Jun 2026· Journal of Agriculture and Rural Development Studies· Vol 3, pp. 186-204· 0 citations· 85 references
Abstract
The excessive utilisation of pesticides and chemical fertilizers in modern agriculture generates major problems for the environment, human health and soil quality. In this context, European policymakers, researchers, and farmers are increasingly focusing on alternative solutions that contribute to more sustainable agriculture. Plant growth-promoting rhizobacteria (PGPR) are regarded as biotechnological tools that align well with environmentally friendly alternatives. Numerous PGPR strains are being studied as an ecological alternative to environmentally harmful synthetic preparations (chemical fertilizers, pesticides) and tested for introduction into crop technologies under different formulations, in order to optimize plant growth and improve the production yield. These highly beneficial bacteria colonize on plant roots, stimulating their development through direct and indirect mechanisms. PGPR can improve nutrient availability (nitrogen fixation, phosphorus, potassium, zinc solubilization, etc.) and can influence optimal plant development by producing siderophores and regulating phytohormones. PGPR have the capacity to change the potential for water transport and absorption by roots. Additionally, they can contribute to plant protection by inhibiting pathogens or by stimulating host defence mechanisms, including the production of antibiotics, antioxidants, hydrolytic enzymes, exopolysaccharides, volatile organic compounds (VOCs), and osmotic balancing. The paper provides an overview of the current knowledge regarding PGPR and their importance to enhancing crop productivity and promoting sustainable agricultural practices.
The role of PGPF in climate-resilient cropping systems and circular bioeconomy frameworks, including waste valorization and biofertilizer development is highlighted and key limitations such as host specificity, environmental variability, and scalability challenges are identified.
Kallol Das, A. Sarker, D. Deepo et al.· Phyton· 0 citations
Background: Maize (Zea mays L.) is one of the world's most important cereal crops, and improving its productivity while reducing dependence on chemical fertilizers has become a major goal of sustainable agriculture. The potential role of plant growth promoting rhizobacteria (PGPR) as a biofertilizer evolved as appropriate substitute to neutralize adverse environmental impacts wielded by manmade agrochemical.
Objective: This study aimed to evaluate the effects of Pseudomonas fluorescens and Bacillus subtilis, individually and in combination, on the growth and yield of maize compared with conventional NPK fertilization.
Methods: A field experiment was conducted during the 2025 growing season at the Field Crops Research Station, College of Agriculture, University of Samarra, using a Randomized Complete Block Design (RCBD) with three replicates. Six treatments were evaluated: Untreated control (T1), Pseudomonas fluorescens (T2), Bacillus subtilis (T3), combined inoculation (P. fluorescens + B. subtilis) (T4), combined inoculation with NPK fertilizer (T5), and NPK fertilizer (20:20:20) only (T6). Vegetative growth and yield-related traits were recorded and statistically analyzed.
Results: Inoculation of plants with PGPR bacteria resulted in a significant improvement in both vegetative growth and yield compared to the untreated control group. Pseudomonas fluorescens (T2) exhibited the highest vegetative growth rate, recording the highest plant height (148.00 cm), leaf area (365.00 cm²), leaf area index (2.63), and number of grains per spike (688 grains) compared control group recorded (92.33 cm), (10.67 plant⁻¹), (151.73 cm²), (0.70) respectively. Bacillus subtilis (T3), achieved the highest productivity, producing the largest number of spikes per plant (2.67 spikes) and the highest spike weight (283.50 g) compared control group recorded (2.00) and (161.60 g).
Conclusion: The use of PGPR, and especially Pseudomonas fluorescens and Bacillus subtilis as potential biofertilisation agents is a promising sustainable alternative to chemical fertilisation that can enhance maize growth and production, while decreasing dependence on mineral fertilisers.
Waser saad Khalaf, Ahmed waleed Abdulrahman· International Journal of Bio...· 0 citations
Soil degradation is a major concern, causing a decline in crop productivity and making sustainable agricultural practices essential for humankind. Biochar and plant growth-promoting bacteria (PGPB) are currently applied as affordable and environmentally safe alternatives. Biochar, a porous, carbon-rich by-product of biomass pyrolysis, was applied at 3 % (w/w) alone (control) and in combination with microbial inoculants, including a bacterial consortium. A 15-day pot experiment was conducted under controlled conditions to evaluate the effects of biochar and plant growth-promoting bacteria (PGPB) on plant growth. This study investigates the effects of biochar and PGPB (three Pseudomonas spp. and one Diaphorobacter spp.) on rice (Oryza sativa L.) and mustard (Brassica juncea L.) when applied individually and in combination. The results were evaluated based on plant growth-promoting criteria namely root and shoot length and chlorophyll content. It was observed that biochar had a positive impact on plant growth parameters when applied individually, however in combination with bacterial inoculants, the results were significantly improved. The consortium treatment showed higher values for root length, shoot length and chlorophyll content compared with individual treatments. This study highlights the major scope and potential of utilising plant growth promoting bacteria and biochar to achieve sustainable increases in plant growth and yield. However, some treatments showed variability in results, which could be attributed to the compatibility between biochar and microbial inoculants. This underscores the need for further optimisation studies on the interaction between biochar and bacterial inoculants.
