Figures (1)  Tables (3)

    • Figure 1. 

      Benefits of Serratia species to host-plants.

    • No. Plant growth-promoting traits Mechanisms Serratia species Ref.
      1 Colonization Biofilm formation S. marcescens
      S. plymuthica
      S. fonticola
      S. oryzae
      Serratia spp.      		 [2,36−39,44,46−50,53]
      Chemotaxis
      Entry into root hairs and leaf stomata
      2 IAA production Trp-dependent pathway S. marcescens
      S. liquefaciens,
      S. plymuthica
      S. Rubidaea S. glossinae
      S. nematodiphila
      Serratia spp.      		 [5,8,26,38,48,57−59,90]
      3 Nitrogen conversion Nitrogen fixation S. marcescens
      S. nematodiphila
      Serratia spp.      		 [2,26,58,63,64]
      Denitrification-DNRA-nitrification
      4 Minerial solubilization Organic acid production S. marcescens
      S. nematodiphila
      S. plymuthica
      Serratia spp.      		 [26,44,58,65,67−69,71,74,123]
      H+ extrusion
      Exopolysaccharide production
      Siderophores producion
      Solubilizing enzyme production
      5 Nutrient breakdown Extracellular hydrolytic enzyme
      production      		 S. marcescens
      Serratia spp.      		 [53,64]
      6 Abiotic stress alleviation ACC deaminase production S. marcescens
      S. liquefaciens
      S. proteamaculans
      Serratia spp.      		 [5,6,44,58]
      Induced systemic tolerance
      PGP traits stimulation
      Cadmium (Cd) detoxification
      Pyrene degradation
      7 Induced systemic resistance Elicited by AHLs,
      bacterial flagellin (flg22), translation elongation factor Tu (elf18), and
      2,3-butanediol      		 S. marcescens
      S. liquefaciens
      S. rhizosphaerae
      Serratia spp.      		 [17,39,82,83]

      Table 1. 

      Plant growth promoting traits of Serratia species.

    • No. Compounds produced by
      Serratia spp.      		 Analyzed biosynthetic genes Mechanisms of action Ref.
      1 Protease yfgC Degrading the cell walls of most of fungi and the insect's midgut [8,22,47,48,76,89,90,111]
      2 Chitinase chiA,B, C Degrading the cell walls of most of fungi
      Degrading the insect exoskeletons
      3 β-1,3 glucanase Gene encoding β-1,3-glucanase
      in glycoside hydrolase family      		 Degrading the cell walls of most of fungi
      4 Lipase lipA,B,C,D Degrading the insect's mitgut [140]
      5 Phospholipase phlA Degrading the peritrophic membrane lining the midgut [109]
      6 Serralysin
      (alkaline metalloprotease)      		 prtA1-prtA4 Promoting hemolymph bleeding in insect pests [22,114−116]
      7 Prodigiosin
      Tripyrrole alkaloid      		 pig gene cluster (pig A-N) Inhibiting spore germination and growth of hyphae
      Inhibiting immune system enzymes protease phosphatase, acid phosphatase, and acetylcholine esterase
      Reducing pH in the insect's midgut      		 [7−9,57,91,117−121]
      8 Pyrrolnitrin - tryptophan-derived secondary metabolite prnABCD Damaging the cell membrane in combination with phospholipids
      Inhibiting fungal growth by inhibiting the respiratory electron transport system      		 [8,37,48,90,93−95]
      9 Oocydin A - chlorinated macrocyclic lactone ooc gene cluster Anti-oomycete activity
      		 [4,141]
      10 Biosurfactants
      Serrawettin W1, Serrawettin W2      		 swrW, swrA Swarming activity of Serratia spp.
      Biosurfactant activity disturbing the cell membrane of phytopathogenic cells      		 [21,96,97]
      11 Serratiochelin A, B, C, D
      Bis catecholate siderophores      		 sch gene cluster Iron competition with phytopathogenic cells [48,90,139,142]
      12 Volatile organic compounds (VOCs)
      Sodorifen
      DMDS
      acetic acid, methylthiolacetate
      Terpene synthase gene (Q5A_011535)
      mdeA
      Methyltransferase gene (Q5A_011540)
      		 Inhibition of fungal growth [99−101]

      Table 2. 

      Common compounds produced by Serratia for the control of plant diseases and insect pests.

