Bioaugmentation, Biostimulation, and Biocontrol in Soil Biology. In: Singh A, Parmar N, Kuhad RC, editors. Bioaugmentation, Biostimulation and Biocontrol. Berlin: Springer Berlin Heidelberg; 2011. pp. 1-23. [DOI: 10.1007/978-3-642-19769-7_1]

Enhancements in morphology, biochemicals, nutrients, and L-Dopa in Faba bean through plant growth promoting rhizobacteria and arbuscular mycorrhizal Fungi

Faba beans are among the main food sources grown since ancient times; seeds contain higher protein (23-41%) than other legumes and are rich in healthy secondary bioactive components. This study was carried out to determine the effects of plant growth-promoting rhizobacteria (PGPR) and arbuscular mycorrhizal fungi (AMF) on the biofortification potential of faba beans. The study utilized Bacillus subtilis, Bacillus megaterium, and an AMF mix to examine changes in growth parameters, chlorophyll content, bioactive compounds, and mineral nutrients. AMF and PGPR treatments significantly enhanced various traits in faba bean pods compared to untreated control plants. Bacillus subtilis treatment increased the antioxidant capacity by 128% and the total phenol content by 230%. AMF inoculation elevated the L-Dopa content, an essential compound for Parkinson's disease prevention, by 92%. Protein content increased by 51% with Bacillus megaterium inoculations. The macro and micronutrients exhibited the highest enhancement in AMF treatment (Ca; 33.6%, K; 49.4%, Mg; 22.7%, P; 10.5%, Fe; 37.7%, Zn; 24.5%). The study results suggest that AMF and PGPR inoculation to faba bean seeds improves the morphological characteristics, bioactive compounds, and mineral nutrient content and is an excellent tool for obtaining biofortified faba beans through sustainable practice.

Characterization of plant-growth-promoting effects and concurrent promotion of heavy metal accumulation in the tissues of the plants grown in the polluted soil by Burkholderia strain LD-11

Plant-growth-promoting (PGP) bacteria especially with the resistance to multiple heavy metals are helpful to phytoremediation. Further development of PGP bacteria is very necessary because of the extreme diversity of plants, soils, and heavy metal pollution. A Burkholderia sp. strain, numbered LD-11, was isolated, which showed resistances to multiple heavy metals and antibiotics. It can produce indole-3-acetic acid, 1-aminocyclopropane-1-carboxylic acid deaminase and siderophores. Inoculation with the LD-11 improved germination of seeds of the investigated vegetable plants in the presence of Cu, promoted elongation of roots and hypocotyledonary axes, enhanced the dry weights of the plants grown in the soils polluted with Cu and/or Pb, and increased activity of the soil urease and the rhizobacteria diversity. Inoculation with the LD-11 significantly enhanced Cu and/or Pb accumulation especially in the roots of the plants grown in the polluted soils. Notably, LD-11 could produce siderophores in the presence of Cu. Conclusively, the PGP effects and concurrent heavy metal accumulation in the plant tissues results from combined effects of the above-mentioned multiple factors. Cu is an important element that represses production of the siderophore by the bacteria. Phytoremediation by synergistic use of the investigated plants and the bacterial strain LD-11 is a phytoextraction process.