Table 1 Study references for plant growth promoting bacteria used in combination with humic substances
From: Plant growth promoting bacteria and humic substances: crop promotion and mechanisms of action
References | Treatments | Main results |
|---|---|---|
Valero et al. [58] | Humic acid biologically extracted from low-rank coal inoculated with a mixed microbial inoculum of coal solubilizing bacteria (Bacillus mycoides, Acinetobacter baumannii, and Microbacterium sp.) | Edaphic substrate improvements (cation exchange capacity and microbial activity) and increase in the dry weight and the total contents of N and P in the maize seedlings |
Bacilio et al. [61] | Humic acids and Pseudomonas stutzeri were inoculated in chili pepper | Mitigation of salinity effects |
Esringü et al. [62] | Hungarian vetch; three PGPB strains—Agrobacterium rubi strain A1, Bacillus subtilis strain OSU-142 and Bacillus megaterium strain M3; commercial K+-humate | Mitigation of salinity effects |
Schoebitz et al. [53] | Blueberry seedlings: microbial consortium (Bacillus subtilis, B. licheniformis, B. megaterium, B. polymyxa, B. macerans, Pseudomonas fluorescens, P. putida, Nocardia corallina, Saccharomyces cerevisiae and Trichoderma viride). 15 g of humic substances from Leonardite (powder form) was added per seedling | Enhance on plant biomass;—enhance on nutrient uptake (N and K);—changes on the bacteria community at rhizosphere |
Ahmad et al. [57] | Acinetobacter pittii and humic acids | Enhance on crop yield and nutrient efficiency use |
Verma et al. [52] | Cabbage: Pseudomonas fluorescens and humic acid | Nutrient efficiency use; crop yield; plant quality |
Rodrigues et al. [59] | Wheat: Azospirillum brasilense and humic acids | Without results on grain yield |
Befrozfar et al. [55] | Pseudomonas putida, Azospirillum lipoferum, Azotobacter chroococcum and humic acids | Growth promotion |
Winarso et al. [60] | Like humic acids isolated from straw compost and P. putida 27.4B. application directly to the soil and not to the plant | Enhance of P availability in soil; without effect on soybean growth |
Magdi et al. [54] | Bioinoculant with N fixer (Azospirillum and Azotobacter) a P-solubilizer (B. megatherium) bacteria with humic acids applied to cowpea by drip irrigation | Nutrient efficiency use |
Rekha et al. [56] | Pseudomonas putida (estirpe CC-FR2-4) Bacillus subtilis (strain CC-pg104); humic acids | Growth promotion; changes in enzymatic activity |
Young et al. [63] | Bacillus subtilis CCpg104 was attempted with alginate by enriching the bead microenvironment with humic acid | Preservation of cell viability; P solubilization and enhance of root and shoot growth of lettuce plants under gnotobiotic (sterile) condition |