Compared to other salt-tolerant plants or halophytes such as Salicornia L. and Atriplex L., Av is better suited for long-term ecosystem functions, offering deep soil stabilization, bioresource production, and higher phytochemical content (Jiang et al., 2021a; Manzoor et al., 2022; Xie et al., 2012). Table 2 makes this comparison explicit by juxtaposing Av with other halophyte species in terms of (i) tolerated salinity ranges and water requirements, (ii) documented effects on erosion control, soil organic carbon and microbial biomass, and (iii) main harvested products and market uses. In arid landscapes, Apocynum reduces wind erosion and sand drift through its deep (2–3 m) fibrous root systems and dense canopy, making it effective for sand fixation. Field trials in Xinjiang showed wind erosion was reduced by 70–89% in planted plots. When interplanted with Caragana korshinskii Kom., it enhanced soil microbial respiration and promoted rhizosphere symbioses, aiding soil health recovery (Liu et al., 2022; Ping et al., 2014; Sun and Chen, 2025). In desertified zones, soil organic carbon (SOC) increased by 1.2 to 2.8 times compared to bare sand dunes (Li et al., 2022). Its deep roots and litter inputs promote microbial processes such as carbonate precipitation and organic matter stabilization, contributing to soil fertility and structure (Gao et al., 2018b; Li et al., 2021; Wang et al., 2024). In arid landscapes, field studies show that Av plantings substantially reduce erosion, enhance carbon storage, and improve soil condition. In the plain desert of the Altay Region in Xinjiang, planting Av markedly enhanced both carbon storage and erosion control. Plant carbon density increased by about 340% and 460% compared with the plain desert, leading to roughly 21 to 23% higher total ecosystem carbon density. At the same time, wind erosion modulus decreased by about 71 to 89% and soil water erosion by around 14 to 18% in Av plots relative to bare control plots, while surface stability and vegetation cover improved markedly (Ping et al., 2014). Along saline basins and riparian zones in northwestern China, stands of Av and Ap established on degraded or saline soils are reported to have higher soil organic matter and richer soil biota than adjacent uncultivated or conventionally cropped land, highlighting clear soil amelioration benefits in addition to fiber and leaf production (Jiang et al., 2021a, 2021; Thevs et al., 2012; Xiang et al., 2023). At the plant level, experiments under saline–alkali stress show a roughly 40% increase in the root cortex to diameter ratio, about a 100% enlargement of xylem vessel diameter, nearly 70% thickening of phloem fiber walls, and around 50% increases in root soluble sugars and root flavonoid content in Av changes that support more efficient water uptake, salt exclusion, and mechanical stability in degraded soils (Zhang et al., 2025b).

These Apocynum-specific findings are consistent with broader evidence from arid and semi-arid afforestation. A global synthesis of tree and shrub planting on degraded land reports mean increases of about 131% in soil organic carbon stocks and 88% in total nitrogen when barren land is converted to woody vegetation, underlining the potential of perennial halophytes such as Apocynum to act as soil-carbon sinks while restoring fertility (Liu et al., 2018). From a climate and resource-use perspective, life-cycle assessment indicates that cotton fiber in China has a climate footprint of about 4.43 kg CO₂-equivalents per kilogram and a phosphorus footprint near 101 g P kg⁻¹, whereas Apocynum fiber can be produced at roughly 1.93 kg CO₂-equivalents and 1.6 g P kg⁻¹, suggesting large potential savings in greenhouse gas emissions and nutrient pollution if Apocynum partially substitutes cotton in Xinjiang (Günther et al., 2017). Farm-level economic analysis along the Tarim Basin further shows that Ap cultivation requires about 16,250 yuan ha⁻¹ in costs, generates around 49,000 yuan ha⁻¹ in revenue, and yields profits near 32,800 yuan ha⁻¹, outperforming cotton and Chinese red date under comparable conditions (Rouzi et al., 2017). Taken together, these quantitative data demonstrate that Apocynum-based systems can simultaneously deliver windbreak and sand-fixation services, enhance soil carbon and nutrient stocks, and provide economically competitive fiber and leaf production in arid, saline landscapes. The next section, comparative genomics and traits of Apocynum species, compares the genomic and physiological capacities that underlie these field outcomes.

