Development of siderophore-based rhizobacterial consortium for the mitigation of biotic and abiotic environmental stresses in tomatoes: Anin vitroandin plantaapproach

Abstract

Aim Tomato‐associated plant‐growth‐promoting rhizosphere bacteria were screened for effective antagonistic activity against the fungal vascular wilt pathogens; tolerance to heavy metals; and enhancing the bioavailability of iron for tomato plants through in vitro and in vivo approaches. Methods and Results Among the 121 rhizobacteria screened for siderophores, 25 isolates were observed to be siderophore producers and out of these, seven isolates chelate copper and iron thus exhibiting in vitro antagonism against the virulent strains of Fusarium oxysporum f. sp. lycopersici MTCC10270 (Fol), Fusarium equiseti MFol and Sarocladium sp. SWL isolated from infected tomatoes. Pseudomonas stutzeri KRP8 was identified to be the most potent strain among the siderophore producers and its siderophores were chemically characterized by mass spectra as metal bound and metal‐free forms. Upon bio‐inoculation of fortified bacterial consortium (siderozote) into the rhizosphere of vermiculite pot cultured tomatoes supplied with varying concentrations of iron and copper ions, we observed in planta growth improvements, antagonism, enhancement of bioavailability of iron and heavy metal tolerance using Inductively Coupled Plasma‐Optical Emission Spectrometry. Conclusion and Significance of the Study Our rhizobacterial consortium provides an opportunity for soil reclamation through an ecofriendly method for a heavy metal‐free agricultural landscape.

Rhizospheric microbiota of suppressive soil protect plants against Fusarium solani infection

“…Kalantari et al 30 used mixtures of Bacillus, Pseudomonas and Rhizobium for root rot control, and the disease index of treated legumes decreased by 62%. Compared with the bacterial consortium of previous studies, 30,[60][61][62] antagonistic fungi such as Trichoderma were used to jointly construct a synthetic consortium, which has higher control potential. At the same time, this study used the keystone microorganisms in suppressive soil that inhibit the growth of pathogens and promote plant growth for the control of root rot, which provided a new idea and theoretical basis for the development of environment-friendly biocontrol agents.…”

Towards further understanding the applications of endophytes: enriched source of bioactive compounds and bio factories for nanoparticles

“…Several microbial species such as Rhodococcus spp, Bacillus spp, Enterobacter spp , Methylobacterium spp, Pseudomonas fluorescens, Pseudomonas putida, Pantoea ananatis and Pantoea agglomerans , etc. are positively shown to produce siderophores ( Karuppiah et al., 2022 ; Singh et al., 2022 ). Endophytes emit different organic acids such as malic, gluconic, and citric acids that convert insoluble soil phosphate (apatite, fluorapatite and hydroxyapatite) into soluble orthophosphates by chelating cations attached to the phosphate ( Fadiji and Babalola, 2020 ), ( Yadav et al., 2018 ).…”

“…Several microbial species such as Rhodococcus spp, Bacillus spp, Enterobacter spp, Methylobacterium spp, Pseudomonas fluorescens, Pseudomonas putida, Pantoea ananatis and Pantoea agglomerans, etc. are positively shown to produce siderophores (Karuppiah et al, 2022;Singh et al, 2022).…”

Enhancing plant growth promoting rhizobacterial activities through consortium exposure: A review

“…Various combinations of PGPR are found in soil that is living symbiotically and performs varieties of efficient, robust activities to maintain the soil and plant health ( Alves et al, 2022 ). The Rhizobacterial consortium also provides protection from biotic and abiotic stress to plants ( Karuppiah et al, 2022 ). A single microorganism cannot provide protection against vast varieties of plant pathogens, that’s why there is an increasing demand for efficient consortium groups to target multiple pathogens that work as dynamic biocontrol agent ( Yaduwanshi et al, 2021 ).…”

“…For the last six years researchers are working on designing rhizobacterial consortium for enhancing plant growth, their yield of production, soil health, as a biocontrol agent, and stabilizing the rhizobacterial interactions ( Kamalnath et al, 2019 ; Swandi et al, 2019 ; Asyiah et al, 2020 ; Kumar et al, 2020 ; Shang and Liu 2020 ; Vaid et al, 2020 ; Redondo-Gómez et al, 2021 ; Karuppiah et al, 2022 ; Shabaan et al, 2022 ) In the current review, the authors have emphasized the role of rhizosphere microbes in PGP activities. Moreover, the authors have also highlighted the recent trends in PGPR-based research works.…”