Figures (1)  Tables (2)

    • Figure 1. 

      Mechanistic insights into how beneficial microbes enhance medicinal plant resilience to abiotic stress.

    • Stress type Strain/microbes Medicinal plant Mechanistic function Ref.
      Drought AMF Pelargonium graveolens, Glycyrrhiza uralensis; Camellia sinensis Activation of antioxidant systems Xie et al.[54]; Amiri et al.[55]; Wang et al.[56]
      Poncirus trifoliate; Osmotic regulation Wu et al.[57]
      Nicotiana tabacum;
      Cinnamomum migao      		 Activation of antioxidant systems;
      osmotic regulation      		 Begum et al.[58];
      Yan et al.[59]
      Ephedra foliata Boiss Activation of antioxidant systems; osmotic regulation; regulating IAA, GA and ABA levels Al-Arjani et al.[60]
      Poncirus trifoliate; Regulating root development;
      regulating IAA and ABA levels      		 Liu et al.[61];
      Zhang et al.[62]
      Glycyrrhiza uralensis Regulating aquaporin expression; regulating ABA level Xie et al.[63]
      DES
      		 Lycium ruthenicum, Glycyrrhiza uralensis Regulating root development, nutrient uptake and regulating soil microbiome assembly He et al.[20]; He et al.[64]; He et al.[65]
      Glycyrrhiza uralensis Regulating IAA production and ACCD activity Ahmed et al.[66]
      DSE+ Trichoderma viride Astragalus mongholicus Regulating soil microbial assembly He et al.[67]
      Bacillus sp. Glycyrrhiza uralensis; Activation of antioxidant systems Xie et al.[68]
      Bacillus sp. Trigonella foenum-graecum Enhancing ACCD activity;
      beneficial microbial colonization      		 Barnawal et al.[69]
      Bacterial combination/
      syncoms      		 Astragalus mongholicus Activation of antioxidant systems Lin et al.[70]
      Mentha piperita; Hyoscyamus niger Activation of antioxidant systems Chiappero et al.[71]; Ghorbanpour et al.[72]
      Mentha pulegium Activation of antioxidant systems;
      regulation of ABA and flavonoid levels      		 Asghari et al.[73]
      Ociumum basilicm Osmotic regulation Heidari et al.[74]
      AM fungi and PGPB Lavandula dentata Regulation of IAA levels and ACCD activity Armada et al.[75]
      Trigonella foenum-graecum Activation of antioxidant systems; osmotic regulation; regulation of JA levels Yue et al.[76]
      Echinacea purpurea Regulation of nutrient uptake Attarzadeh et al.[77]
      Glycyrrhiza Regulation of nutrient uptake; beneficial microbial colonization Hao et al.[78]
      Myrtus communis Regulation of nutrient uptake; antioxidant system activation Azizi et al.[79]
      Salt stress AMF Chrysanthemum morifolium Regulation of nitrogen uptake Wang et al.[80]
      Ocimum basilicum Activation of antioxidant systems; osmotic regulation; regulation of the K+/ Na+ ratio Abd-Allah and Egamberdieva[81]
      Trifoliate orange Enhanced aquaporin expression Cheng et al.[82]
      Ocimum basilicum Activation of antioxidant systems Yilmaz et al.[83]
      DES Artemisia ordosica Activation of antioxidant systems; IAA production; regulation of the K+/ Na+ ratio Hou et al.[84]
      Trichoderma asperellum; Priestia endophytica Lycium chinense;
      Trigonella foenum-graecum      		 Regulating nitrogen uptake and assimilation Yan et al.[85];
      Sharma et al.[86]
      Streptomyces sp. Glycyrrhiza uralensis Activation of antioxidant systems Li et al.[87]
      Glutamicibacter sp. Limonium sinense Activation of antioxidant systems; osmotic regulation; regulation of the K+/ Na+ ratio; promotion of flavonoid synthesis Qin et al.[88]
      Bacillus sp.;
      Streptomyces sp.; Azotobacter sp.      		 Limonium sinense; Glycyrrhiza glabra; Iranian Licorice Activation of antioxidant systems; osmotic regulation; regulation of the K+/ Na+ ratio Xiong et al.[39];
      Qin et al.[89];
      Mousavi et al.[90];
      Mousavi et al.[91]
      Paenibacillus sp. Panax ginseng Activation of antioxidant systems; osmotic regulation; regulation of ABA level Sukweenadhi et al.[92]
      Achromobacter sp. Catharanthus roseus Activation of antioxidant systems;
