RESUMEN
In dry deciduous tropical forests, both seasons (winter and summer) offer habitats that are essential ecologically. How these seasonal changes affect soil properties and microbial communities is not yet fully understood. This study aimed to investigate the influence of seasonal fluctuations on soil characteristics and microbial populations. The soil moisture content dramatically increases in the summer. However, the soil pH only gradually shifts from acidic to slightly neutral. During the summer, electrical conductivity (EC) values range from 0.62 to 1.03 ds m-1, in contrast to their decline in the winter. The levels of soil macronutrients and micronutrients increase during the summer, as does the quantity of soil organic carbon (SOC). A two-way ANOVA analysis reveals limited impacts of seasonal fluctuations and specific geographic locations on the amounts of accessible nitrogen (N) and phosphorus (P). Moreover, dehydrogenase, nitrate reductase, and urease activities rise in the summer, while chitinase, protease, and acid phosphatase activities are more pronounced in the winter. The soil microbes were identified in both seasons through 16S rRNA and ITS (Internal Transcribed Spacer) gene sequencing. Results revealed Proteobacteria and Ascomycota as predominant bacterial and fungal phyla. However, Bacillus, Pseudomonas, and Burkholderia are dominant bacterial genera, and Aspergillus, Alternaria, and Trichoderma are dominant fungal genera in the forest soil samples. Dominant bacterial and fungal genera may play a role in essential ecosystem services such as soil health management and nutrient cycling. In both seasons, clear relationships exist between soil properties, including pH, moisture, iron (Fe), zinc (Zn), and microbial diversity. Enzymatic activities and microbial shift relate positively with soil parameters. This study highlights robust soil-microbial interactions that persist mainly in the top layers of tropical dry deciduous forests in the summer and winter seasons. It provides insights into the responses of soil-microbial communities to seasonal changes, advancing our understanding of ecosystem dynamics and biodiversity preservation.
RESUMEN
Due to its nutritional value and oil, soybean (Glycine max L.) became an economic crop in India and worldwide. The current study investigated the effect of forest-associated plant growth-promoting rhizobacteria (PGPR) on soybean yield and grain nutrient content. Five potential bacteria were used in this study based on their PGPR traits. The pot assay result with two crops (soybean and chickpea) confirmed the growth promotion activity of the two strains (Bacillus subtilis MpS15 and Paraburkholderia sabiae NvS21). The result showed significant (p < 0.05) enhancement in plant length and biomass with the seed treatment with strains (MpS15 and NvS21) compared to the control. Later both biocompatible potential strains were used in field experiments as individuals and consortia. Seed treatment of consortia significantly improves the nodulation and photosynthetic content more than individual treatments and control. Compared to the control, the co-inoculation of MpS15 and NvS21 increased soybean grain, straw yield, and grain NPK contents. Interestingly, soil parameters (organic carbon, available NPK) showed a strong correlation (p < 0.05) with plant parameters and nutrient uptake. Overall, our study provides strong relationships between soil parameters, microbial inoculum as consortia, and soybean performance, and these strains may be utilized as bioinoculant in future.