Av and Ap are the best studied in the genus, with evidence for phytoremediation, medicinal use, and bast fiber quality (Jiang et al., 2021a; Xiang et al., 2023). Chloroplast genome analyses reveal high conservation between Av and Ap, both having plastid genomes of ~150,800 bp in size and sharing the same number of protein-coding genes (86), though Ap contains more SSRs, indicating greater organelle-level variability (Guo et al., 2022; Zheng et al., 2022). Available nuclear assemblies report ~23,147 predicted protein-coding genes in Ap versus ~20,292 in Av, with more than 91% of models functionally annotated; counts may vary with assembly completeness and annotation pipelines (Xie et al., 2024b). Comparative stress-response genomics show that Av upregulates flavonoid biosynthesis genes such as AvFLS and AvF3H, while Ap relies on a broader network of WRKY transcription factors (Xie et al., 2024b; Zhang et al., 2023). Building on the plastome and nuclear patterns already noted, independent datasets suggest the two species rely on different levers when salinity coincides with osmotic limitation. In Av, salt stress elevates phenylpropanoid and flavonoid enzyme activity, including AvF3H and AvFLS, which strengthens antioxidant capacity and helps protect membranes (Li et al., 2023a; Zhang et al., 2023). By contrast, the Ap genome reports an expanded set of regulators and broad induction of WRKY transcription factors under water-related stress, consistent with faster reprogramming of ion transport and osmolyte balance (Xie et al., 2024a). Physiologically, Av demonstrates higher photosynthetic performance (12–18 μmol CO₂ m^-2 s^-1) and superior water-use efficiency compared to traditional crops like cotton (Cui et al., 2019; Li et al., 2023a). Both Av and A. pictum show notable phytoremediation capacity, including lithium uptake from contaminated soils (Jiang et al., 2018; Xiang et al., 2023). Bast fibers from Av have higher tensile strength (450–600 MPa), and its leaves contain elevated levels of bioactive compounds like quercitrin and hyperoside, contributing to superior antioxidant potential (Chan et al., 2015; Gao et al., 2019a; Shao et al., 2022). These biochemical traits correlate with differential expressions of phenylpropanoid pathway genes (Chen et al., 2023, 2020; Dorjee et al., 2024). These patterns translate into ecosystem effects only when stress is active in the field, so the next subsection evaluates contributions to climate mitigation and soil remediation.

Halophyte plantings on degraded soils commonly can reduce wind erosion, improve soil organic matter, and support richer microbial communities (Hu et al., 2024; Li and Liu, 2020; Wang et al., 2021). Increased evapotranspiration from halophyte vegetation can also contribute to local cooling in arid environments (Freedman et al., 2014). Where persistent cover is achieved, Apocynum may show comparable outcomes and thus support United Nations SDG 13 (Climate Action) alongside land-restoration goals. Figure 2 synthesizes these pathways for Apocynum by diagramming how deep rooting, litter inputs and rhizosphere processes drive carbon sequestration and soil restoration, while ion uptake and vacuolar sequestration underpin phytoremediation of Na⁺ and Li⁺. The figure also summarizes how these biophysical functions may translate into biodiversity support and climate-risk reduction at the landscape scale. Av deep root systems help secure water during dry periods and play a role in enhancing soil stability and preventing erosion in arid lands (Jiang et al., 2021a; Wu et al., 2022; Xiang et al., 2023), supporting SDG 2 (Zero Hunger) by improving soil productivity. Beyond physical stabilization, Av and Ap exhibit phytoremediation potential. These species accumulate toxic ions like Na⁺ and Li⁺ without compromising growth, transporting them to vacuoles via membrane transporters. Root uptake and leaf compartmentalization have been documented with bioconcentration factors (BCF) and translocation factors (TF) >1, confirming their value for salt and lithium-contaminated soil remediation (Jiang et al., 2019, 2018, 2021; Kot, 2018; Li et al., 2023a; Qiao et al., 2018), further advancing SDG 15 (Life on Land). Given these regulating services, it is important to assess market and public-health value, so the next subsection summarizes economic and health benefits.