      enhanced ACCD activity      		 Barnawal et al.[93]
      Brachybacterium sp. Chlorophytum borivilianum Regulation of IAA level, ABA level and ACCD activity Barnawal et al.[94]
      Bacterial combination/ Syncoms Bacopa monnieri; Galega officinalis Regulation of the K+/ Na+ ratio Pankaj et al.[95]; Egamberdieva et al.[96]
      Phyllanthus amarus;
      Coriandrum sativum      		 Activation of antioxidant system Joe et al.[97];
      Al-Garni et al.[98]
      Bacopa monnieri; Salicornia sp.; Capsicum annuum Osmotic regulation Bharti et al.[99]; Razzaghi Komaresofla et al.[100];
      Sziderics et al.[101]
      Coriandrum sativum Regulation of the K+/ Na+ ratio;
      activation of antioxidant systems      		 Rabiei et al.[102]
      Glycyrrhiza uralensis Activation of antioxidant systems;
      regulation of nutrient uptake      		 Egamberdieva et al.[103]
      Mentha arvensis Activation of antioxidant systems; regulation of nutrient uptake; regulation of the K+/ Na+ ratio; regulation of ACCD activity and siderophore production Bharti et al.[104]
      Medicago sativa Regulation of the IAA level Saidi et al.[105]
      Pistacia vera Regulation of the K+/ Na+ ratio; regulating IAA level, ACCD activity and siderophore production Khalilpour et al.[106]
      Fungi and PGPB Ocimum sanctum Activation of antioxidant systems;
      regulation of the ACCD activity      		 Singh et al.[107]
      Acacia gerrardii Regulation of the nutrient uptake;
      regulation of the K+/ Na+ ratio      		 Hashem et al.[108]
      Artemisia annuaitalic;
      Sesamum indicum      		 Activation of antioxidant systems; osmotic regulation Arora et al.[109]; Khademian et al.[110]
      Heavy metal stress Halomonas sp Ligusticum chuanxiong Reduction of the heavy-metal uptake and regulating rhizosphere microbial assembly Li et al.[111]
      Piriformospora sp. Piriformospora indica Improving tolerance; regulation of rhizosphere microbial assembly Rahman et al.[112]
      Rhizobia Robinia pseudoacacia Improving tolerance;
      regulation of rhizosphere microbial assembly      		 Fan et al.[113]
      Sphingomonas sp. Sedum alfredii Activation of antioxidant systems Pan et al.[114]
      Burkholderia sp. Sedum alfredii Regulating translocation ability Chen et al.[115]
      Leifsonia sp. Camellia sinensis Regulation of rhizosphere microbial assembly Jiang et al.[116]
      Pseudomonas sp. Solanum nigrum Regulation of nutrient uptake; recruiting beneficial bacteria Chi et al.[117]
      Microbial inoculant Panax quinquefolium;
      Salvia miltiorrhiza      		 Reduction of heavy-metal uptake;
      regulation of rhizosphere microbial assembly      		 Cao et al.[118];
      Wei et al.[119]
      Nutrient deficiency AMF Glycyrrhiza uralensis Regulation of P and K uptake; improving nutrient utilization Chen et al.[120]
      Bacillus sp. Mentha arvensis Improving P solubilization Prakash and Arora[121]
      Bacillus sp. Camellia sinensis Regulation of K utilization Pramanik et al.[122]
      Serratia sp. Achyranthes aspera Improving P solubilization, IAA level and siderophore production Devi et al.[123]
      Bacterial combination/syncoms Angelica dahurica Regulation of nutrient uptake Jiang et al.[40]
      Astragalus mongolicus Regulation of nutrient uptake; regulation of rhizosphere microbial assembly Shi et al.[124]
      Camellia sinensis Regulating root development;
      Regulation of the N uptake      		 Xin et al.[125]
      Glycyrrhiza uralensis Regulation of nutrient uptake, IAA level and siderophore production Li et al.[126]
      Heat stress Soil suspension Atractylodes lancea Recruiting specific endophytic bacterial Wang et al.[127]
      Chilling stress Fungi and PGPB Ocimum sanctum Regulation of nutrient uptake and the ACCD activity; osmotic regulation Singh et al.[128]
      Flooding stress Bacterial
      combination/syncoms      		 Ocimum sanctum Regulation of the ACCD activity Barnawal et al.[93]

      Table 1. 

