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Wang, et al.

the excessive use of acidic fertilizers and unsustainable essential elements for the synthesis of phospholipids,
agricultural practices. 6 nucleic acids, adenosine triphosphate, and other
Globally, about 30% of arable land and nearly half of biological macromolecules and is involved in various
potentially cultivable land are experiencing significant metabolic activities of plants. In acidic soils,
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soil acidification, as evidenced by decreasing soil pH P deficiency and Al toxicity often occur simultaneously,
levels, which leads to an excess of soluble Al ions in the which restricts the growth of plants. However, in acidic
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soil. Plants alleviate Al toxicity by releasing organic soils, P readily couples with excess Al ions produced by
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acids (such as malate and citrate) into the rhizosphere, leaching, and thus, the available P content in the soil
where these acids form stable, non-toxic complexes with that can be used by plants is extremely low, which has a
Al ions, thereby reducing their phytotoxic effects. Due great impact on the growth and metabolism of plants.
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to their prolonged exposure to soil environments, plant The combined stress of high Al and low P contents in
root tissues generally demonstrate the highest sensitivity soil has become a key factor restricting the productivity
to Al stress among all plant parts. The inhibitory effect of woody plants. Specifically, due to the coupling
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of Al on root growth in soybean plants (Glycine max mechanism of P and Al, P has become an important
[L.] Merr.) becomes evident within merely five minutes target to alleviate Al stress. Sun et al. showed that under
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of exposure at a remarkably low Al concentration of relatively high Al stress, P increased the Al resistance of
75 μmol/L. Kochian et al. reported that Al ions can Lespedeza bicolor, an Al-tolerant species, and promoted
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combine with pectin and other components in the root the growth of its aboveground parts. Liu et al. studied
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cell wall, disrupting its structure, impairing its function, Chinese fir seedlings and reported that the height and
and subsequently inhibiting the growth of aboveground length of the roots of Chinese fir seedlings increased in
parts. Recent studies demonstrate that an Agrobacterium response to the addition of exogenous P, indicating that
tumefaciens-loaded microneedle delivery system P alleviated the growth of Chinese fir seedlings under
successfully transfers the green fluorescent protein Al stress.
gene into both apical meristems and leaves of Camellia oleifera Abel, a member of the
tobacco (Nicotiana tabacum) plants, achieving stable Camelliaceae family, is extensively cultivated in the
transgene expression and enhanced stress resistance. acidic red soil regions in southern China, and is
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This approach provides a novel platform for the renowned for producing one of the world’s four major
efficient delivery of stress-resistance genes in plant woody edible oils. Al plays a pivotal role in the soil
biotechnology. Yu et al. demonstrated that Al stress environment, influencing the growth of C. oleifera.
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significantly inhibits rapeseed growth, particularly Excessive soil leaching results in acidic soils that
through the reduction of root length and biomass. are rich in Al but deficient in P, which significantly
Notably, cerium oxide nanoparticles can improve the hampers the development and yield of C. oleifera.
growth performance of rapeseed and cotton seedlings The expansion of acid rain-affected areas in southern
under salt stress by scavenging and eliminating excess China, coupled with the misuse of acidic fertilizers
reactive oxygen species (ROS), thereby enhancing and inappropriate tillage practices, has exacerbated
their salt tolerance. Similarly, in hybrid Liriodendron the conversion of insoluble Al into its toxic forms,
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chinense, Al stress not only restricts growth but also such as Al³⁺, Al(OH)²⁺, and Al(OH) . Furthermore, the
2+
disrupts cellular redox homeostasis, leading to the prevalent issue of extensive management in C. oleifera
accumulation of ROS. Notably, the application of forests makes the plants particularly susceptible to the
xiaminobutyric acid (GABA) has been shown to detrimental effects of excessive Al ion toxicity. Recent
mitigate these adverse effects by enhancing plant advancements in metabolomics have opened new
growth parameters, such as biomass and root length. avenues for investigating the mechanisms through which
Furthermore, GABA treatment increases the activity P mitigates Al toxicity. Under Al stress, notable changes
of key antioxidant enzymes, such as peroxidase and are observed in the morphology and flavonoid content
superoxide dismutase, thereby restoring redox balance. of C. oleifera leaves. Specifically, there is a significant
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Parallel observations have been made in alfalfa, where increase in the total flavonoid content and enhanced
Al stress results in a substantial accumulation of Al ions antioxidant activity in leaf extracts. Flavonoids are
in both root and shoot tissues, subsequently elevating believed to aid in Al detoxification by scavenging ROS
ROS levels and inducing oxidative stress. 16 or forming Al chelates, thereby alleviating the toxic
Phosphorus (P) is a crucial element required for impact of Al on C. oleifera and playing a crucial role in
the growth and development of plants. It is among the the plant’s response to Al toxicity. In addition, research
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Volume 22 Issue 5 (2025) 166 doi: 10.366922/AJWEP025150108