Ahmed soufi1*
1 Department of Field Crops, Faculty of Agriculture, Tishreen University, Lattakia, Syria.
(*Corresponding author: Ahmed. E-mail: 7mada.movo9@gmail.com, phone:+963991266905).
Received: 23/ 07/ 2024 Accepted: 8/ 10/ 2024
Abstract
The research was carried out in 2024, on the experimental farm in the village of Qara Falah in Latakia Governorate- Syria, to study the effect of treatment with melatonin acid at concentrations (50, 100 and 150 microliters) on some biochemical and productive characteristics of the local tobacco plant (Shak Al-Bint) under conditions of drought soil treatments by Poly Ethylene Glycol (PEG) solutions (15, 30 and 45 %), corresponding to final osmotic potentials -0.52, -1.04 and -1.56 MPa, which were distributed according to the randomized complete design (R.C.D) with three replicates. Many important indicators were measured, including: leaf content of: chlorophyll (µg/g), proline (µmol/g), manol d-aldehyde MDA (nmol/g), and yield of green and dry leaves (g/plant). The results showed a decrease in the green tobacco yield (75 g/plant) and dry (20 g/plant) under drought stress conditions at a concentration of 45%. The chlorophyll content of the leaves also decreased steadily with increasing applied stress, which in this context reached (463 μg/g). In contrast, the chlorophyll content of the leaves increased when spraying with melatonin at a concentration of 50 μl (710 μg/g), which was positively reflected on the green and dry leaf yield. The proline content of the leaves also decreased (0.9 μmol/g), especially at a low concentration of melatonin. The results showed that the treatment with a diluted concentration of melatonin acid was superior to all treatments and the control for all studied indicators. Therefore, it is recommended to use melatonin acid, especially at a low concentration (50) μl, for its role in improving many chemical indicators, which is reflected in increasing tobacco productivity under drought stress conditions.
Keywords: melatonin, tobacco, Shak Al-Bint cultivar, drought stress.
Full paper in Arabic: PDF