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

Year 2025, Volume: 12 Issue: 2, 155 - 161, 30.06.2025

Seher Toprak , Ömer Faruk Coşkun

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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