Economically, Apocynum bast fibers contain 65–75% cellulose and low lignin, yielding high mechanical performance, with tensile strength up to 401.56 cN dtex⁻¹, surpassing cotton and flax (Jiang et al., 2021b; Lou et al., 2020). Its fibers are used in eco-textiles and composites (Chen et al., 2022; Xu et al., 2020a). Because Apocynum can be cultivated on non-arable land, it offers income opportunities without competing with food crops (Thevs et al., 2012; Xiang et al., 2023). Additionally, specialty honey derived from Apocynum nectar shows broad-spectrum antimicrobial and antioxidant activity, with more than 85% inhibition against E. coli and S. aureus (Arunasree et al., 2024; Xiang et al., 2023), supporting applications in wound care, functional foods, and therapeutic products (Al-Kafaween et al., 2023; Dahiya et al., 2024). Flavonoid-rich tea and extracts, containing rutin and quercetin, are reported to provide neuroprotective, hepatoprotective, and cardioprotective benefits (Jiang et al., 2019; Xie et al., 2024b; Zeng et al., 2022). Taken together, these outcomes support SDGs 1, 2, 3, 9, and 12. Recognizing Apocynum’s ecological and economic significance, the following section details its specific contributions to key SDGs, particularly in the context of land restoration and climate action. To connect products with sustainability outcomes, the final subsection outlines circular bioeconomy strategies that reduce waste and raise resource efficiency.

In addition to their ecological and agronomic contributions, Apocynum species, especially Av can contribute to SDG 12 (Responsible Consumption and Production) when circular practices are applied, for example full-plant valorization of stems for fiber, leaves for standardized extracts, and residues for energy or biochar, with water reuse where feasible. The entire plant can be utilized to generate high-value products while enhancing carbon sequestration and minimizing waste (Jiang et al., 2021a, 2021; Rouzi et al., 2017; Thevs et al., 2012; Xiang et al., 2023). For instance, cellulose-rich stems can be converted into textiles or nanocellulose composites, and flavonoid-rich leaves into pharmaceutical extracts (Dorjee et al., 2024; Shao et al., 2022). Residual biomass can undergo anaerobic digestion or pyrolysis to produce biochar, which at 10–20 t/ha can sequester carbon for centuries and improve soil water retention by 15–20% (Ali and Al-Wahaibi, 2025; Jiang et al., 2025a; Kabir et al., 2023; Khan et al., 2024; Kocsis et al., 2022; Ndede et al., 2022). Deep root systems complement this by contributing to belowground carbon sinks (Buss et al., 2021; Kell, 2011). Wastewater from fiber extraction, which is rich in residual polyphenols, can be treated with biochar filtration to recover polyphenols by adsorption onto the biochar followed by solvent or mild alkaline desorption, enabling water reuse and sorbent regeneration (Abid et al., 2022; Dahani et al., 2025; El Barkaoui et al., 2025; Olugbenga et al., 2024; Wang et al., 2022). Such circular processes enhance the role of Apocynum-based systems as nature-based solutions, integrating environmental sustainability with resource efficiency. The resulting closed-loop system maximizes resource efficiency and reduces environmental impact core priorities under SDG 12 (Cho et al., 2024; Olugbenga et al., 2024). Applied studies on Salicornia highlight product safety and processing considerations for edible shoots, which are relevant to Apocynum supply-chain design (Marangi et al., 2024).

