1. The thesis aims to investigated the effects of melatonin and boron on tomato growth, yield, physiological and biochemical traits under salt stress.

The study included evaluating the effect of treatments on a number of vegetative and productive traits, including plant height, leaf area, dry weight, and yield, in addition to estimating chlorophyll and proline content, catalase and peroxidase enzyme activity, and fruit content of lycopene, vitamin C, and reducing sugars, as well as estimating leaf content of nitrogen, phosphorus, and potassium, and analyzing the effect of the interaction between melatonin and boron under different levels of salinity, which included three levels of salinity (0, 2000, 4000 mg L⁻¹ of sodium chloride), three levels of melatonin (0, 200, 400 mg L⁻¹), and three levels of boron (0, 5, 10 mg L⁻¹).

1. The potential use of melatonin at a concentration of 400 mg/L with boron at a concentration of 5 mg/L to improve tomato growth and yield under saline stress conditions.
2. Conducting future studies to test other concentrations of melatonin and boron on different tomato varieties and horticultural crops.
3. Studying the physiological and molecular effects of melatonin and boron, and expanding their use within integrated management programs to mitigate salinity damage.

• The researcher was awarded the rating “Excellent.”