Rhizobium and Phosphate Solubilizing Bacteria Influence the Soil Nutrient Availability, Growth, Yield, and Quality of Soybean

Abstract

Crop production encounters challenges due to the dearth of nitrogen (N) and phosphorus (P), while excessive use of chemical fertilizers causes environmental hazards. Use of rhizobium and phosphate solubilizing bacteria (PSB) can be a sustainable strategy to overcome these problems. Hence, a pot experiment was conducted following a completely randomized design to explore the impact of nitrogen fixing bacteria and PSB on the growth, yield, and quality attributes of soybean alongside soil nutrient availability using Rhizobium japonicum and Pseudomonas striata. The experiment consisted of two factors—R. japonicum (100% N, R. japonicum alone or with 50% N and control) and P. striata (100% P, only P. striata or with 75% P and control). Results revealed a significant influence of interaction on seed N, yield, protein, oil, and nodules of soybean. Microbial inoculants with or without N and P fertilizers produced a statistically similar yield as 100% N and P. Furthermore, R. japonicum and P. striata along with 50% N and 75% P increased 7% protein and 19% oil than 100% N and P. R. japonicum enhanced soil N content and P. striata improved soil phosphorus availability. Overall, R. japonicum and P. striata inoculation with 50% N and 75% P can potentially improve the yield and the quality of soybean and soil nutrient conditions.

Effects of Co-Inoculating Saccharomyces spp. with Bradyrhizobium japonicum on Atmospheric Nitrogen Fixation in Soybeans (Glycine max (L.))

“…Gaur et al [ 60 ] documented the solubilization of approximately 30–40 kg P 2 O 5 ha −1 due to the inoculation of P-solubilizing microbes. Besides, dual inoculation of beneficial microbes was proven to be more effective than single inoculation considering crop growth and yield because of the augmented effects [ 34 ]. Therefore, based on our experiment’s results, we can postulate that dual inoculation of soybean seeds with an N-fixing bacteria and P-solubilizing yeast leads to improved SDW and RDW.…”

“…In our study, we found that SNP and PNP were significantly higher in soybeans under T5 and T6 when compared to the rest of the treatments ( Figure 4 ). Numerous studies have also found that SNP and PNP are significantly enhanced by dual inoculation of IAA-producing and P-solubilizing microbes [ 34 , 35 ]. This highlights the significance of using more than one microbial isolate as a biofertilizer since these isolates can enhance the effectiveness of each other in P solubilization and IAA production as shown in Figure 1 .…”

“…P also provides enough infection sites for Rhizobium by promoting root and nodule growth [ 21 ]; it assists the N 2 fixing bacteria in building the mitochondrial and symbiosomal membranes of nodules and assimilation of ammonium as amino acids [ 64 ]. Insufficient P encumbers root growth and hampers photosynthesis, as well as the accumulation and translocation of photosynthates and other functions directly related to biological atmospheric N 2 -fixation [ 34 , 63 ]. The scenario of less P and N available or absorbed by the plant, therefore means less plant growth, poor flowering, poor seed set, poor pod filling, and hence low PNP and SNP.…”

“…These PSMs have also been reported to enhance N 2 -fixation, nodulation, root growth, nutrient uptake, and disease tolerance in different plants [ 30 , 31 , 32 , 33 ]. Furthermore, some studies have shown that dual inoculation of these plant growth-promoting microbes improves plant growth relative to the sole inoculation of only one [ 34 , 35 ]. For instance, Shome et al [ 34 ] reported an increase in the growth, yield, and quality of soybean after inoculating the soybean seeds with Rhizobium and P-solubilizing bacteria.…”

“…Furthermore, some studies have shown that dual inoculation of these plant growth-promoting microbes improves plant growth relative to the sole inoculation of only one [ 34 , 35 ]. For instance, Shome et al [ 34 ] reported an increase in the growth, yield, and quality of soybean after inoculating the soybean seeds with Rhizobium and P-solubilizing bacteria. Kumawat et al [ 36 ] also reported that Rhizobium sp.…”