Av demonstrates multifaceted tolerance to salinity through a coordinated interplay of ion transport regulation, antioxidant defense, osmotic adjustment, and gene expression reprogramming. Apocynum responses to salinity have been quantified under controlled assays, which helps interpret the signaling steps involved. At the seed stage, NaCl treatments from 0 to 300 mmol L⁻¹ produced clear, dose-dependent shifts: activities of SOD, POD, and CAT increased up to about 150 mmol L⁻¹ and then declined toward 300 mmol L⁻¹, while APX increased across the entire range; soluble sugar, malondialdehyde, and proline contents increased with rising NaCl, and protein content decreased at higher concentrations, all measured after short-term germination assays (Li et al., 2023c). Seedling and hydroponic studies report consistent patterns at 100 to 350 mmol L⁻¹ NaCl, including elevated root SOD and CAT and transcriptome enrichment for MAPK, phytohormone signaling, ion transport, and cell-wall processes. Typical assay ranges are 0, 100, 200, and up to 350 mmol L⁻¹ NaCl with ~7-day exposure after a short ramp (Li et al., 2023c; Xu et al., 2021). Salt also induces the flavonoid pathway, with increased expression of AvF3H and AvFLS and higher flavonol accumulation linked to improved salt tolerance in heterologous tests (Zhang et al., 2023). A critical component of this adaptation is the maintenance of Na⁺/K⁺ homeostasis, which mitigates ion toxicity and preserves cellular function. Under saline conditions, Na⁺ competes with K⁺ for binding sites and enzymatic cofactors, impairing protein function, membrane potential, and photosynthesis (Cheeseman, 2013; Zhao et al., 2020). While Na⁺ can serve a limited osmotic function, excessive accumulation is toxic and must be tightly regulated. Studies in Apocynum reveal that Na⁺ content significantly increases in roots, stems, and leaves under prolonged salt stress. However, salt-tolerant species like Ap maintain a higher K⁺/Na⁺ ratio under control conditions, though this advantage declines with increasing salinity (Gao et al., 2023a; Xu et al., 2021). Interestingly, tetraploidy in Av does not significantly alter ion distribution patterns, contrasting with species like Zoysia japonica Steud. or Lycopersicon pennellii (Correll) D’Arcy, suggesting a distinct regulatory mechanism in Apocynum (Li et al., 2023d; Tahal et al., 2000). Key insights from hydroponic experiments indicate that cultivation method and stress duration significantly influence ion profiles Apocynum grown under uniform, long-term salt exposure displayed consistent Na⁺ accumulation trends, reflecting field-relevant stress physiology (Xu et al., 2021). Moreover, Apocynum appears to prefer vacuolar sequestration of Na⁺ mediated by tonoplast-localized transporters like Av Na⁺/H⁺ antiporter 1 (AvNHX1) as a strategy to reduce cytosolic toxicity while maintaining osmotic balance (Bai et al., 2023; Qin et al., 2024; Waheed et al., 2024). Across halophytes, coordination between HKT1 transporters and SOS signaling helps maintain K⁺ to Na⁺ homeostasis, consistent with ion-balance responses reported for Apocynum (Hualpa-Ramirez et al., 2024; Zhou et al., 2024). Across osmotic and saline conditions, Av maintains effective K⁺ uptake; added NaCl raises leaf Na⁺ for osmotic adjustment while K⁺ remains the main contributor, supporting photosynthesis and growth (Cui et al., 2019). In model plants, root HKT1 limits Na⁺ movement to shoots and NHX1 sequesters Na⁺ in vacuoles, helping sustain lower Na⁺:K⁺ ratios (Abdelaziz et al., 2017; Almeida et al., 2017; Liu et al., 2025; Wang et al., 2019). Consistent with this response in Av, NAC genes such as AvNAC58 and AvNAC69 show strong tissue-specific induction near 200 mM NaCl (Huang et al., 2023).

A crucial molecular regulator of Na⁺ and K⁺ dynamics is the high-affinity potassium transporter gene ApHKT1. Functional studies revealed that ApHKT1 expression is highest in roots under mild salinity (50 mM NaCl) and is lower at 100–200 mmol L⁻¹ in seedling or hydroponic time courses (Assaha et al., 2017; Gao et al., 2023a; Xu et al., 2021), which strongly correlates with salt tolerance across Apocynum species. Salt-tolerant Ap, for example, displays higher root expression of ApHKT1 under mild stress, facilitating controlled Na⁺ exclusion and K⁺ retention, while sensitive species exhibit reduced expression and greater Na⁺ accumulation in leaves, correlating with higher toxicity (Assaha et al., 2017; Xu et al., 2021). With increased salt concentrations (100–200 mM NaCl), ApHKT1 expression is progressively suppressed particularly in roots indicating an adaptive mechanism to limit Na⁺ influx during severe stress. The spatial expression gradient of ApHKT1 higher in roots and lower in leaves/phloem helps limit Na⁺ transport to aerial tissues, protecting photosynthetically active cells from ion overload (Gao et al., 2023a). Supporting this are coordinated upregulations of other ion-related genes, including TPK1, HAK, and SOS2 (Salt Overly Sensitive 2), which enhance K⁺ uptake and Na⁺ exclusion, stabilizing ion ratios under stress (Zhao et al., 2025). The role of SOS signaling is particularly relevant here: it operates in parallel with ApHKT1 to prevent Na⁺ cytotoxicity and preserve membrane potential (Wang et al., 2019; Xu et al., 2021; Zhao et al., 2025). These findings align with mechanisms described in Arabidopsis thaliana, Triticum aestivum, and Oryza sativa, but show species-specific modulation in Apocynum (Gholizadeh et al., 2024). In conjunction with ion regulation, Av mobilizes antioxidant defenses under salinity, increasing activities of enzymes such as SOD, CAT, and POD, and accumulating osmoprotectants like proline and soluble sugars. Furthermore, flavonoid biosynthesis is upregulated through genes such as AvFLS and AvF3H, which enhance quercetin and kaempferol levels molecules known for their dual function as antioxidants and signaling regulators (Wang et al., 2021; Zhang et al., 2023). Overexpression of AvFLS in tobacco increased total flavonoids and improved salt-stress performance, while heterologous expression of AvF3H, AvF3′H, and AvFLS in Arabidopsis elevated total flavonoids and rutin and enhanced salt-tolerance readouts (Wang et al., 2021; Zhang et al., 2023). Altogether, salinity tolerance in Av arises from a network of root-localized Na⁺ transport suppression (via ApHKT1), vacuolar sequestration (AvNHX1), K⁺ homeostasis (TPK1, HAK), ROS scavenging (SOD, flavonoids), and osmotic balance (proline, sugars), all underpinned by hormone signaling and transcription factor activation (Zhao et al., 2025). This multilayered mechanism positions Av as a promising model for breeding or engineering salt-tolerant crops for marginal lands.

