Cao Yangfan, Yan Ruiyang, Sun Mingcong, Guo Jing, Zhang Shuyong
State Forestry and Grassland Administration Key Laboratory of Silviculture in Downstream Areas of the Yellow River, College of Forestry, Shandong Agricultural University, Tai'an, 271018, China.
BMC Plant Biol. 2025 Apr 3;25(1):419. doi: 10.1186/s12870-025-06424-x.
Soil salinity is a major barrier to plant growth and yield improvement. Chitosan, a versatile biomaterial, has shown potential in enhancing plant stress tolerance. This study evaluated the effectiveness of chitosan pretreatment in mitigating salt stress hibiscus (Hibiscus syriacus L.). Two-year-old hibiscus cuttings were treated with varying concentrations of chitosan (10 mg/L, 25 mg/L, 50 mg/L, 100 mg/L) via root irrigation and foliar spray in a 6‰ saline environment. Growth parameters, gas exchange rates, antioxidant enzyme activities, and osmotic regulatory compounds were analyzed.
The results showed that chitosan at 25 mg/L and 50 mg/L significantly improved physiological and ecological traits. These concentrations enhanced photosynthetic performance, protected photosynthetic electron transport chain, and reduced malondialdehyde (MDA) content and relative conductivity, thereby limiting cell membrane damage. Additionally, the accumulation of soluble proteins, soluble sugars, and proline increased, improving the plants' ability to cope with salt stress. Antioxidant enzyme activities, including superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX), were notably elevated, while levels of hydrogen peroxide (H₂O₂) and superoxide anion (O₂ decreased.
The 25 mg/L and 50 mg/L treatments had the most pronounced effects, confirming that moderate chitosan concentrations effectively alleviate salt stress in hibiscus. This study underscores the role of chitosan in enhancing salt stress adaptability, offering insights for plant protection and greening efforts.
土壤盐渍化是植物生长和产量提高的主要障碍。壳聚糖作为一种多功能生物材料，已显示出增强植物抗逆性的潜力。本研究评估了壳聚糖预处理对减轻木槿（Hibiscus syriacus L.）盐胁迫的有效性。在6‰的盐环境中，通过根部灌溉和叶面喷施，用不同浓度的壳聚糖（10mg/L、25mg/L、50mg/L、100mg/L）处理两年生木槿插条。分析了生长参数、气体交换率、抗氧化酶活性和渗透调节化合物。
结果表明，25mg/L和50mg/L的壳聚糖显著改善了生理和生态性状。这些浓度提高了光合性能，保护了光合电子传递链，降低了丙二醛（MDA）含量和相对电导率，从而限制了细胞膜损伤。此外，可溶性蛋白、可溶性糖和脯氨酸的积累增加，提高了植物应对盐胁迫的能力。超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）和抗坏血酸过氧化物酶（APX）等抗氧化酶活性显著升高，而过氧化氢（H₂O₂）和超氧阴离子（O₂）水平降低。
25mg/L和50mg/L的处理效果最为显著，证实了适度的壳聚糖浓度能有效缓解木槿的盐胁迫。本研究强调了壳聚糖在增强盐胁迫适应性方面的作用，为植物保护和绿化工作提供了见解。
