Rhizobium Sp Research Articles

Potency of nitrogen fixing bacteria isolated from POME disposal pond and their effect on the growth of Caesalpinia pulcherrima (L) Sw

Nitrogen fixing bacteria (NFB) play an important role to promote plant growth through nitrogen fixation and IAA hormone production. The objective of this research was to obtain the functional bacteria (nitrogen fixing bacteria) isolated from POME disposal pond that show the ability in nitrogen fixation and the potential as plant growth promoting rhizobacteria (PGPR), as well as to investigate the potential of these bacteria through in vitro and in vivo growth of Caesalpinia pulcherrima (L) Sw, and its effect on bacterial populations in media contaminated by POME. In vitro plant growth promoting activity characterization included N-fixing activity, Indole Acetic Acid production, and C. pulcherrima germination (inoculant + POME). In vivo plant growth promoting activity used sterile sand inoculated with NFB and watered with POME, whereas the control was not inoculated and watered with aquadest. Five strains were found as potential PGPR, namely Azotobacter sp., Azospirillum sp1-3., and Rhizobium sp. In addition, Azospirillum sp.1 is the best PGPR that produced highest seed vigour index (SVI), seed germination in vitro, and seed germination in vivo respectively. Azospirillum sp. 1 and Rhizobium sp. have the ability to promote growth of C. pulcherrima in vitro and in vivo with bacterial populations as much as 107cfu mL−1 in POME contaminated media. The bacteria and C. pulcherrima are potential for reclaiming infertile soil.

Theoretical analyses on enantiospecificity of L-2-haloacid dehalogenase (DehL) from Rhizobium sp. RC1 towards 2-chloropropionic acid

Dehalogenases continue to garner interest of the scientific community due to their potential applications in bioremediation of halogen-contaminated environment and in synthesis of various industrially relevant products. Example of such enzymes is DehL, an L-2-haloacid dehalogenase (EC 3.8.1.2) from Rhizobium sp. RC1 that catalyses the specific cleavage of halide ion from L-2-halocarboxylic acids to produce the corresponding D-2-hydroxycarboxylic acids. Recently, the catalytic residues of DehL have been identified and its catalytic mechanism has been fully elucidated. However, the enantiospecificity determinants of the enzyme remain unclear. This information alongside a well-defined catalytic mechanism are required for rational engineering of DehL for substrate enantiospecificity. Therefore, using quantum mechanics/molecular mechanics and molecular mechanics Poisson-Boltzmann surface area calculations, the current study theoretically investigated the molecular basis of DehL enantiospecificity. The study found that R51L mutation cancelled out the dehalogenation activity of DehL towards it natural substrate, L-2-chloropropionate. The M48R mutation, however introduced a new activity towards D-2-chloropropionate, conveying the possibility of inverting the enantiospecificity of DehL from L-to d-enantiomer with a minimum of two simultaneous mutations. The findings presented here will play important role in the rational design of DehL dehalogenase for improving substrate utility.

Remediation of Chromium Contaminated Soil by Phyto-Bio System (PBS) Application

Chromium polluted water was increased as the result of the growth of the industries, due to their industrial waste were most likely contain heavy metals, especially textile industrial waste that was discarded to the rivers. This research aimed to study the removal of chromium levels in soil used the symbiosis between plant and bacteria. Soil sample contained with 4.33 mg kg<sup>-1</sup> and the irrigation water sample contained with 1.09 mg l<sup>-1</sup> of total chromium. This research design was factorial with Randomized Complete Block Design as the based design There were 3 factors in this study: 1. inorganic fertilizer (P): P0: without inorganic fertilizer, P1: with inorganic fertilizer; 2. chelator (B):B0: without chelator, B1: with chelator <em>Rhizobium sp I<sub>3</sub></em>, B2: with chelator manure; 3. Plant (T): T0 without plant, T1: with plant. Data were analyzed by statistical analysis using ANOVA continued by T-test or Duncan Multiple Range test and correlation test. The result showed that the remediation process reduced chromium levels in soil with the removal effectivity up to 71.90% on the treatment combination of NPK fertilizer+manure+plant while removal effectivity on plant-only treatment was 55.66%. The chromium levels in <em>Fimbristylis globulosa</em> were in the range from 1.82–3.15 μ g<sup>-1</sup>, it indicated that <em>Fimbristylis globulosa</em> was a feasible plant for bioremediation. <em>Fimbristylis globulosa</em> grew well and has the ability to absorb chromium, especially by combining it with <em>Rhizobium sp I<sub>3</sub></em>and the chromium uptake in roots was higher than shoots.