Av demonstrates a remarkable capacity to tolerate drought through a combination of morphological plasticity, physiological regulation, and stress-responsive gene networks that together maintain cellular homeostasis and water-use efficiency. Morphologically, the species develops deep and extensive root systems capable of penetrating lower soil layers to access subsurface moisture reserves, a trait critical for sustaining water uptake during extended dry periods (Li et al., 2023a; Thevs et al., 2012; Xiang et al., 2023). Concurrently, its leaves exhibit xeromorphic features such as thickened cuticles, dense wax layers, and sunken stomata that minimize transpirational water loss. These sclerophyllous leaf traits, often accompanied by heliotropic reorientation, help reduce solar exposure and thermal stress under arid conditions (Abubakar et al., 2022; Cui et al., 2019; Jiang et al., 2021a). At the physiological level, Av maintains photosynthetic activity during water scarcity through rapid and reversible stomatal closure, which limits transpiration while protecting the integrity of the photosynthetic apparatus (Pradhan et al., 2025; Wu et al., 2022). The plant performs osmotic adjustment by accumulating compatible solutes such as proline and soluble sugars, which function to stabilize osmotic potential, preserve membrane structure, and protect cellular proteins (Parvin et al., 2025; Zhao and Dai, 2015). These osmolytes also serve as metabolic reservoirs during recovery from dehydration. Under seedling drought assays, SOD, POD, and CAT activities rise relative to controls, with APX increases reported where assayed in Av (Iqbal et al., 2023; Li et al., 2023c; Wu et al., 2022). Similar antioxidant trends under water deficit are also noted by Iqbal et al. (2023). Together, osmotic regulation and ROS scavenging enhance cellular resilience during desiccation. Comparative halophyte studies show that drought and salt interact to shape gas exchange, ionic balance, and antioxidant capacity, aligning with the Apocynum responses (Muhammad et al., 2024; Zandalinas and Mittler, 2022).

Beyond metabolic adjustments, Apocynum modulates gas exchange and water use under drought. In seedlings exposed to PEG near −0.2 MPa, supplying 25 mM NaCl kept leaf K as the main contributor to osmotic potential, improved relative water content, and supported higher photosynthetic activity, consistent with tighter control of stomatal conductance under water deficit (Cui et al., 2019). Water-use efficiency in this review refers to A_n/g_s, where A_n is the leaf net CO₂ assimilation rate and g_s is stomatal conductance to water vapor; units are µmol CO₂ m⁻² s⁻¹ for A_n and mol H₂O m⁻² s⁻¹ for g_s, so A_n/g_s has units µmol CO₂ per mol H₂O (Busch et al., 2024; Seibt et al., 2008). This framing highlights the role of stomatal kinetics: faster opening raises carbon gain when light increases, whereas rapid closure conserves water during declines or transient stress (Bertolino et al., 2019; Lawson and Vialet-Chabrand, 2019). At the whole-plant scale, root phenotypes that combine lower root hydraulic conductance with longer axes and dense root hairs can delay soil limitation and sustain transpiration in drying soils, providing a useful lens for interpreting Apocynum drought performance (Cai et al., 2022).

