Effect of Native Soybean Rhizobia and AM Fungi in the Improvement of Nodulation, Growth, Soil Enzymes and Physiological Status of Soybean Under Microcosm Conditions

Abstract

The arbuscular mycorrhizal (AM) fungi-rhizobia synergism is a promising approach for improving the growth and nutrition of soybean. It is, therefore, imperative to evaluate potential soybean rhizobia and AM fungi singly to identify their stress protectant physiological traits, enhance growth and nodulation of soybean and improve soil health. The efficacy of five root nodulating soybean rhizobia and an indigenous AM fungus, Glomus intraradices, was evaluated on soybean (cv JS 93-05) under microcosm conditions. In general, all the inoculated plants showed higher fresh shoot and root weight, and nodule number as compared to uninoculated control plants. The plants inoculated with Bradyrhizobium japonicum (strain USDA 110), B. liaoningense 17c (MTCC 10753) and AM fungus showed higher growth and nodulation. However, the plants inoculated with rhizobia 12c (unidentified), B. japonicum DE2-5a (MTCC 10751) and USDA 205 did enhance nodulation but found at par with the other inoculated plants. Interestingly, these inoculated plants found to have comparatively higher nitrogen and phosphorus uptake. B. japonicum (strain USDA 110), native slow growing rhizobia isolate DE2-5a and AM fungi were also found to stimulate proline content in shoots, and trehalase and fluorescein diacetate activities in the rhizosphere soil. Considering the growth and physiological responses of AM fungi and rhizobial strains (DE2-5a and 17c) to soybean, there is a need for further testing the synergistic responses to evolve better survival candidates under drought-stress conditions.

Impact of Bacterial Dual Inoculation (PSB and Rhizobium) on Nodulation Behavior and Biomass of Sand Culture Grown Kulthi (Dolichos biflorus)

“…Similar observations were also reported by Gupta et al, (2000) and Gupta et al, (2005), Kalita et al, (2006); Garg (2010) and Sharma et al, (2012).They mentioned that the Rhizobium isolate was most effective in respect to increase number of nodules, nodules fresh weight and nodules dry weight in legumes. Saleh et al, (2013) clearly mentioned that Rhizobium inoculation improved nodulation in the varieties of urad bean than that of uninoculated control plant.…”

Comparative conventional and phenomics approaches to assess symbiotic effectiveness of Bradyrhizobia strains in soybean (Glycine max L. Merrill) to drought

“…Increased plant photosynthesis and nitrogen metabolism results in the higher microbial nutritional status of the rhizosphere of soybean inoculated with Rtx strains as revealed by enhanced/improved rhizo-depositions. Microbial inoculations exert very positive roles in improving plant rhizosphere health in arid soils, and similar kinds of increased activity of microbial populations and plant physiological status have been reported in soybean plants inoculated with Bradyrhizobium 23 . The PCA clearly revealed the reliability of the RGB image analysis-based phenomics approach over conventional destructive approaches in assessing symbiotic effectiveness of Bradyrhizobium strain inoculation in soybean under watered (87.41–89.96%) and water-stressed (90.54–94.21%) soil conditions.…”

“…The beneficial effects of Bradyrhizobium spp. on the growth and yield parameters of soybean and other leguminous hosts under irrigated conditions based on conventional approaches are well documented 19 – 23 . However, the understanding and assessment of plant responses to these symbiotic interactions on both plant physiology (plant canopy features, plant water status and photosynthetic efficiency) and biochemical metabolism and their impact due to improved root nodulation and nitrogen fixation through advanced phenomics approaches under low soil moisture stress conditions/moderate drought stress are poor 24 .…”

Priming effect of native rhizosphere bacteria on little millet (Panicum sumatrense)

“…The experiment was carried out in a randomized complete block design with three replications (Sharma et al, 2012).…”