show that the treatment of foliar spraying with gibberellin acid GA3 at a concentration of 15 mg/L was significantly superior to all other treatments in field indicators, such as average plant height (33.13) cm, head circumference (54.28) cm, head weight (677.8) g,, and productivity (3000) kg/m2, and it also excelled significantly in qualitative traits such as the average percentage of humidy (93.49)%, the content of carotenoids (12.38) mg/L, and the content of chlorophyll A and B (0.530, 0.180) mg/L. L, followed by a significant superiority of the treatment of spraying with licorice extract GL3 over all other treatments and in all studied traits.While the control treatment, GG, gave the lowest value in all traits, and the site of Al-Taybeh in the countryside of Damascus was superior to the site of Khan Arnabeh in all studied field and laboratory indicators. The results confirm the importance of spraying plant extracts and using them as natural alternatives because they are free of chemicals and their harmful effect on human health and the environment, because the treatment of foliar spraying with licorice extract gave close results with gibberellin acid in the vegetative, quality and productivity indicators of lettuce.
Key words: Gibberellin acid, licorice extract, lettuce, foliar spray.
Full paper in Arabic: pdf