This study happened in 2021–2023 at the Plant Tissue Culture Laboratory, College of Agriculture, University of Basrah, Basrah, Iraq. The presented study determined the effect of adding sucrose, salicylic acid, and polyethylene glycol (PEG) to shoot multiplication of the Grand Nain banana plant. The results revealed the concentration of sucrose (90 g L^-1) was significantly superior by recording the highest number of shoots, plant height, the number of leaves, and the leaf width with values of 18.33 shoots, 7.10 cm, 6.33 leaves, and 3.83 cm, respectively. In contrast, the utmost concentration of melatonin emerged with the sucrose treatment 120 g. L^-1. The treatment of salicylic acid (2.0 mg L^-1) provided the best results for studied qualities. The salicylic acid concentration of 3.0 mg L^-1 resulted in the maximum concentration of melatonin (41.56 mg g^-1 dry weight). The PEG concentration of 1.0 g L^-1 was significantly superior by recording the highest values, while the PEG concentration at 3.0 g L^-1 gave the topmost value of melatonin (43.32 mg g^-1 dry weight).

Keywords: Maize (Zea mays L.), water stress, silicon, yield, carbohydrate, protein, oil, stresstolerance index

Key findings: Banana Grand Nain (Musa acuminata L.), isolation melatonin, micropropagation