Degradation of 3-fluoroanilne by Rhizobium sp. JF-3.

The interest of fluoroanilines in the environment is due to their extensive applications in industry and their low natural biodegradability. A pure bacterial strain capable of degrading 3-fluoroaniline (3-FA) as the sole source of carbon and energy was isolated from a sequencing batch reactor operating for the treatment of 3-FA. The strain (designated as JF-3) was identified by 16S rRNA gene analysis as a member of the genus Rhizobium. When grown in 3-FA medium at concentrations of 100-700mg/L, strain JF-3 almost completely removed 3-FA within 72h. However, the obvious cell growth inhibition was observed in cultures treated with 3-FA concentrations greater than 500mg/L. The degradation kinetics of 3-FA were consistent with Haldane's model with the maximum degradation rate as 67.66mg/(g dry cell h). The growth kinetics of strain JF-3 followed Andrew's model with the maximum growth rate as 30.87h-1. Also, strain JF-3 was able to degrade 4-fluoroaniline, aniline, and catechol, but hardly grew on 2-fluoroaniline, 2,4-dfluoroaniline, 2,3,4-trifluoroaniline, 3-fluorocatechol, and 4-fluorocatechol. Additionally, it was able to grow over a wide pH range (pH 6-10), and also showed tolerance to salinity with lower than 1.0%. This result, in combination with the enzyme assays and analysis of metabolite intermediates, indicated an unconventional pathway for 3-fluoroaniline metabolism that involved conversion to 3-aminophenol and resorcinol by monooxygenase, and which was subsequently metabolized via the ortho-cleavage pathway. To our knowledge, this is the first report on the utilization of 3-FA as a growth substrate by Rhizobium sp.

Characterization of D-Glucoside 3-Dehydrogenase from Rhizobium sp. L35 and Its Application for D-Allose Production

Characterization of D-Glucoside 3-Dehydrogenase from Rhizobium sp. L35 and Its Application for D-Allose Production

Isolation and Characterization of Nodule Endophytes from Bunching and Semi-spreading Groundnut Genotypes

Bacterial endophytes prevalently colonize the internal tissues of plants and are shown to positively influence plant growth. They play a significant role in maximizing crop productivity while reducing the environmental impacts of agriculture. The aim of the present work was to isolate and characterize root nodule endophytes from two groundnut genotypes (Bunching & Semispreading). A total of 20 bacterial isolates were recovered from groundnut nodules using the yeast extract mannitol agar medium supplemented with congo red. The isolates were characterized morphologically, biochemically and compared with the reference strains Rhizobium sp. TNAU 14, Rhizobium sp. COS 1 and Bradyrhizobium sp. The isolates showed close similarity to the reference strains in their biochemical and morphological characteristics. Based on these results, it is concluded that the isolates YBB1, YBB6, YBB8, YBB14A, S27 from the bunching type and YSB 3, YSB4 and YSB5 from the semi-spreading genotype tentatively represent Rhizobium. .

Glucose and arabinose dependent mineral phosphate solubilization and its succinate-mediated catabolite repression in Rhizobium sp. RM and RS

Rhizobium sp. RM and RS are Vigna radiata root nodule isolates with the ability to solubilize tricalcium phosphate and rock phosphate under 50mM Tris-Cl buffering conditions. Rhizobium sp. RM and RS were unique as they could produce two different organic acids, gluconic acid and oxalic acid using glucose and arabinose, respectively, which are two of the most prominent sugars present in the rhizospheric soil. However, P solubilization in these isolates was repressed in the presence of succinate resembling the phenomenon of catabolite repression. RM and RS produced 24mM and 20mM gluconic acid in presence of glucose which was repressed to 10mM and 8mM, respectively, in glucose + succinate conditions. Similarly, RM and RS produced 28mM and 23mM oxalic acid in arabinose containing media which was repressed to 9mM and 8mM, respectively, in the presence of arabinose+succinate. Results of enzyme activities indicated 66% repression of quinoprotein glucose dehydrogenase in glucose + succinate compared to glucose grown cells and 84% repression of glyoxylate oxidase in arabinose+succinate compared to arabinose grown cells. This is perhaps the first report on mechanism of P solubilization in rhizobia through utilization of two different sugars, glucose and arabinose and its repression by succinate. Succinate-mediated catabolite repression of arabinose is the unique aspect of this study.

