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

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.

Harnessing plant growth promoting rhizobacteria against Fusarium wilt of tomato caused by Fusarium oxysporum f.sp. lycopersici

Abstract Fusarium wilt of tomato, caused by Fusarium oxysporum f. sp. lycopersici, is a major constraint to global production, causing up to 80% yield loss under favourable conditions. Plant growth-promoting rhizobacteria (PGPR) offer an eco-friendly alternative for disease management through growth promotion and pathogen suppression. This study aimed to isolate and characterise PGPR from tomato rhizosphere soils across different agro-climatic zones of Assam and evaluate their antagonistic potential under in vitro and glasshouse conditions. A total of 216 isolates were obtained, of which six showed strong antifungal activity (64–83% inhibition) in dual culture assays. Glasshouse evaluation revealed significant reduction in disease incidence (64.80–80.73%) over control. Molecular identification classified these isolates into Bacillus, Pseudomonas, Clostridium, Lysinibacillus, and Achromobacter. Biochemical analyses confirmed production of indole acetic acid, ammonia, siderophores, and phosphate-solubilizing compounds. These results demonstrate the potential of indigenous PGPR isolates as promising biocontrol agents for suppressing Fusarium wilt of tomato under greenhouse conditions. However, field validation and experiments including pathogen-free PGPR treatments are required to distinguish direct plant growth promotion from disease suppression before practical application.

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

Indigenous rhizospheric Streptomyces possess complementary plant growth-promoting and biocontrol characteristics that support their use as multifunctional bioinoculants.

Rhizospheric Bacteria from Argan and Raspberry Enhance Tomato Resistance to Fusarium oxysporum

Overall, this study demonstrates that multi-trait evaluation, integrating mechanistic screening and in planta validation, provides a more reliable framework for selecting effective biocontrol agents.

Functional diversity and plant growth-promoting activity of endophytic fungi isolated from Thottea siliquosa

Indigenous Putative Nitrogen-Fixing Bacteria from Northern Kazakhstan: Antagonistic Activity and Growth Promotion in Buckwheat

The present study aimed to evaluate the biocontrol and plant growth-promoting potential of putative nitrogen-fixing bacterial strains isolated from the soils of Northern Kazakhstan against major cereal crop phytopathogens and during the early stages of plant development. Phytopathogenic fungi, Fusarium proliferatum and Alternaria alternata, were isolated from infected cereal tissues and seeds using conventional mycological techniques. The antagonistic activity of the bacterial strains was assessed using a dual-culture assay. A total of 26 bacterial isolates were screened for antagonistic activity and plant growth-promoting effects. Several isolates exhibited pronounced inhibitory activity against both pathogens by suppressing fungal mycelial growth. The plant growth-promoting potential of bacterial culture filtrates was evaluated under in vitro conditions using buckwheat (Fagopyrum esculentum Moench) varieties ‘Shortandinskaya 6’ and ‘Shortandinskaya Krupnozernaya’. Germination energy, laboratory germination, shoot length, and root length were recorded during seedling development. The tested bacterial culture filtrates showed a stimulatory effect on seedling growth, with the most pronounced response observed in root elongation, indicating their positive influence on rhizogenesis. The obtained results demonstrate that Agrobacterium pusense st.51S, Ensifer fredii st.59S, and Oricola cellulosilytica st.70S exhibited strong antagonistic activity against Fusarium proliferatum, whereas O. cellulosilytica st.70S, Streptomyces virginiae st.11S, and Ensifer meliloti st.56S effectively inhibited the growth of Alternaria alternata. In addition, E. meliloti st.56S, Priestia megaterium st.35S, Rhizobium giardinii st.2S, and Ensifer sp. st.91S significantly promoted buckwheat seed germination and seedling growth. The most pronounced growth-promoting effect was observed for E. meliloti st.56S, which increased shoot and root length of ‘Shortandinskaya 6’ by 31.4% and 23.8%, respectively, compared with the control. These strains represent promising candidates for the development of microbial bioformulations aimed at improving seed quality, enhancing early plant development, and promoting sustainable crop production under the dry steppe conditions of Northern Kazakhstan.