聚乙二醇和脯氨酸通过芒果生理生化重编程协同提高耐盐性。

Polyethylene glycol and proline synergistically improve salinity tolerance via physiological and biochemical reprogramming in mango.

作者信息

Kheshin Mohamed El, Hmmam Ibrahim

机构信息

Pomology Department, Faculty of Agriculture, Cairo University, PO box 12613, Giza, Egypt.

出版信息

BMC Plant Biol. 2025 Aug 29;25(1):1161. doi: 10.1186/s12870-025-07211-4.

DOI:10.1186/s12870-025-07211-4

PMID:40883675

Abstract

BACKGROUND

Mango (Mangifera indica L.) is a globally important fruit crop, but its sensitivity to salt stress poses a serious threat to its sustainable cultivation. Salt stress impairs mango growth through osmotic imbalance, ion toxicity, oxidative damage, and reduced nutrient uptake. This study examined the biochemical, physiological, vegetative, and reproductive responses of the Egyptian mango cultivar 'Ewais' under constant salinity stress reflecting the naturally saline irrigation water in the orchard. The research specifically aimed to evaluate the efficacy of polyethylene glycol (PEG) and proline in mitigating the adverse effects of salt exposure. Nine treatments were tested over two consecutive growing seasons (2023 and 2024). The treatments consisted of PEG applied individually at 15 mM (T) and 30 mM (T), as well as proline applied at 8 mM (T) and 13 mM (T). Four combinations were also examined, including T + T (T), T + T (T), T + T (T), and T + T (T). A control group (T) consisted of trees subjected to the same salinity conditions without any application of PEG or proline.

RESULTS

The treatments investigated revealed significant improvements in relative water content (RWC), membrane stability index (MSI), peroxidase (POD) and polyphenol oxidase (PPO) activities, chlorophyll concentration, ascorbate accumulation, proline concentration, total soluble sugar metabolism, and the hormonal balance of indole-3-acetic acid (IAA) and abscisic acid (ABA). Also, positive responses were observed in vegetative growth traits such as shoot elongation, number of flushes, and leaf area, as well as in reproductive traits including fruit set percentage, average fruit weight, and yield. Specifically, the combined treatments of PEG and proline, T (PEG 30 mM + Proline 13 mM) and T (PEG 30 mM + Proline 8 mM), led to sustained improvements in physiological and agronomic performance.

CONCLUSION

The findings support a dual-action mechanism in which PEG triggers osmotic signalling, while proline contributes to maintaining antioxidant defences and metabolic stability, thereby establishing PEG-proline co-application as a promising strategy for enhancing mango productivity under saline conditions.

摘要

背景

芒果（Mangifera indica L.）是一种全球重要的水果作物，但其对盐胁迫的敏感性对其可持续种植构成严重威胁。盐胁迫通过渗透失衡、离子毒性、氧化损伤和养分吸收减少来损害芒果生长。本研究考察了埃及芒果品种‘埃威斯’在反映果园自然咸水灌溉水的恒定盐胁迫下的生化、生理、营养和生殖反应。该研究具体旨在评估聚乙二醇（PEG）和脯氨酸在减轻盐暴露不利影响方面的功效。在连续两个生长季节（2023年和2024年）对九种处理进行了测试。处理包括分别以15 mM（T1）和30 mM（T2）施用的PEG，以及以8 mM（T3）和13 mM（T4）施用的脯氨酸。还考察了四种组合，包括T1+T3（T5）、T1+T4（T6）、T2+T3（T7）和T2+T4（T8）。一个对照组（T9）由在相同盐度条件下未施用任何PEG或脯氨酸的树木组成。

结果

所研究的处理在相对含水量（RWC）、膜稳定性指数（MSI）、过氧化物酶（POD）和多酚氧化酶（PPO）活性、叶绿素浓度、抗坏血酸积累、脯氨酸浓度、总可溶性糖代谢以及吲哚-3-乙酸（IAA）和脱落酸（ABA）的激素平衡方面显示出显著改善。此外，在诸如新梢伸长、抽梢次数和叶面积等营养生长性状以及包括坐果率、平均果实重量和产量等生殖性状方面也观察到了积极反应。具体而言，PEG和脯氨酸的组合处理，即T7（PEG 30 mM+脯氨酸13 mM）和T8（PEG 30 mM+脯氨酸8 mM），导致生理和农艺性能持续改善。