Diversity of Streptomyces and Their Plant Growth-Promoting Potential for Sustainable Crop Production.

Biocontrol Potential of Plant Growth Promoting Rhizobacteria against Fusarium oxysporum in Pepper Plants

Aim: This study aimed to examine the biocontrol potential of plant growth-promoting rhizobacteria previously isolated from the tomato rhizosphere against Fusarium oxysporum in pepper plants. Place and Duration of Study: This study was conducted at the Microbiology Laboratory of the Federal University, Oye-Ekiti, between July 2025 and May 2026. Methods: Isolates were obtained from stock cultures and screened for key plant growth-promoting traits, including ammonia, siderophore, nitrogen fixation, and amylase production. Phytopathogenic fungi were isolated from apparently diseased tomato plants. The antifungal activity of the rhizobacterial isolates was evaluated using a dual-culture method. The greenhouse experiment was conducted using a completely randomised block design. Results: Each of the five bacterial isolates exhibited important plant growth-promoting characteristics. Throughout the investigation, isolate IS4A produced the greatest increase in plant height, reaching more than 35 cm by Week 8. By Week 8, isolate IS9 had reached approximately 30 cm, representing the second-highest growth promotion. The highest percentage inhibition of Fusarium was recorded for isolate IS14B (56%), followed by IS13 (47%), IS4A (45%), IS9 (27%), and IS10 (24%). Among all groups, pathogen-inoculated plants (Control 1: Fusarium only) had the lowest fresh weight (5.21 g) and dry weight (0.42 g). IS9 recorded the greatest biomass accumulation, with a fresh weight of 32.12 g and a dry weight of 8.16 g, more than three times the healthy baseline (Control 2: 9.39 g fresh weight and 2.38 g dry weight). Conclusion: The present findings indicate that Pseudomonas lactis and Bacillus tropicus have potential as biological control agents against Fusarium oxysporum while simultaneously promoting pepper growth.

Beneficial microbes isolated from the strawberry rhizosphere: development of growth-promoting and anthracnose-suppressive SynComs

Isolation and Identification of Cyanobacteria and Its Plant Growth Promoting Efficacy using Maize (Zea mays) Seed Germination Experiment

Cyanobacteria are valuable biofertilizers due to their ability to improve nutrient availability and stimulate plant growth. This study investigated cyanobacterial isolates from maize rhizosphere soils collected from 16 maize-growing areas in Central, Oromia, and Southern Ethiopia. Cyanobacteria were isolated from maize rhizosphere soils using BG-11 culture medium and characterized through morphological and biochemical analyses. A total of 132 cyanobacterial isolates were obtained and screened for nitrogen-fixing ability on nitrogen-free BG-11 medium, phosphate-solubilizing activity on Pikovskaya’s agar, and siderophore production using the Chrome Azurol S (CAS) assay.A total Nine isolates showing both nitrogen fixation and phosphate solubilization were further characterized. All selected isolates were positive for catalase and oxidase activities, while eight produced siderophores. The germination promoting effects of cyanobacterial extracts were assessed using a Petri plate germination assay. Among them, isolate Tj~8~ recorded the highest phosphate-solubilization index (2.68). Seed germination experiments on maize varieties BH546 and BH547 revealed significantly higher germination rates in inoculated treatments than in the control. Tj~8~ produced the best individual performance, whereas the consortium Gt~12~ + Tj~8~ achieved the highest germination percentages. These findings suggest that selected cyanobacterial isolates have strong potential for development as eco-friendly biofertilizers for sustainable maize production.

Biocontrol and plant growth-promoting potential of Streptomyces strains against fungal pathogens of tomato and wheat for a sustainable agriculture.

BACKGROUND Modern agriculture urgently requires sustainable alternatives to synthetic chemical pesticides to mitigate crop yield losses while protecting human health and the environment. This study evaluated the biocontrol potential and plant growth-promoting (PGP) traits of three newly isolated Streptomyces strains (Strep_22, Strep_23, and Strep_24) against severe soilborne fungal pathogens affecting durum wheat (Triticum durum Desf.) and tomato (Solanum lycopersicum L.), two economically crucial crops. RESULTS In in vitro dual-culture assays, strain Strep_22, identified as Streptomyces netropsis, demonstrated the highest overall efficacy, achieving a mean fungal growth inhibition rate of 91.52% and near-complete suppression of critical pathogens such as Agroathelia rolfsii, Fusarium solani, and Sclerotinia sclerotiorum. Kinetic modelling confirmed that Strep_22 significantly reduced fungal growth rates. Based on these outstanding findings, Strep_22 was selected for in vivo glasshouse validation. Glasshouse trials demonstrated that treatments with this strain significantly reduced disease incidence and severity (such as root rot and wilt) in both wheat and tomato crops. Concurrently, Strep_22 exhibited strong PGP traits, inducing a significant increase in plant biomass, shoot height, and root development compared to untreated, infected controls. CONCLUSION The Streptomyces strain Strep_22 represents a highly promising, dual-action biocontrol agent. It effectively protects wheat and tomato crops against devastating fungal infections while simultaneously stimulating plant vegetative growth and development. Consequently, it constitutes a valuable ecological alternative for the formulation of commercial biofertilizers and biopesticides, paving the way toward sustainable agricultural systems. © 2026 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Bioprospecting of Plant Growth-Promoting Rhizobacteria for the Management of Late Leaf Spot Disease

The results demonstrate that indigenous PGPR associated with the groundnut rhizosphere possess promising antagonistic activity against N. personata and represent potential candidates for the development of environmentally sustainable management strategies for late leaf spot disease.

Integrating biocontrol efficacy and genomic potential of Bacillus velezensis BJ-1141: from broad-spectrum antagonism to tomato Fusarium wilt suppression.

B. velezensis BJ-1141 is a multifunctional bacterial strain with strong biocontrol efficacy and plant growth-promoting traits, supported by genomic evidence, and represents a promising candidate for sustainable crop disease management.