The mechanistic role of active site residues in non-stereo haloacid dehalogenase E (DehE)

Dehalogenase E (DehE) is a non-stereospecific enzyme produced by the soil bacterium, Rhizobium sp. RC1. Till now, the catalytic mechanism of DehE remains unclear although several literature concerning its structure and function are available. Since DehE is non-stereospecific, the enzyme was hypothesized to follow a ‘direct attack mechanism’ for the catalytic breakdown of a haloacid. For a molecular insight, the DehE modelled structure was docked in silico with the substrate 2-chloropropionic acid (2CP) in the active site. The ideal position of DehE residues that allowed a direct attack mechanism was then assessed via molecular dynamics (MD) simulation. It was revealed that the essential catalytic water was hydrogen bonded to the ‘water-bearer’, Asn114, at a relatively constant distance of ∼2.0 Å after 50 ns. The same water molecule was also closely sited to the catalytic Asp189 at an average distance of ∼2.0 Å, signifying the imperative role of the latter to initiate proton abstraction for water activation. This reaction was crucial to promote a direct attack on the α-carbon of 2CP to eject the halide ion. The water molecule was oriented favourably towards the α-carbon of 2CP at an angle of ∼75°, mirrored by the formation of stable enzyme-substrate orientations throughout the simulation. The data therefore substantiated that the degradation of a haloacid by DehE followed a ‘direct attack mechanism’. Hence, this study offers valuable information into future advancements in the engineering of haloacid dehalogenases with improved activity and selectivity, as well as functionality in solvents other than water.

The effect of sulfur and Rhizobium sp application to the growth and nodulation of Mucuna bracteata

Planting of legumes cover crop, Mucuna bracteata, aims to reduce erosion, increase organic matter, improve soil structure and increase nutrient N. Factors that influence N fixation are food sources, rainfall, sunlight, pH, presence of toxic and competitors. The pH value of the soil is related to the Sulfur element S (sulfur). The study was conducted with 4x4 factorial design with 3 replications. The first factor in the dosage of sulfur consists of S0 (0g), S1 (30g), S2 (60g), S3 (90g) per plant. The second factor is the dose of Rhizobium sp, I0 (0ml), I1 (0.3ml), I2 (0.6ml), I3 (0.9ml), every 1 ml contains 106 cells. Observations were length of tendrils, number of leaves, number of nodules and levels of N. The results of treatment S significantly affected the length of tendrils, number of leaves, number of root nodules, most in S3, 127.50 and soil pH. . Treatment I significantly affected the increase in the number of root nodules, in I3 it increased 86.93%. N levels of all treatments in the high category. The highest N level is 4.17% for S3I2 treatment (90g sulfur and 0.6ml Rhizobium sp).

Diversity and Physiological and Biochemical Properties of Heterotrophic Bacteria Isolated from Lake Baikal Epilithic Biofilms

A total of 170 heterotrophic bacterial strains were isolated from Lake Baikal epilithic biofilms. Identification of the isolates was carried out using the 16S rRNA gene sequencing and physiological and biochemical characteristics. Phylogenetic analysis revealed 59 phylotypes, with three strains probably belonging to new prokaryotic taxa. Members of the cultured biofilm community belonged to 4 phyla and 32 bacterial genera: Proteobacteria (51%), Firmicutes (30%), Actinobacteria (15%), and Bacteroidetes (4%). The genera Aeromonas, Pseudomonas, and Bacillus were predominant. Diversity of the cultured microbial community was higher in the epilithic biofilms than in the water column, neuston, and sponges. Among the isolates, members of ten genera have not been previously found in the Lake Baikal ecosystem: Actinobacteria (Microcella, Pseudoclavibacter, Glaciihabitans, Plantibacter, and Sanguibacter), Proteobacteria (Devosia, Roseomonas, Hydrogenophaga, Iodobacter, and Rhizobium); Glaciihabitans spp. ВА-51-09, ВА-73-09 and Rhizobium sp. ВА-57-09 were new prokaryotic taxa. Statistically significant differences were revealed in the frequency of occurrence of the strains isolated from biofoulings on a steel plate and on natural substrates, as well as on nutrient media with different composition of organic compounds. Most isolates of the genera Aeromonas, Pseudomonas, and Bacillus were capable of degradation of six different polymer substrates, which may indicate their active involvement in organic matter decomposition in biofilms and in Lake Baikal ecosystem in general.

