Yang Xiao, Tan Ai-Juan, Zheng Meng-Meng, Feng Dan, Mao Kang, Yang Gui-Li
Key laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), Collaborative Innovation Center for Mountain Ecology & Agro-Bioengineering (CICMEAB), College of Life Sciences/Institute of Agro-bioengineering, Guizhou University, Guiyang 550025, Guizhou Province, China.
Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, Guizhou Province, China.
Sci Total Environ. 2023 Dec 1;902:166056. doi: 10.1016/j.scitotenv.2023.166056. Epub 2023 Aug 7.
Duckweed is a cadmium (Cd) hyperaccumulator. However, its enrichment characteristics and physiological responses to Cd have not been systematically studied. The physiological responses, enrichment characteristics, diversity of endophytic bacterial communities, and isolation of Cd-resistant endophytes in duckweed (Lemna minor 0014) were studied for different durations and Cd concentrations. The results indicated that peroxidase (POD) and catalase (CAT) activities decreased while superoxide dismutase activity first increased and then decreased with increasing Cd stress duration. POD activities, CAT activities, and O increased as Cd concentrations increased. Malondialdehyde content and Cd accumulation in duckweed increased with increasing concentrations and time. This endophytic diversity study identified 488 operational taxonomic units, with the dominant groups being Proteobacteria, Firmicutes, and Actinobacteria. Paenibacillus sp. Y11, a strain tolerant to high concentrations of Cd and capable of significantly promoting duckweed growth, was isolated from the plant. Our study revealed the effects of heavy metals on aquatic plants, providing a theoretical basis for the application of duckweed in water pollution.
浮萍是一种镉（Cd）超富集植物。然而，其对镉的富集特性和生理响应尚未得到系统研究。本研究针对不同时长和镉浓度，对浮萍（小浮萍0014）的生理响应、富集特性、内生细菌群落多样性以及耐镉内生菌的分离进行了研究。结果表明，随着镉胁迫时间的增加，过氧化物酶（POD）和过氧化氢酶（CAT）活性降低，而超氧化物歧化酶活性先升高后降低。随着镉浓度的增加，POD活性、CAT活性和O增加。浮萍中丙二醛含量和镉积累量随浓度和时间的增加而增加。这项内生菌多样性研究共鉴定出488个可操作分类单元，优势菌群为变形菌门、厚壁菌门和放线菌门。从该植物中分离出了一株对高浓度镉具有耐受性且能显著促进浮萍生长的芽孢杆菌属菌株Y11。我们的研究揭示了重金属对水生植物的影响，为浮萍在水污染治理中的应用提供了理论依据。
