Integrative functional profiling of rhizospheric and endophytic bacteria reveals Lelliottia aquatilis as a multifunctional PGPR in Himalayan ecosystems

Endophytic and rhizospheric plant growth-promoting bacterial diversity of Avicennia marina: implications for mangrove sustainability and resilience

Whole-genome sequencing and characterization of Pseudomonas stutzeri P1 endophyte isolated from potato unveils plant growth-promoting and other traits

Endophytic bacteria play an important role in plant growth promotion and stress tolerance, offering sustainable alternatives to chemical inputs in agriculture. In this study, an endophytic bacterial strain P1 was isolated and identified as Pseudomonas stutzeri , a plant-associated bacterium exhibiting multiple plant growth–promoting traits (PGPTs). Biochemical (qualitative and quantitative) and in vitro analyses demonstrated nitrogen fixation, phosphate solubilization, ammonia production, indole-3-acetic acid (IAA) production, biofilm formation, and tolerance to abiotic stresses, including salinity and drought. Furthermore, the P1 strain displayed strong biocontrol activity against the fungal pathogen Fusarium oxysporum f. sp. cumini, indicating its potential to mitigate biotic stress. Whole-genome sequencing generated a high-quality complete genome of 4,758,235 bp. Functional annotation showed enrichment of metabolic pathways associated with plant-microbe interactions and environmental adaptation. Further analyses using KEGG and PGPT-pred data confirmed the presence of genes associated with direct and indirect PGPT, such as nitrogen fixation, phosphate solubilization, biofilm formation, and stress tolerance. The genome also contained genes related to CAZymes, adhesion, and motility, highlighting a strong plant association, whereas the genome lacked major virulence factors and antimicrobial traits, supporting the non-pathogenic nature of the P1 strain. Overall, these findings demonstrate the potential of P1 as a promising bioinoculant candidate for sustainable agriculture in the potato sector.

Multifunctional endophytic bacteria in taro suppress Phytophthora colocasiae and enhance plant growth: a sustainable biocontrol approach

INTEGRATED MORPHOPHYSIOLOGICAL, MOLECULAR, AND FUNCTIONAL CHARACTERIZATION OF MYCOBACTERIUM AGROFLORENSIS REVEALS ITS POTENTIAL AS A SUSTAINABLE AGRICULTURAL BIOINPUT

The development of sustainable agricultural technologies has intensified the search for microbial bioinputs capable of enhancing crop productivity while reducing dependence on synthetic fertilizers. In this context, plant growth-promoting bacteria (PGPB) have emerged as promising biological resources for improving nutrient availability, plant development, and environmental sustainability. This study aimed to perform the morphophysiological, molecular, and functional characterization of the experimental strain Mycobacterium agroflorensis and to evaluate its potential as an agricultural bioinput for sustainable crop production. The strain was cultivated on Middlebrook 7H10 medium and characterized through macroscopic and microscopic analyses, Gram and Ziehl–Neelsen staining, evaluation of growth under different temperatures and pH conditions, 16S rRNA gene sequencing, and phylogenetic analysis. Functional traits associated with plant growth promotion, including phytohormone production, phosphate solubilization, siderophore production, and genes involved in plant–microbe interactions, were investigated. Environmental conditions were monitored using an Internet of Things (IoT)-based platform integrated with environmental sensors. The strain exhibited stable growth on Middlebrook 7H10 medium, producing homogeneous cream-colored colonies with high phenotypic stability. Microscopic analyses confirmed the presence of slender acid-fast bacilli, consistent with the genus Mycobacterium. Optimal bacterial growth was observed at 30°C and pH 7.0, indicating mesophilic behavior and metabolic adaptation to near-neutral conditions. Molecular characterization confirmed the taxonomic identity of the strain, while functional analyses demonstrated traits associated with plant growth promotion. These findings highlight the biotechnological potential of Mycobacterium agroflorensis as a promising microbial bioinput for sustainable agriculture, supporting future studies aimed at field validation and the development of innovative biofertilizers for environmentally responsible crop production.

Isolation and Characterization of Multifunctional Seed-Borne Endophytic Bacterium Lysinibacillus sphaericus YEBEVIA for Enhancing Maize Growth

The endosphere biology attracts increasing interest from researchers seeking to understand plant-microbe synergism and the bio-efficacy of microbial inoculants in enhancing plant growth and soil health. This study was designed to isolate and identify a novel seed-borne endophytic Lysinibacillus sphaericus YEBEVIA with plant growth-promoting capabilities and bioinoculation potential. Morphological assessment revealed that isolate D3 was a Gram-positive, rod-shaped bacterium with a large cell size and undulated colony margins. All the isolates fermented glucose, fructose, sucrose, and maltose, producing only acid from lactose. PGP screening demonstrated that all isolates exhibited beneficial traits, although at varying intensities. Lysinibacillus sphaericus YEBEVIA displayed remarkable zinc-solubilizing ability (3.0 cm), siderophore production (2.5 cm), and high HCN activity (2.87 µg/mL). Phosphate solubilization (17.46 µg/mL) and IAA production (14.26 µg/mL) were also notably high in L. sphaericus YEBEVIA. Heavy-metal tolerance assays revealed that L. sphaericus YEBEVIA responded positively to increasing concentrations of zinc and lead, with the highest growth observed at 2 g supplementation. Enhanced tolerance to chromium was also recorded, whereas cadmium showed no significant effect compared with the control. Minimum inhibitory concentration (MIC) effects were observed only with lead sulphate, producing inhibitory zones of 5.1 cm, 2.5 cm, and 6.8 cm. Bioinoculation studies showed significant improvements in maize growth. Under field conditions, inoculated plants developed 13 leaves, 41 roots, and a fresh weight of 256.9 g, while greenhouse trials produced comparable enhancements. These findings highlight the strong potential of L. sphaericus YEBEVIA as a biofertilizer for sustainable crop improvement.

Wheat native endophytic bacteria isolated from Mediterranean and Atlantic agroecosystems: identification, functional profiling and seedling bioassays

Wheat (Triticum aestivum) cultivation is increasingly challenged by climate change, scarcity of natural resources and dependence on synthetic fertilizers. Plant growth-promoting bacteria (PGPB) represent a promising, sustainable approach to increase crop resilience and enhance resource-use efficiency. However, most studies have primarily focused on PGPB isolated from specific geographical regions and predominantly from the rhizosphere, thereby limiting the exploration of microbial diversity that may harbor novel strains with distinct functional traits and enhanced biostimulant potential. Thus, this study explored wheat-native endophytic bacteria isolated across different agroecosystems in the Mediterranean and Atlantic region, integrating taxonomy, broad multi-trait assessment for functional profiling and seedling bioassays to explore PGPBs with potential for improvement of wheat resilience. A total of 181 isolates belonged to the families Pseudomonadaceae, Bacillaceae and Paenibacillaceae, from which 66 representatives were selected for downstream analysis. Most isolates exhibited relevant plant growth-promoting traits, including indole compounds production (95.5%), 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity (100%), siderophore production (100%), and phosphate solubilization (62%). In addition, many isolates demonstrated tolerance to salinity and PEG-induced osmotic stress. Interestingly, substantial variability was observed among strains in the magnitude of these functional traits. Several isolates significantly enhanced wheat germination and early seedling growth, with Pseudomonas tritici (B254) increasing total biomass by 35.2%. In contrast, Bacillus pumilus (B393) and Pseudomonas sp. (B451) showed inhibitory and suppressive effects on germination and seedling development. These findings reveal a wide range of functional diversity among wheat endophytic bacteria and highlight promising native strains for the development of bioinoculants to improve wheat performance.