Growth response and N uptake of two soybean varieties on inoculation of Bradyrhizobium sp. in Ultisol Binjai, Sumatera Utara

Ultisol problem is having acidic pH which makes soybean difficult to grow and symbiotic with Brady rhizobium sp. To fixate N. The aim of this research was studied the growth response and N uptake of two soybean varieties on inoculation Brady rhizobium sp. in Ultisol Binjai, Sumatera Utara. This research used Ultisol Binjai with pH 4.5 which was carried out with a pot experiment in the research field of Faculty of Agriculture, Universitas Sumatera Utara, using a Factorial Randomized Block Design with 3 factors. The first factor is Brady rhizobium sp inoculants consisting of without inoculant; BGR3 inoculant; and LP3 inoculant, the second factor is varieties consisting of Anjasmoro and Demas-1. The third factor is liming consisting of without liming and liming with a dose of 7.76 g/10 kg of soil (until pH 5.5). The results of the research showed that application of Brady rhizobium sp inoculant BGR3 was able to increase the N uptake of soybean in Ultisol with an acidic pH which was better than other inoculant. Shoot root ratio tended to increase in Anjasmoro without liming which were application of BGR3 inoculant about 14.15%.

Relative potential of rhizobium species to enhance the growth and yield attributes of cotton (Gossypium hirsutum L.)

Legumes compensate mineral fertilizer by fixing nitrogen due to the specialized structures i.e. nodules by Rhizobium species. Literature revealed that legumes fixed nitrogen due to Rhizobium inoculation from 50-300 kg NPK ha -1 year -1 . Rhizobium besides nitrogen fixation, solubilized phosphates, produced growth hormones and due to its root colonizing ability improved the growth and yield of non-legumes also and performed as plant growth promoting rhizobacteria (PGPR). Study was conducted to assess the relative efficiency of Rhizobium species for the growth and yield of cotton. Different isolates of five species of Rhizobium species responsible for different nodule formation in legumes were assessed for the auxin biosynthesis potential as IAA equivalents and isolates having higher values for IAA equivalents were used for experimentation. Results revealed that isolates of Rhizobium species improved the growth and physiological parameters of cotton. Higher values were root/shoot length and mass were observed with Rhizobium species of berseem (Br 5 ). Bacterial inoculation with isolate (Br 5 ) produced 60.94, 64.40 g shoot/root mass that is 16.70 and 23.80 % higher than control and percent increase improvements of cotton shoot/root length with Br 5 i.e. 18.3, 24.8 % higher than that of control. Higher values of IAA equivalents were observed in root/shoot content of cotton with isolate of Br 5 . Bacterial inoculation improved the plant height, boll weight, number of bolls plant -1 and seed cotton yield with Br 5 inoculation. The chlorophyll content, photosynthetic rate, transpiration rate and photo active radiation were also higher in the inoculated treatments. Results of present study clearly demonstrated that different isolates of Rhizobium species improved the growth and yield parameters of cotton and thus Rhizobium sp can be effectively utilized as bacterial inoculants in non-legumes.

Variovorax sp. Has an Optimum Cell Density to Fully Function as a Plant Growth Promoter.

Utilization of plant growth-promoting bacteria colonizing roots is environmentally friendly technology instead of using chemicals in agriculture, and understanding of the effects of their colonization modes in promoting plant growth is important for sustainable agriculture. We herein screened the six potential plant growth-promoting bacteria isolated from Beta vulgaris L. (Rhizobium sp. HRRK 005, Polaromonas sp. HRRK 103, Variovorax sp. HRRK 170, Mesorhizobium sp. HRRK 190, Streptomyces sp. HRTK 192, and Novosphingobium sp. HRRK 193) using a series of biochemical tests. Among all strains screened, HRRK 170 had the highest potential for plant growth promotion, given its ability to produce plant growth substances and enzymes such as siderophores and 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, respectively, concomitantly with active growth in a wider range of temperatures (10–30 °C) and pH (5.0–10.0). HRRK 170 colonized either as spots or widely on the root surface of all vegetable seedlings tested, but significant growth promotion occurred only in two vegetables (Chinese cabbage and green pepper) within a certain cell density range localized in the plant roots. The results indicate that HRRK 170 could function as a plant growth promoter, but has an optimum cell density for efficient use.