D. Ruchi, S. Sunita, G. Arpita et al.· Plant Science Today· 0 citations
The development of sustainable high-yield farming practices is crucial to support a growing human population while providing long-term solutions for the environmental impact of intensified agriculture. Nutrient-rich bio-residuals generated through the industrial production of insects hold a high but underexplored potential as an alternative to less sustainable fertilizers. In a two-year field experiment, we show that mustard plants grown in insect-exuviae-amended soil perform as well or even better than plants grown in soil amended with reference organic fertilizers. Improved plant performance was driven by increased plant growth in terms of height and width, a larger number of flowers produced, more interactions with pollinators, and a larger seed production compared to untreated plants. A parallel greenhouse experiment revealed that native root-associated microbial communities in exuviae-amended soil were more species-rich, less variable, and were characterized by several well-known plant-growth-promoting rhizobacteria compared to those found in unamended soil or soil treated with reference fertilizer. Collectively, these findings demonstrate that valorizing insect-based bio-residuals can improve agricultural sustainability while simultaneously supporting a circular economy.
Katherine Y. Barragán Fonseca, D. Mertens, Pedro Beschoren da Costa et al.· npj Sustainable Agriculture· 0 citations
The need for the most up-to-date, environmentally friendly techniques of controlling plant diseases and pests necessitates keeping an eye out for effective tools that provide a safe environment for human and animal fitness. In recent years, the usage of plant biostimulants (BS), which are derived from various organic materials through hydrolysis reactions, has increased. Soil microbes and plants immediately absorb these Biostimulants, which often consist of peptides, amino acids, polysaccharides, humic acids and phytohormones with less energy requirement. This benefits not only growth but also the yield and quality of the harvested grain or fruit. These items are intended to promote and increase plant metabolism, reduce stress, etc., rather than to supply nutrients. These days, a variety of biotic and abiotic stresses hinder plant development, seed germination and seedling growth due to shifting climatic conditions, which reduces biological and economic yields. Plant growth regulators (PGRs) helps plant in mitigating different abiotic stresses and also enhances the adaptability of plants in stress conditions. A variety of PGRs, including ethylene (ET), salicylic acid (SA), abscisic acid (ABA) and jasmonates (JAs), are linked to improving plants' ability to respond to various stimuli. On the other hand, under both normal and stressful environmental conditions, PGRs like auxin, cytokinins (CKs), gibberellins (GAs) and relatively novel PGRs like strigolactones (SLs) and brassinosteroids (BRs) are engaged in plant growth and development. These PGRs are crucial for regulating stress adaptation through modulates physiological, biochemical and molecular processes and activation of the defense system, upregulating of transcript levels, transcription factors, metabolism genes, and stress proteins at cellular levels.
Dr. Hena Parveen, Dr. Manish Kumar, Dr. Shweta kumari et al.· Genetics and Molecular Resea...· 0 citations
The increasing demand for sustainable and environmentally responsible agricultural practices has accelerated the search for alternatives to chemical fertilizers. Microbial biofertilizers, particularly plant growth-promoting rhizobacteria (PGPR), offer a promising strategy to enhance crop productivity while maintaining soil health. Among these, Bacillus species have gained significant attention due to their ecological versatility and functional diversity. This review provides a comprehensive evaluation of the biofertilization potential of Bacillus spp. in sustainable agriculture. Prominent species such as Bacillus subtilis, B. megaterium, and B. amyloliquefaciens contribute to improved nutrient acquisition through nitrogen fixation, phosphate solubilization, and potassium mobilization. In addition, Bacillus spp. produce phytohormones, siderophores, and volatile organic compounds that stimulate plant growth and enhance tolerance to biotic and abiotic stresses. Their endospore-forming ability ensures high survival, prolonged shelf life, and reliable performance under diverse field conditions, supporting their commercial application as biofertilizers. This review also discusses interactions between Bacillus spp. and native soil microbiota, their influence on rhizosphere dynamics, and their role in improving soil fertility and crop productivity. However, inconsistent field performance, formulation challenges, and regulatory constraints remain key barriers to large-scale adoption. Recent advances in genomics, strain improvement, and formulation technologies present new opportunities to enhance the efficacy of Bacillus-based biofertilizers. Integrative approaches combining microbiology, agronomy, and policy frameworks are essential to realize their full potential in sustainable agricultural systems and global food security.
Soumendranath Chatterjee, Dibyendu Saha, Souvik Bag et al.· Discover Plants· 0 citations