Table 1.
Inoculation responses of beneficial rhizobacteria on plant growth.
| Types of biofertilizer | Bacterial strain used | Plant growth promoting activity | Effect on plant productivity parameters | References |
| Nitrogen- fixing bacteria | Azotobacter sp. strain Avi2 (MCC 3432) | Nitrogen fixation, production of IAA, siderophore | improved vegetative and reproductive growth in rice | Banik and Dangar, 2019 |
| Azotobacter chroococcum, A. vinelandii | Nitrogen fixation, P solubilization, production of NH3, HCN, IAA | Increased shoot and root length, leaf and root number, chlorophyll content of maize | Jain et al., 2021 | |
| Herbaspirillum seropedicae (strain ZAE94) | Nitrogen fixation, production of siderophore, IAA | Enhanced mineral uptake, increased diameter, weight, length of ear, number of grains/rows, cob weight and grain yield | Ávila et al., 2020 | |
| Enterobacter cloacae (PGLO9) | Nitrogen fixation, phosphorous solubilization, siderophore production, ACC deaminase | Enhanced potato growth and yield, significant increase in vegetative growth parameters including root and shoot length, root as well as shoot biomass | Verma and Agrawal, 2018 | |
| Bradyrhizobium sp. | Nitrogen fixation, siderophore and IAA production, P solubilisation | Increased vegetative parameters and seed yield in mung bean | Alkurtany et al., 2018 | |
| Rhizobium meliloti | Nitrogen fixation, production of siderophore and chitinase | Increased growth and yield, pods quality and better use of nitrogen in peanut | Mondal et al., 2020 | |
| Phosphate-solubilizing bacteria (PSB) | Pseudomonas stutzeri (CSP03), Bacillus subtilis (TTP02), Pseudomonas putida (PHP03) | Solubilization of P and zinc, IAA, N2 fixation, siderophore, NH3 production | Enhanced plant growth in arid soils | El-Sayed et al., 2014 |
| Alcaligenes faecalis sub sp. faecalis str S8 | P solubilization, production of IAA, hydrogen cyanide, chitinolytic, proteolytic and pectinolytic enzymes | Better growth, increased root weight and length, plant height and aerial plant part weight | Abdallah et al., 2016 | |
| Bacillus subtilis LK14 | P solubilization, production of IAA | Enhanced host plant's nutrient uptake and amelioration of stress | Khan et al., 2016 | |
| R. leguminosarum Pseudomonas moraviensis, Bacillus halotolerans, Enterobacter hormaechei and Pseudomonas frederiksbergensis |
P solubilisation P solubilization, production of IAA, Siderophores, cellulase, ammonia and metal tolerance |
Improved growth and yield, and better resistance against drought in soybean improved wheat seed germination, plant growth, nitrogen and potassium uptake, and Zn absorption | Igiehon et al., 2019; Fahsi et al., 2021 | |
| Potassium-solubilizing bacteria (KSB) | Bacillus edaphicus strain NBT | Potassium solubilisation | Increased root and shoot Growth, and K content in cotton and rape | Sheng, 2005 |
| Bacillus muciloginosus | Potassium solubilisation | Increased the plant biomass, yield and uptake of K in Sudan grass | Basak and Biswas, 2008 | |
| Acidothiobacillus ferooxidans Bacillus cereus | Potassium solubilization Potassium solubilization | Increased growth and yield, improved oil composition in pumpkinIncreased plant height, branches number, shoot dry weight, K uptake and total yield of potato | Ansari et al., 2017; Ali et al., 2021 | |
| Coinoculation of beneficial bacteria | Azotobacter, phosphate solubilising bacteria and potash mobilizing bacteria | Nitrogen fixation, P solubilization, K mobilization, IAA production | Increased yield components and yield of wheat, improved soil nutrients balance, increased microbial activity in the rhizosphere | Game et al., 2020 |
| Azospirillum lipoferum or Azotobacter chroococcum Bacillus megaterium, Arthrobacter chlorophenolicus, Enterobacter sp., Pseudomonas aeruginosa | Nitrogen fixation, IAA production Production of IAA, HCN, siderophore, P-solubilization and N-fixation |
Enhanced growth parameters, pigments, K+, osmolytes, K+/ Na+ ratio and the activity of CAT, POD and APX of the salt-affected maize plants Increased plant height, grain yield, straw yield and nutrients acquisition |
Latef et al., 2020; Kumar et al., 2021 |
IAA: Indole acetic acid; HCN: Hydrogen cyanide; ACC: 1-aminocyclopropane-1-carboxylic acid; PSB: Phosphate solubizing bacteria; KSB: Potassium solubilizing bacteria; CAT: Catalase; POD: Peroxidase; APX: Ascorbate peroxidase.