Isotope fractionation in atrazine degradation reveals rate-limiting, energy-dependent transport across the cell membrane of gram-negative rhizobium sp. CX-Z

In the biological mass transfer of organic contaminants like atrazine, the cellular membrane limits bioavailability of pesticides. We aimed to illustrate the roles of cellular membrane physiology and substrate uptake (e.g., passive diffusion and energy-dependent transport) on the limitations of bioavailability in atrazine biodegradation by Gram-negative strain Rhizobium sp. CX-Z. Compound-specific stable isotope analysis revealed energy-dependent transport across cellular membrane led to bioavailability limitations in atrazine biotransformation. Carbon isotope fractionation (ε(C) = −1.8 ± 0.3‰) was observed and significantly smaller in atrazine biodegradation by Rhizobium sp. CX-Z than that expected in acid hydrolysis (ε(C) = −4.8 ± 0.4‰) and hydrolysis by the pure enzyme TrzN (ε(C) = −5.0 ± 0.2‰). However, isotope fractionation was restored in membrane-free cells of Rhizobium sp. CX-Z (ε(C) = −5.4 ± 0.2‰) where no cellular membrane limits substrate uptake. When respiratory chain was inhibited by rotenone, the pseudo-first order kinetic rate constants (0.08 ± 0.03 h−1, 0.09 ± 0.03 h−1) was observed to be statistically less than in the control group (0.23 ± 0.02 h−1, 0.33 ± 0.02 h−1), demonstrating that energy-dependent transport dominated atrazine transfer across the cellular membrane. Therefore, our results revealed energy-dependent transport across cellular membrane existing in Gram-negative strain Rhizobium sp. CX-Z determines bioavailability of atrazine in biotransformation process even at high concentration.

Succinate irrepressible periplasmic glucose dehydrogenase of Rhizobium sp. Td3 and SN1 contributes to its phosphate solubilization ability.

Td3 and SN1 are phosphate-solubilizing nodule rhizobia of Cajanus cajan and Sesbania rostrata, respectively. They solubilized 423µg/mL and 428µg/mL phosphate from tricalcium phosphate through the secretion of 19.2mM and 29.6mM gluconic acid, respectively, when grown in 100mM glucose. However, 90% and 80% reduction in phosphate solubilization coupled to the production of 40mM (Td3) and 28.2mM (SN1) gluconic acid was observed when the two isolates were grown in 50mM succinate + 50mM glucose. Our results illustrate the role of succinate irrepressible glucose dehydrogenase (gcd) in phosphate solubilization and the role of succinate: proton symport in succinate-mediated repression of phosphate solubilization in these rhizobia. Calcium ion supplementation reduced the 88% and 72% repression in P solubilization to 18% and 9% in Td3 and SN1, respectively, coupled to a reduction in media pH from 6.8 to 4.9 in Td3 and 6.3 to 4.8 in SN1. Hence, repression had no genetic basis and is purely due to the biochemical interplay of protons and other cations.

Silicate Solubilization and Plant Growth Promoting Potential of Rhizobium Sp. Isolated from Rice Rhizosphere

Silicon is a beneficial plant nutrient with a vital role in maintaining plant growth and enhancing tolerance to both biotic and abiotic stresses. The polymeric insoluble silica present in soils is solubilised during weathering to release monosilicic acid into the soil solution which is the bioavailable form of silicon absorbed by plants. In the present study, a silicate solubilizing bacterial isolate IIRR-1 from rhizopshere soil of rice was characterized for its potential to release soluble silica from insoluble inorganic (Ca, Al, K and Mg) silicates and biogenic materials like diatomaceous earth, siliceous earth, rice husk and rice straw. Incubation studies revealed the ability of the isolate to colonise and grow on all insoluble silicates leading to increased release of silica (12.45–60.15% over control) into culture media by the process of acidolytic (pH 4.5) dissolution of silicates. The isolate, besides possessing additional mineral (P, K and Zn) solubilising capacities, also exhibited phytostimulatory behaviour by producing IAA (0.95 + 0.14 μg IAA /μg bacterial cell protein) and ACC deaminase activity (2.52 + 0.73 μg α ketobutyrate /μg bacterial cell protein/24 h) that modulates the ethylene levels in plant. Furthermore, the isolate successfully colonized rice seedling roots and improved seedling vigour by 29.18% as compared to uninoculated control. The isolate identified as Rhizobium sp. has the potential to be employed as a plant beneficial bacterium for accelerating the weathering process and increasing the rhizosphere available silica concentration.

