Determination of the Effects of Exogenous Gibberellic Acid on Melon (Cucumis melo L.) Under Drought Stress

Abstract

This study aimed to investigate the effects of drought stress on melon (Cucumis melo L.) and to evaluate the potential mitigating role of gibberellic acid (GA₃) application. In the experiment, a 10-day drought period was imposed by withholding irrigation, and GA₃ was applied at a concentration of 100 ppm. The results indicated that drought stress significantly suppressed plant growth. The SPAD value decreased by 26%, from 303.6 ± 8.9 in the control group to 224.1 ± 5.9 under drought conditions, while GA₃ application did not lead to a statistically significant improvement. Drought stress increased malondialdehyde levels from 3.6 to 7.9, whereas GA₃ treatment reduced it to 5.67, indicating a partial alleviation of oxidative stress. Root length decreased from 50 ± 8.1 cm in the control to 31 ± 5.09 cm under drought stress and was further reduced to 25 ± 6.03 cm with GA₃ application. Principal Coordinate Analysis revealed that GA₃ application did not completely mitigate drought stress but provided partial improvement. These findings highlight the detrimental effects of drought stress on melon and indicate that GA₃ alone may not be sufficient to alleviate drought-induced damage in melon cultivation.

Keywords

• Melon
• abiotic stress
• plant growth regulator
• SPAD

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