      Role of beneficial microorganisms in aiding host plant resisting abiotic stresses.

    • Stress type Strain/microbes Medicinal plant Contribution Ref.
      Drought AMF Glycyrrhiza uralensis
      		 Improving glycyrrhizin and liquiritin production;
      up-regulation of the expression of key genes (e.g. squalene synthase (SQS1), β-amyrin synthase (β-AS)
      and cytochrome P450 monooxygenases (CYP88D6
      and CYP72A154)      		 Orujei et al.[129];
      Xie et al.[63]
      Nicotiana tabacum/ Pelargonium graveolens Enhancement of oil content; up-regulation of the expression of key genes Begum et al.[58]; Amiri et al.[55]
      DSE Glycyrrhiza uralensis Elevation of glycyrrhizin and glycyrrhizic acid content; regulation of the N and P content He et al.[147]
      Bacillus sp. Glycyrrhiza uralensis Enhancement of the total flavonoids, total polysaccharide and glycyrrhizic acid content; up-regulation of the expression of key enzymes (e.g. lipoxygenase and phenylalanine ammonia-lyase); simulation of JA-synthesis Xie et al.[68];
      Yue et al.[76]
      Bacterial combination/ Syncoms Astragalus mongholicus Enhancement of the astragaloside IV and calycosin-7-glucoside content Lin et al.[70]
      Mentha pulegium Improving phenolic, flavonoid and oxygenated monoterpenes production Asghari et al.[73]
      Hyoscyamus niger Improving tropane alkaloid production Ghorbanpour et al.[72]
      Salt AMF Glycyrrhiza glabra Elevation of the glycyrrhizin and terpenoid precursors production Amanifar et al.[148]
      Priestia endophytica Trigonella foenum-graecum Improving phenolic compounds and trigonelline synthesis and N fixation Sharma et al.[86]
      Azotobacter sp. Glycyrrhiza glabra Enhancement of the glycyrrhizic acid and glabridin production Mousavi et al.[91]
      Bacterial combination/ syncoms Artemisia annua Enhancement of the artemisinin production; improving N and P contents Arora et al.[109]
      Foeniculum vulgare Enhancement of the essential oil production Mishra et al.[149]
      Bacopa monnieri Enhancement of the bacoside A production Pankaj et al.[95]
      AM fungi and PGPB Sesamum indicum Improving phenolic, flavonoid, sesamin and sesamolin production Khademian et al.[110]
      Mentha arvensis Enhancement of essential oil content Bharti et al.[150]
      Heavy-metal stress Microbial inoculant Panax quinque folium Enhancement of the ginsenoside production; regulation of the rhizo-microbial structure and composition Cao et al.[118]
      Microbial inoculant Salvia miltiorrhiza Elevation of the total tanshinones content; recruiting beneficial microorganisms Wei et al.[119]
      N-deficiency Bacterial combination Angelica dahurica Enhancement of the furanocoumarin production Jiang et al.[40]
      Astragalus mongolicus Enhancement of the flavonoids, saponins, and polysaccharides contents Shi et al.[124]
      P-deficiency AMF Hypericum perforatum Enhancement of the glycyrrhizic acid, liquiritin, isoliquiritin, and isoliquiritigenin contents; regulation of the nutrient absorption Lazzara et al.[151]
      Polygonum cuspidatum Enhancement of the chrysophanol, emodin, polydatin, and resveratrol contents; regulation of the nutrient absorption Deng et al.[141]
      Nutrient-deficiency AMF Glycyrrhiza uralensis Elevation of the isoliquiritin and isoliquiritigenin content; enhancement of the P, K and microelements absorption Chen et al.[120]
      Heat stress Soil suspension Atractylodes lancea Enhancement of the hinesol, β-eudesmol, atractylon and atractylodin content, up-regulation of the expression of key genes (e.g. 1-deoxy-D-xylulose 5-phosphate synthase (DXS), farnesyl diphosphate synthase (FPPS), 3-hydroxy-3-methylglutaryl-coenzyme (HMGR)); enrichment of specific beneficial bacteria Wang et al.[127]

      Table 2. 

      Role of beneficial microorganisms in the contents of main medicinal compounds in medicinal plants subjecting to abiotic stresses.