Welcome to Chinese Journal of Applied Ecology! Today is Share:

Chinese Journal of Applied Ecology ›› 2025, Vol. 36 ›› Issue (4): 1099-1108.doi: 10.13287/j.1001-9332.202504.019

• Original Articles • Previous Articles     Next Articles

Aluminum absorption capacity of different cultivars of Hydrangea macrophylla seedlings under aluminum stress and the physiological and biochemical mechanisms

CHEN Wenjuan1,2, CHEN Shuangshuang2, FENG Jing2, CHEN Huijie2, ZHOU Huimin2, LIU Xintong2, ZHANG Xuhui1*, DENG Yanming1,2   

  1. 1Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China;
    2Institute of Leisure Agriculture, Jiangsu Academy of Agricultural Sciences/Provincial Key Laboratory for Horticultural Crops Genetics and Improvement, Nanjing 210014, China
  • Received:2024-10-16 Accepted:2025-03-02 Online:2025-04-18 Published:2025-10-18

Abstract: Hydrangea macrophylla exhibits strong tolerance to acid and aluminum stress. Many cultivars can absorb Al3+ from soils, resulting in variations of their flower color from red to blue. This characteristic presents a potential avenue for the ecological remediation of aluminum-rich acidic soils. To assess the capacities of aluminum absorption among different cultivars, we utilized the cutting seedlings of 45 popular H. macrophylla cultivars via hydroponic culture, which were treated under 0 (control) and 800 μmol·L-1 Al2(SO4)3. The aluminum absorption abilities were determined through root tip staining and aluminum content determination methods. We selected two representative cultivars with the strongest or weakest aluminum absorption capacities for further investigation of the physiological and biochemical mechanisms under aluminum stress. The results showed that the 45 cultivars could be categorized into five levels according to their aluminum absorption capacities: strong, relatively strong, intermediate, relatively weak, and weak, comprising 2, 11, 15, 15, and 2 cultivars, respectively. Amongst them, Bailer and White angel were identified as representative of strong and weak aluminum absorption capacities, respectively. In comparison to White angel, the aluminum-treated Bailer exhibited significant increases in chlorophyll content, transpiration rate, net photosynthetic rate, intercellular CO2 concentration, and stomatal conductance with significant increase of 24.8%, 63.9%, 11.2%, 9.2%, and 66.7%, root length, root surface area, root volume, and root tip number increased by 4.7%, 2.9%, 14.3%, and 7.8%, the activities of antioxidant enzymes (peroxidase, catalase, and superoxide dismutase), and the contents of soluble sugar and soluble proteins exhibited significant increases by 88.4%, 35.3%, 7.7%, 2.4%, and 21.7% in the roots, and 78.4%, 103.7%, 101.1%, 138.9%, and 18.1% in the leaves, respectively. These findings suggested that Bailer could effectively mitigate damage from Al stress by enhancing photosynthesis, antioxidant enzymatic activities, and nonenzymatic antioxidants, thereby improving its aluminum absorption ability and tolerance, which has the potential application in the remediation of aluminum-rich acidic soils.

Key words: Hydrangea macrophylla, aluminum absorption, acidic soil, physiological and biochemical mechanism