    • No. Strains Hosts Applications Ref.
      1 S. marcescens IRBG500 Rice (Oryza sativa L.) Improving plant biomass [2]
      2 S. marcescens OK482790 Wheat (Triticum aestivum L.) Improving plant biomass [64]
      3 S. nematodiphila EU-PW75 Barley (Hordeum vulgare L.) Reducing plant abiotic stress
      Improving plant biomass      		 [123]
      4 S. proteamaculans M35 Wheat (Triticum aestivum L.) Reducing plant abiotic stress
      Improving plant biomass      		 [77]
      5 S. plymuthica MBSA-MJ1 Petunia (Petunia × hybrida), impatiens (Impatiens walleriana), and pansy
      (Viola × wittrockiana)      		 Reducing plant abiotic stress
      Improving plant biomass under      		 [124]
      6 Serratia sp. Wed4 Barley (Hordeum vulgare L.) Reducing plant abiotic stress
      Improving plant biomass      		 [58]
      7 Serratia CP-13 Maize (Zea mays L.) Reducing plant abiotic stress
      Improving plant biomass      		 [79]
      8 S. nematodiphila (code SN01) Rice (Oryza sativa L.) Biocontrol of Rice blast caused by
      Magnaporthe oryzae Improving grain yield      		 [127]
      9 S. nematodiphila RGK Turmeric rhizome (Curcuma longa L.) Biocontrol of Pythium aphanidermatum
      Improving plant biomass and bioactive compounds      		 [26]
      10 Serratia liquefaciens, S. plymuthica and S. rubidaea Oilseed rape (Brassica napus L.) Biocontrol of Verticillillm dahliae , Rhizoctonia solani and Sclerntinia sclerotiorum [8]
      11 S.liquefaciens CL80 Dutch white cabbage
      (Brassica oleracea L.)      		 Biocontrol of B. cinerea [125]
      12 S. plymuthica HRO-C48
      		 (Fragaria × ananassa Duch.) Biocontrol of Verticillium dahliae and
      Phytophthora cactorum      		 [47]
      13 Cucumber (Cucumis sativus L.), bean (Phaeseolus vulgaris L.),and tomato (Lycopersicon esculentum L.) Biocontrol of Pythium apahnidermatum and
      Botrytis cinerea      		 [37]
      14 Oilseed rape (Brassica napus L.) Biocontrol of Verticillium wilt [48]
      15 S. nematodiphila CT-78 Rice (Oryza sativa L.) Biocontrol of leaf blight disease [25]
      17 S. marcescens Dolichos bean (Lablab purpureus L.) Biocontrol of Anthracnose disease caused by Colletotrichum lindemuthianum [132]
      18 Serratia sp. G3 Wheat (Triticum aestivum L.) Biocontrol of Botrytis cinerea, Cryphonectria parasitica, Rhizoctonia cerealis and Valsa sordida [90]
      20 S. marcescens NPKC3_2_2 Rice (Oryza sativa L.) Reducing the damages from rice stem borer attacks (Scirpophaga innotata) in rice crops [108]
      21 S. marcescens HJ-01 The red palm weevil (RPW), Rhynchophorus ferrugineus (Olivier) Reducing the red palm weevil (RPW), Rhynchophorus ferrugineus (Olivier) larvae [111]
      22 S. marcescens B2 Rice (Oryza sativa L.) Eliciting plant ISR against rice blast caused by Pyricularia oryzae [85]
      23 S. liquefaciens MG1 Tomato (Lycopersicon esculentum L.) Inducing systemic resistance against Alternaria alternata infection [83]
      24 S. marcescens Tomato (Lycopersicon esculentum L.) Inducing systemic resistance against against root-knot nematode Meloidogyne incognita [126]
      25 S. marcescens 90-166 Tobacco (Nicotiana tabacum L.) Inducing systemic resistance against Pectobacterium carotovorum subsp. carotovorum and Pseudomonas syringae pv. tabaci and cucumber mosaic virus [39]
      26 S. rhizosphaerae KUDC3025 Tobacco (Nicotiana tabacum L.) Inducing systemic resistance against soft-rot disease caused by P. carotovorum subsp. carotovorum SCC1 [17]
      27 S. marcescens GPS5 Groundnut (Arachis hypogaea L.) Inducing systemic resistance against late leaf spot disease [130]
      28 S. marcescens N4-5 (extract) Cucumber (Cucumis sativus L.) Control of cucumber damping-off caused by
      Pythium ultimum      		 [128]
      29 S. marcescens SE1 and SE2 (extracts) Peanut (Arachis hypogaea L.) Control of yellow mold disease caused by A. flavus [129]
      30 S. plymuthica AED38
      (extract)      		 Avocado (Persea americana L.) Control of root rot caused by by Phytophthora cinnamomi [139]
      31 Serratia sp. ARP5.1 (extract) Avocado (Persea americana L.) Control of fruit
      body rot (Colletotrichum gloeosporioides)
      and root rot (Phytophthora Cinnamomi)      		 [138]

      Table 3. 

      Application of Serratia species for enhancing plant growth and plant protection.