Hormonal signaling, particularly via abscisic acid (ABA), plays a central role in coordinating drought responses in Av. ABA not only promotes stomatal closure to conserve water but also induces the formation of deeper root systems that improve access to soil water (Cui et al., 2019; Xu et al., 2018). This dual function enhances both short-term drought avoidance and long-term drought tolerance. Additionally, the plant exhibits elevated accumulation of stress-related flavonoids (e.g., hyperoside, quercitrin), which act as non-enzymatic antioxidants and modulators of stress signaling pathways (Chan et al., 2015; Shao et al., 2022; Xu et al., 2020b). These specialized metabolites increase during drought, especially in leaf tissues, contributing to both ROS detoxification and membrane stabilization. Molecular analyses further reveal the complexity of Av drought response. Transcriptome profiling under PEG-induced drought stress during germination has identified differentially expressed genes involved in hormone signaling (ABA, gibberellins, auxin, ethylene), cellular detoxification, and transcriptional regulation (e.g., WRKY, NAC, MYB) (Wu et al., 2022; Zhang et al., 2025a). Key upregulated genes such as GASA4, PP2CA, and EIN3 mediate hormonal crosstalk that fine-tunes root development, leaf growth suppression, and stomatal behavior. This coordinated gene regulation supports physiological resilience during early developmental stages and enables successful seedling establishment under drought conditions. Importantly, Av also reallocates resources under drought stress, shifting biomass toward lignified stems and deeper roots while reducing leaf expansion and shoot elongation. This redistribution enhances mechanical support, reduces water demand, and prioritizes resource acquisition and storage in roots traits particularly valuable for perennial species in arid regions (Jiang et al., 2021a; Li et al., 2023a). Taken together, these interconnected drought tolerance mechanisms ranging from structural traits to metabolite synthesis and gene regulation demonstrate how Av thrives in marginal ecosystems and reinforces its suitability for ecological restoration and low-input cultivation in arid lands.

Recent omics syntheses indicate that combined stresses rewire networks rather than simply add single-stress effects, which helps interpret Apocynum responses under concurrent drought and salinity (Khan et al., 2025; Secomandi et al., 2025; Zandalinas and Mittler, 2022). In arid and semi-arid regions, plants are frequently exposed to simultaneous drought and salinity stress, which together impose osmotic imbalance, ion toxicity, and oxidative stress. Av has evolved a highly integrated and dynamic defense system that enables it to cope with such combined abiotic stress. These stressors act synergistically to disrupt water uptake, impair Na⁺/K⁺ balance, and induce the generation of reactive oxygen species (ROS), collectively threatening cellular integrity and metabolic function (Cheeseman, 2013; Zhao et al., 2020, 2025). Figure 3 provides an integrated overview of these responses in Av, linking root and shoot traits, osmotic adjustment, antioxidant activity and ion homeostasis to whole-plant performance under dual stress. Building on the individual tolerance mechanisms described in the previous sections, the figure emphasizes cross-protective strategies such as coordinated ABA signaling, vacuolar Na⁺ sequestration and flavonoid accumulation that underpin survival and persistence in marginal ecosystems. The morphological foundation of Av stress resilience namely, deep and fibrous root systems, sclerophyllous leaves, thick cuticles, and sunken stomata remains essential under combined stress (Jing et al., 2024). These traits, previously highlighted under both drought and salinity responses, are further reinforced by adaptive heliotropic leaf reorientation and biomass allocation favoring lignified stems and root tissues. Such structural plasticity enhances subterranean water extraction while reducing irradiance exposure and evaporative water loss (Cui et al., 2019; Jiang et al., 2021a; Li et al., 2023c; Wu et al., 2022).

Physiologically, Av exhibits intensified osmotic adjustment through elevated proline and soluble sugar accumulation, which stabilizes cell turgor and protects cellular macromolecules under combined osmotic and ionic stress. These osmolytes also support continued metabolic function during dehydration. Concurrently, the enzymatic antioxidant machinery comprising SOD, POD, CAT, and APX works in concert with non-enzymatic antioxidants (e.g., flavonoids) to detoxify ROS generated by dual stress exposure (Li et al., 2023c; Wu et al., 2022). As previously detailed, these mechanisms are central to Av oxidative stress tolerance under individual stress conditions, but under combined drought and salinity they are co-activated at higher magnitude and with longer duration. Hormonal pathways, especially ABA, continue to serve as the principal signal integrators during combined stress. ABA promotes rapid stomatal closure, enhances root elongation, and activates downstream transcription factors and stress-inducible genes. In addition to ABA, jasmonic acid, ethylene, and auxin pathways further modulate cell wall remodeling, antioxidant gene expression, and growth suppression under combined stress, amplifying the fine-tuned crosstalk described in the drought section (Cui et al., 2019; Xu et al., 2018; Zhang et al., 2023).

