TABLE 2.
Microbial biostimulants that mitigate salinity and drought stress in crops.
| Crop Plant | Microbes involved | Mechanism of action | References |
| Protection against salinity stress | |||
| Tomato | Leclercia adecarboxylata MO1 | ACC deaminase and IAA production | Khan et al., 2019 |
| French bean | Aneurinibacillus aneurinilyticus and Paenibacillus sp. | VOCs, ACC deaminase and IAA production | Gupta and Pandey, 2019 |
| Canola | Pseudomonas spp. | ACC deaminase and IAA production | Akhgar et al., 2014 |
| Pepper | Burkholderia and Bacillus | Enhancement of proline accumulation | Ait Barka et al., 2006 |
| Tomato | Pseudomonas fluorescens YsS6 and Pseudomonas migulae 8R6 | IAA production | Ali et al., 2014 |
| Soybean | Pseudomonas simiae | Quinoline and Glycine max 4-nitroguaiacol promote seed germination | Vaishnav et al., 2016 |
| Tomato | Pseudomonas fluorescens UM270 | IAA and VOCs production | Hernández-León et al., 2015 |
| Lettuce | Bacillus subtilis | Cytokinin signaling and shoot biomass | Arkhipova et al., 2007 |
| Potato | Bacillus spp. | IAA production | Tahir et al., 2019 |
| Protection against drought stress | |||
| Wheat | Bacillus thuringiensis AZP2 | Production of volatile organic compounds | Khan et al., 2018 |
| Sunflower | Pseudomonas putida strain GAP-P45 and Pseudomonas spp. PF23 | Production of exopolysaccharide | Tallon et al., 2003; Tewari and Arora, 2014 |
| Pepper | Bacillus licheformis strain K11 | Stress-related protein and genes | Lim and Kim, 2013; Ali and Xie, 2020 |
| Maize | Burkholderia phytofirmans PsJN and Enterobacter sp. FD | Reduced H2O2 induced damage | Naveed et al., 2014 |
| Wheat | Streptomyces coelicolor DE07, Streptomyces olivaceus DE10, and Streptomyces geysiriensis DE27 | Phytohormone (IAA) synthesis and increment in water stress tolerance | Yandigeri et al., 2012 |
| Mung bean | Staphylococcus sp. Acb12, Staphylococcus sp. Acb13 and Staphylococcus sp. Acb14 | Production of indole acetic acid, ACC deaminase, and promotion of plant growth | Jayakumar et al., 2020 |
| Pepper | Bacillus, Achromobacter, Klebsiella sp. and Citrobacter sp. | Production of ACC deaminase | Marasco et al., 2012 |
| Cucumber | Pterolepis glomerata LWL2, Exophiala sp. LHL08, Paecilomyces formosus LHL10, and Penicillium sp. LWL3 | Production of glomalin | Gong et al., 2013; Khan et al., 2015 |
| Beans and carrot | Glomus intraradices | Increasement in the expression aquaporins (GintAQPF2 and GintAQPF1) | Aroca et al., 2008; Li T. et al., 2013 |
| Orange | Funneliformis mosseae | Production of IAA | Liu et al., 2018 |
| Cucumber | Acinetobacter, Pseudomonas, and Burkholderia spp. | Production of gibberellins | Kang et al., 2015 |
| Soybean | Pseudomonas putida H-2-3 | Synthesis of ABA | Kang et al., 2014 |
| Basil | Pseudomonas sp., Bacillus lentus, and Azospirillum brasilense | Production of Ascorbate, peroxidase and glutathione peroxidase | Heidari and Golpayegani, 2012 |
| Wheat | Pseudomonas libanensis EU-LWNA-33 | Adaptive phosphorus solubilization, production of Ammonia, hydrogen cyanide, and ACC deaminase. | Kour et al., 2020c |
| Foxtail millet | Acinetobacter calcoaceticus EU- LRNA-72 and Penicillium sp. EU-FTF-6 | Enhancement of the accumulation glycine betaine, proline, sugars, increased chlorophyll content, and decrease in lipid peroxidation | Kour et al., 2020d |
| Millet | Streptomyces laurentii EU-LWT3-69 and Penicillium sp. strain EU-DSF-10 | Enhancement of the accumulation of glycine betaine, proline, sugars, and decrease in lipid peroxidation | Kour et al., 2020b |