Effects of co-inoculation ofBradyrhizobium japonicumSAY3-7 andStreptomyces griseoflavusP4 on plant growth, nodulation, nitrogen fixation, nutrient uptake, and yield of soybean in a field condition

Abstract

Co-inoculation of nitrogen-fixing bacteria with plant growth-promoting bacteria has become more popular than single inoculation of rhizobia or plant-growth-promoting bacteria because of the synergy of these bacteria in increasing soybean yield and nitrogen fixation. This study was conducted to investigate the effects of Bradyrhizobium japonicum SAY3-7 and Streptomyces griseoflavus P4 co-inoculation on plant growth, nodulation, nitrogen fixation, nutrient uptake, and seed yield of the 'Yezin-6' soybean cultivar. Nitrogen fixation was measured using the acetylene reduction assay and ureide methods. Uptake of major nutrients [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg)] was also measured. This study showed that single inoculation of SAY3-7 significantly increased shoot biomass; nodulation; Relative Ureide Index (RUI %), percent nitrogen derived from N fixation (% Ndfa); N, P, K, Ca, and Mg uptakes; during the later growth stages (R3.5 and R5.5), compared with control. These observations indicate that SAY3-7 is an effective N-fixing bacterium for the plant growth, nodulation, and nitrogen fixation with an ability to compete with native bradyrhizobia. Coinoculation of SAY3-7 and P4 significantly improved nodule number; nodule dry weight; shoot and root biomass; N fixation; N, P, K, Ca, and Mg uptake; at various growth stages and seed yield in 'Yezin-6' soybean cultivar compared with the control, but not the single inoculation treatments. Significant differences in plant growth, nodulation, N fixation, nutrient uptake, and yield between co-inoculation and control, not between single inoculation and control, suggest that there is a synergetic effect due to co-inoculation of SAY3-7 and P4. Therefore, we conclude that Myanmar Bradyrhizobium strain SAY3-7 and P4 will be useful as effective inoculants in biofertilizer production in the future.

Effects of Biofertilizer Produced from Bradyrhizobium and Streptomyces griseoflavus on Plant Growth, Nodulation, Nitrogen Fixation, Nutrient Uptake, and Seed Yield of Mung Bean, Cowpea, and Soybean

“…The application of the biofertilizer produced from Bradyrhizobium and S. griseoflavus P4 increased the N, P, and K uptakes of soybean and mung bean compared with the control (Tables 7-9). These results support our previous finding that inoculation of Bradyrhizobium with P4 significantly increased the N, P, and K uptakes of soybean compared with an un-inoculated control [48,49]. Beneficial microorganisms can keep the soil environment rich in all kinds of micro-and macronutrients via nitrogen fixation, phosphate and potassium solubilization or mineralization, the release of plant growth regulators, the production of antibiotics, and the biodegradation of organic matter in the soil [18].…”

Influence of Seed Inoculation with Commercial Bacterial Inoculants (Bradyrhizobium Japonicum) on Growth and Yield of Soybean

“…Kozieł et al (2013) and Martyniuk et al (2018) report that a significant increase in the number of pods on the soybean plant is obtained under the influence of inoculation of seeds with symbiotic bacteria. In contrast, Htwe et al (2018) did not show the effect of bacterial inoculants on the number of pods per plant.…”

Legume Biofortification and the Role of Plant Growth-Promoting Bacteria in a Sustainable Agricultural Era

“…Pantoea dispersa MPJ9 and Pseudomonas putida MPJ6 isolates have been tested for their ability to produce siderophores, showing a great Fe chelating potential under Fe deficient conditions; in this study, the Fe content of mung beans was increased 3.4-fold, protein content 2-fold, and carbohydrate content 1.5-fold after inoculation with the strain of P. dispersa [88]. Co-inoculation with Bradyrhizobium japonicum SAY3-7 and Streptomyces griseoflavus P4 improved N, P, K, Ca, and magnesium (Mg) uptake in soybean plants [89]. A recent study showed that seed coating with Zn solution in combination with a Zn solubilizer PGPB, Enterobacter sp.…”

“…Chickpea, Soybean, Wheat Increase Zn uptake [86,90] Acinetobacter tandoii SRI-305, Enterobacter ludwigii SRI-229 Chickpea, Pigeonpea Increase Fe, Zn, Cu, Mn, and Ca uptake [87] Bradyrhizobium japonicum SAY3-7 and Streptomyces griseoflavus P4 Soybean Increase N, P, K, Ca, and Mg uptake [89] Pantoea dispersa MPJ9, Pseudomonas putida MPJ6 Mung bean Increase Fe uptake [88] Bacillus aryabhattai S10 + B. subtilis ZM63 Mung bean Increase N, P, and K uptake [91] Symbion-K (Frauteria aurantia), Pseudomonas sp. RA6, P. citronellis (PC), Serratia sp.…”