The viability of Apocynum, particularly Av, in harsh, saline, and low-fertility soils is well established (Jiang et al., 2021b; Li et al., 2023b; Xiang et al., 2023). Native to Eurasia and North America, it thrives in degraded, saline-alkaline, and sandy soils (Jiang et al., 2021a, 2021b). Field trials in Xinjiang confirm its minimal irrigation requirements under <300 mm rainfall (Gao et al., 2018a, 2018; Jiang et al., 2021a, 2021; Ma et al., 2024; Xiang et al., 2023; Zhang et al., 2022a, 2022). Av and Ap tolerate salinity and grow well where conventional crops fail (Gao et al., 2023b). Seeds germinate optimally at 25–30°C (Rong et al., 2015), and can establish under drought or salinity (Jiang et al., 2021a). Unlike cotton, Av survives on groundwater (Thevs et al., 2012). Supplemental irrigation boosts yields in coarse soils (Gao et al., 2023b). Drip irrigation every 7 days improves water-use efficiency (Gao et al., 2023b). PEG-induced drought simulations enhanced seedling performance (Wu et al., 2022). While suited to nutrient-poor soils, balanced fertilization (34.8 kg/ha N, 57.2 kg/ha P) boosts biomass and flavonoids (Li et al., 2023b). Both Av and Ap show phytoremediation capacity (Chen et al., 2020; Jiang et al., 2021a; Li et al., 2023a, 2023, 2023), with dual outputs of fibers and bioactive compounds (Prates‐Valério et al., 2019). Compared to jute, hemp, and cotton, Apocynum offers greater resilience, lower inputs, and dual-purpose utility (Chen et al., 2022; Xiang et al., 2023; Xie et al., 2024b). Its cultivation is suitable for saline regions and climate-adapted systems (Cui et al., 2019; Günther et al., 2017). Its ecological advantages and economic returns make it a model crop for sustainable bioeconomies (Jiang et al., 2021b; Li et al., 2023b; Rouzi et al., 2017; Wang et al., 2007). These foundational insights into site-specific cultivation guide the selection of practical propagation techniques suited for stress-prone environments. For propagation planning, Kanuma soil is optimal for cutting propagation, while saline and saline-alkali soils are highly suitable for field establishment and seed or rhizome propagation of Apocynum species (Jiang et al., 2018, 2021; Seo et al., 2023). Av is supported for high fiber and leaf-flavonoid production on sandy to sandy-loam saline or saline-alkaline soils, with successful field management under drip irrigation (Gao et al., 2018a, 2018) and improved leaf yield and quality under balanced fertilization (Gao et al., 2019a, 2019; Li et al., 2023b; Xiang et al., 2023). Ap fits sites where salinity fluctuates or where lithium occurs, with demonstrated Li accumulation and growth on alkaline, low-organic-matter desert topsoil (Jiang et al., 2018). Ap is a strong option for higher-salinity or saline-alkali flats and saline-soil improvement, supported by comparative genome-metabolome evidence for stress-tolerance modules relevant to restoration (Jiang et al., 2021b; Li et al., 2023a).

Propagation techniques include direct sowing, rhizome propagation, cuttings, and transplanting. Direct sowing is cost-effective and beneficial for desertification control but is limited by environmental stress (Jiang et al., 2021a, 2021). Adverse rainfall may hinder germination (Gavric and Omerbegovic, 2021). Though transplanting has better seedling establishment, it’s more labor-intensive (Caporale et al., 2022; Turebayeva et al., 2022). Rhizome propagation supports stress resilience (Jiang et al., 2021a) but requires careful handling (Gao et al., 2019b). Cutting propagation, especially in A. lancifolium, performs well with Kanuma soil and IBA treatments (Seo et al., 2023; Zhou et al., 2021), supporting mass propagation (Turebayeva et al., 2022). Transplanting nursery-raised seedlings with optimized substrate and NPK pre-treatment enhances establishment (Kyalo et al., 2020; Oyedeji et al., 2014; Reis et al., 2025). These complementary techniques enable scalable and sustainable cultivation under arid stress. A clear understanding of the agricultural cycle and harvesting windows is also essential to maximize both ecological services and economic returns. Table 3 collates this practical information by contrasting seed, rhizome, cutting and transplant-based propagation systems, the associated substrate and irrigation requirements, and the recommended harvest stages for fiber and leaf biomass. The table is intended as a decision-support tool for selecting site-appropriate cultivation strategies in saline and drought-prone environments.

