Rafique Maham, Noreen Zahra, Usman Sheeraz, Shah Anis Ali, Taj Hafsa, El-Sheikh Mohamed A, Lee In Jung
Department of Botany, Division of Science and Technology, University of Education, Lahore, Pakistan.
Botany and Microbiology Department, College of Science, King Saud University, Riyadh, Saudi Arabia.
Sci Rep. 2025 Mar 17;15(1):9062. doi: 10.1038/s41598-025-93672-4.
Cadmium (Cd) stress is considered among the most harmful abiotic stresses because of its toxicity and ability to alter the ultrastructure of plants. Lettuce (Lactuca sativa L.) can readily accumulate Cd from the soil, but its elevated level posed negative effect on their development and nutritional quality. In this study, efficacy of chitosan and spermidine synergistic application was evaluated to improve Cd metal tolerance or its exclusion in lettuce. A pot experiment was conducted in a four-way completely randomized design (CRD) with 3 replicates, using two L. sativa varieties (VRIL-0205 and Green Check). Following treatments, Cd stress (10 ppm CdCl), chitosan (200 ppm) and spermidine (145 ppm) were applied along with their respective controls. The negative effects of Cd stress on the morphological, physiological, and biochemical attributes of both L. sativa varieties were evaluated along with counter effect of chitosan and spermidine alone and synergistic application. Cd stress resulted in significant accumulation of Cd ions in the shoot of both varieties (0.038 mg kg in VRIL-0205 and 0.041 mg kg in Green Check). It also impaired growth, biomass, gas exchange, water relation, antioxidant activities and nutrient uptake in both varieties. Foliar application of both chitosan and spermidine improved growth, biomass, chlorophyll content, photosynthesis rate, stomatal conductance, water content, antioxidant activities and nutrient uptake in both control and stressed plants. Their combined treatment reduced stress indicators including relative membrane permeability (VRIL-0205; 19% and Green Check; 22%), HO (VRIL-0205; 27% and Green Check; 26%) and malondialdehyde content (VRIL-0205; 6% and Green Check; 7%) in stressed plants, compared with stress only plants. These findings showed that chitosan and spermidine synergistic application effectively mitigated the Cd toxicity in both L. sativa varieties and improved their growth under stress condition. This study provides insight into the potential use of chitosan and spermidine foliar spray as sustainable tools for improving Cd resilience in crop plants.
镉（Cd）胁迫因其毒性以及改变植物超微结构的能力，被认为是最有害的非生物胁迫之一。生菜（Lactuca sativa L.）能够轻易地从土壤中积累镉，但其含量升高会对生菜的生长发育和营养品质产生负面影响。在本研究中，评估了壳聚糖和亚精胺协同施用对提高生菜对镉的耐受性或减少镉吸收的效果。采用四因素完全随机设计（CRD）进行盆栽试验，设置3次重复，使用两个生菜品种（VRIL - 0205和Green Check）。试验设置了以下处理：镉胁迫（10 ppm CdCl）、壳聚糖（200 ppm）和亚精胺（145 ppm）及其各自的对照。评估了镉胁迫对两个生菜品种形态、生理和生化特性的负面影响，以及壳聚糖和亚精胺单独施用和协同施用的对抗作用。镉胁迫导致两个品种地上部显著积累镉离子（VRIL - 0205中为0.038 mg/kg，Green Check中为0.041 mg/kg）。它还损害了两个品种的生长、生物量、气体交换、水分关系、抗氧化活性和养分吸收。叶面喷施壳聚糖和亚精胺均提高了对照植株和受胁迫植株的生长、生物量、叶绿素含量、光合速率、气孔导度、含水量、抗氧化活性和养分吸收。与仅受胁迫的植株相比，它们的联合处理降低了胁迫指标，包括受胁迫植株的相对膜透性（VRIL - 0205为19%，Green Check为22%）、过氧化氢（VRIL - 0205为27%，Green Check为26%）和丙二醛含量（VRIL - 0205为6%，Green Check为7%）。这些结果表明，壳聚糖和亚精胺协同施用有效地减轻了两个生菜品种的镉毒性，并改善了它们在胁迫条件下的生长状况。本研究为叶面喷施壳聚糖和亚精胺作为提高作物对镉耐受性的可持续工具的潜在应用提供了见解。
