Medicinal Plant Research 2025, Vol.15, No.4, 151-160 http://hortherbpublisher.com/index.php/mpr 155 Supplementation of blue light and red light, can also enhance the accumulation of total flavonoids and polyphenols, thereby improving the medicinal quality of the root system (Ye et al., 2017; Wang et al., 2018; Gam et al., 2020). Metabolomics and transcriptomics studies have found that, there are differences in the flavonoid and diterpenoid metabolite profiles among different organs, and roots show different secondary metabolite accumulation patterns from stems and leaves (Chen et al., 2020; Wei et al., 2022). Flavonoids, phenols, diterpenoids and polysaccharides are not only antioxidant substances, but act as signal molecules, which can enhance the tolerance of root systems, to oxidative stress and abiotic stress (Wei et al., 2022; Yang et al., 2023; Jiang et al., 2025). The accumulation of these compounds, helps alleviate the damage caused by reactive oxygen species (ROS), maintain membrane stability, and enhance the overall stress resistance of plants during the domestication process. For instance, exogenous application of certain flavonoids, such as quercetin, has been proven to enhance antioxidant capacity and physiological indicators (Cui et al., 2023). 4.3 Mineral nutrient uptake and utilization The root systems of A. roxburghii after transplantation, often face nutrient limitations, especially phosphorus deficiency. Studies have shown that, the application of strigolactone can alleviate hypophosphatemia stress by promoting root elongation, reducing oxidative damage, and possibly enhancing phosphorus absorption and utilization (Zhong et al., 2025). Beneficial rhizoidal bacteria and mycorrhizal fungi, can also improve nutrient assimilation efficiency, promote biomass increase and increase the content of active components (Wei et al., 2020; Ye et al., 2020). Calcium and magnesium can help maintain the stability, and function of root cell membranes. Transcriptome data indicate that, calcium ion binding and related pathways are upregulated in response to environmental stimuli, which helps maintain cell wall integrity and participates in signal regulation during root adaptation (Li et al., 2024). These mineral elements, provide structural and functional resilience to root cells, promoting their successful domestication and continuous growth. 5 Phenotypic and Physiological Indicators of Root Recovery 5.1 Root morphological indicators The morphological characteristics of the root system, are the main intuitive indicators for evaluating the root recovery of tissue-cultured A. roxburghii seedlings after transplantation. Studies have shown that, the optimized rooting protocol can achieve a higher number of single bud roots (like 2.62 roots per bud), and a higher rooting rate (92%), and increase root length and root surface area under suitable culture medium and light conditions (Zhang et al., 2025b). The symbiotic relationship between mycorrhizae and endophytic fungi, can further increase the number of roots, root length and overall biomass, reflecting the enhanced adaptability and nutrient absorption capacity of plants (Ye et al., 2020; Zhang et al., 2020a). Microscopic observation of the root tip meristem, can reveal cell activity and the health status of the root system. Healthy meristem, which exhibits active cell division and an orderly tissue structure, is conducive to continuous root elongation and regeneration after transplantation. Immunocytochemical and histological studies have confirmed that, the symbiotic relationship of beneficial microorganisms can promote meristem activity, and root development without causing tissue damage (Ye et al., 2020). 5.2 Root vigor and physiological parameters The triphenyltetrazolium chloride (TTC) reduction assay, is the standard method for evaluating the metabolic activity and vitality of root systems. The high TTC reduction rate indicates vigorous root respiration and strong activity, which is closely related to the successful domestication and growth of A. roxburghii (Wang et al., 2018). Light quality and exogenous treatment, can regulate root activity. For instance, under specific supplementary light conditions, the TTC reduction rate is significantly increased (Wang et al., 2018). The electrolyte leakage test, can be used to measure membrane integrity. A low leakage rate indicates that, the root cell state is relatively healthy. Treatment methods that can alleviate oxidative stress (application of strigolactone or
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