Field and system-level work in other halophytes offers practical guides for saline agriculture, from Salicornia aquaculture integration to Atriplex forage and phytoremediation trials (Giménez et al., 2024; Kachout et al., 2025). Apocynum species regenerate annually from rhizomes. Sowing starts in mid-spring, with seed germination optimized under 10/25°C to 15/30°C (Jiang et al., 2021a; Li et al., 2023b; Wu et al., 2022). Shoot emergence occurs by March–April (Abubakar et al., 2022). Their tolerance to stress is linked to redox balance and flavonoid accumulation (Jiang et al., 2021b; Tan et al., 2024). Full establishment may take two years, after which regular harvesting begins (Jiang et al., 2021b). The perennial life cycle includes flowering (June–August) and fruiting (September–October). Flavonoids peak in August, making it ideal for medicinal harvest (Jiang et al., 2021b; Shao et al., 2022; Xiang et al., 2023). Fiber is harvested in late summer or winter, reaching peak yield in the third year and maintaining productivity for up to a decade (Abubakar et al., 2022; Rouzi et al., 2017; Thevs et al., 2012; Zhao et al., 2024). Hairy root systems in vitro allow flavonoid production within 30 days (Zhang et al., 2022a). Variability among genotypes affects fiber and leaf yield, suggesting opportunities for further optimization (Zhao et al., 2024). With optimized cultivation in place, exploring genomic diversity and functional traits can accelerate breeding for improved stress resilience and productivity.

Despite growing recognition of Apocynum for arid ecosystems, several barriers limit scale-up. Agronomically, there are no optimized management packages for diverse dryland environments, and multi-location trials beyond China are scarce. Mechanization is limited. Genetically, within- and across-species variation is poorly characterized, which restricts breeding for fiber yield, flavonoid content, and phytoremediation capacity. Propagation and cultivation protocols are not standardized or cost-effective across site types, constraining scalability. Evidence on stress tolerance remains fragmented across studies, with weak links from physiology and molecular markers to field performance. Gene-editing tools such as CRISPR require species-specific protocols, biosafety assessment, and regulatory pathways before routine use.

Priorities include chromosome-level assemblies for key species, tissue- and stage-specific transcriptomes under single and combined stresses, and network inference that connects transcription factors to ion transporters and flavonoid enzymes. Community benchmarks should report effect sizes and fold-changes under clearly defined salinity and drought regimes, with shared metadata and code for reproducibility. Comparative genomics across Av, Ap, and other Apocynum species can identify conserved and lineage-specific stress modules to guide marker development.

Field protocols should test sowing windows, saline irrigation thresholds, and deficit-irrigation schedules across soils, with standard reporting of K⁺ to Na⁺ ratios, water-use efficiency, survival, and yield. Validate low-cost establishment at scale, including intercropping on dunes, living windbreaks, and residue management. Evaluate biochar, Plant growth-promoting rhizobacteria (PGPR), and nanoparticle seed treatments side-by-side in common trials that track fiber quality and bioactive profiles, while monitoring safety and environmental compatibility.

Develop full-plant biorefinery pathways: stems to technical fiber or nanocellulose, leaves to standardized flavonoid extracts, residues to energy or biochar. Report cradle-to-gate metrics for carbon storage, water use, and unit costs to benchmark Apocynum against existing crops. Build supply-chain pilots with quality standards for fiber and phytochemicals and explore under-studied metabolites such as isoquercitrin for pharmaceutical and nutraceutical markets. Market entry can begin with a focused bundle that includes technical fiber specifications for textiles and composites, standardized leaf-extract profiles for flavonoids, and verified biomass for restoration or remediation contracts. Early pilots can reduce risk by using offtake agreements with local processors, small purchase guarantees for first harvests, and quality-testing hubs that issue lot certificates and price to quality.

Focus on varietal registration and certified seed systems, extension packages for saline and arid zones, and incentives that reward restoration outcomes, together with product value. Align land-use rules to favor planting on marginal lands without competing with food crops, and support regional processing hubs to reduce transport costs. Pilot data-driven programs that pair ecological indicators with household income metrics to test adoption at the community scale. Implementation often stalls due to fragmented permits, unclear land tenure, and limited saline-agriculture services. A practical path is community-based adoption that registers genotype-specific seed, trains local nurseries for cutting and rhizome supply, and pairs producer groups with extension agents delivering one management package per soil class. Provincial programs can lower barriers with small matching grants for drip kits, shared retting or drying facilities, and outcome payments tied to verified fiber quality, leaf-flavonoid standards, or land-stabilization indicators.