The interactive effects of salinity and drought stress on germination, seedling growth, and physiological parameters of pumpkin

Year 2025, Volume: 9 Issue: 2, 309 - 318, 26.06.2025

Gamze Kaya

https://doi.org/10.31015/2025.2.5

Abstract

This study aimed to explore the response of pumpkin to salt and drought stress during germination and early plant growth stages. Salt stress was induced with various sodium chloride concentrations (0.00%, 0.25%, 0.50%, and 0.75%) in non-drought (distilled water) and drought (15% PEG-6000) conditions. The seeds of the pumpkin cultivar T28 for snacks were germinated between filter papers using the respective solutions. In the pot experiment, the seedlings at the 2-leaf stage were exposed to these stresses for 30 days. The plant height, fresh weight, dry weight, leaf area, leaf dry matter, chlorophyll content (Chl), relative water content (RWC), and cell membrane stability (CMS) of the plants were inquired. Drought markedly reduced the germination index, plant height, fresh weight, dry weight, leaf area, RWC, and CMS. Conversely, increased mean germination time, Chl, and dry matter were determined in drought conditions. Salinity stress above 0.50% NaCl influenced these traits, with salinity’s inhibitory effects surpassing those of drought. Germination percentage dropped from 100% to 46% at 0.75% NaCl under drought, whereas it remained stable under non-drought stress. Pumpkin was more sensitive to drought and salinity stress at the germination stage than at the early growth stage. The correlation between germination and seedling growth parameters indicated that the germination index and mean germination time were substantially associated with nearly all growth traits of pumpkin. The study highlights the germination index as a key indicator of stress tolerance and identifies 0.50% NaCl as a critical threshold level for pumpkin under salt and drought stress.

Keywords

Cucurbita pepo L., Drought, Salinity, Germination, Plant growth, Cell membrane stability

Ethical Statement

Peer-review Externally peer-reviewed. Declaration of Interests The author declare no conflict of interest. The paper is original unpublished work, and it is not under consideration for publication anywhere else. Author Contribution Conceptualization, methodology, and final version were done independently by Gamze Kaya

Thanks

The author would like to thank Dr. E.G. Kulan and MSc. E. Yaman for their assistance, and the Department of Field Crops, Eskişehir Osmangazi University for providing the facilities of the Seed Science and Technology Laboratory.

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