Cloning and expression of d-glucoside 3-dehydrogenase from Rhizobium sp. S10 in Escherichia coli and its application for d-gulose production

The novel isolated Rhizobium sp. S10 was identified as d-glucoside 3-dehydrogenase (G3DH) producing microbe. Therefore, the gene encoding for G3DH from Rhizobium sp. S10 was cloned and overexpressed in Escherichia coli strain JM109 as a soluble enzyme complex. The recombinant G3DH (rG3DH) was purified with relatively high specific activity of 38.54 U/mg compared to the previously characterized and cloned G3DHs. The purified rG3DH showed the highest activity at pH 7.0, 40 °C toward cellobiose. It can also oxidize a broad range of mono-disaccharides including saccharide derivatives. The glycosides oxidizing activity combined with chemical reaction, could produce d-gulose from lactitol via 3-ketolactitol.

MICROBIAL POPULATION CHANGES IN THE RHIZOSPHERE OF TOMATO SOLANUM LYCOPERSICUM VARIETIES DURING EARLY GROWTH IN GREENHOUSE

The microbial population changes in the rhizosphere of two varieties of tomato: cherry and plum were studied. They were grown in a greenhouse for five weeks. Standard microbiological procedures were applied. Biochemical and cultural characteristics revealed the presence of Bacillus, Enterococcus, Staphylococcus, Rhizobium as bacterial species and Penicillium, Mucor and Saccharomyces as fungal species. Total Heterotrophic Bacterial Counts (THBC) ranged from 1.0 x 106 to 4.8 x 107 cfu/g; 7.0 x 107 to 4.5 x 109 cfu/g and 5.4 x 107 to 3.0 x 109 cfu/g for bare soil, rhizosphere soil of cherry tomato and rhizosphere soil of plum tomato respectively. Total Fungal Counts (TFC) were lower and ranged from 1.3 x 106 to 6.5 x 106 cfu/g, 1.2 x 106 to 8.7 x 106 cfu/g and 1.0 x 106 to 1.2 x 106 cfu/g for bare soil, rhizosphere soil of cherry tomato and rhizosphere soil of plum tomato respectively. The microbial succession pattern further revealed that Bacillus sp, Enterococcus sp, Rhizobium sp, Mucor sp and Saccharomyces sp were the predominant microorganisms present in bare soil and rhizosphere soils of cherry and plum tomatoes. The presence of plant growth promoting rhizobacteria e.g. Bacillus sp and Rhizobium sp, is of great advantage to the early growth of tomato plants as they play important roles in increasing soil fertility, plant growth , and suppression of phytopathogens for healthy plant development and sustainable agriculture.

Exploration of Root-associated Bacteria from the Medicinal Plant Platycodon grandiflorum.

The present study was performed to investigate root-associated bacteria from Platycodon grandiflorum, a medicinal plant commonly grown in East Asia. Isolates were obtained from the rhizosphere or root interior with various culture media, and phylogenetic analyses were performed based on their 16S rDNA sequences. In consideration of practical applications, traits related to plant growth promotion and niche adaptation were assessed in several endophytic strains with fewer biosafety concerns. The effects of a bacterial inoculation on seedling and mature plant growth were evaluated. Seventeen genera that encompassed more than 30 bacterial lineages were successfully retrieved from the roots, the majority of which have not been reported as P. grandiflorum-associated bacteria, particularly for non-negligible Proteobacteria. Although nitrogen-fixing or phosphate-solubilizing and indole acetic acid-producing activities were recorded in all of the strains selected, these strains were beneficial or detrimental to plant growth as evidenced by their influence on the length of seedlings and biomass of mature plants. Among the 4 endophytic Rhizobium species tested in the present study, the potentially novel Rhizobium sp. BF-E16, which was more compatible with the non-leguminous medicinal plant P. grandiflorum, was identified. Other than plant growth-promoting traits, characteristics such as plant constituent-hydrolyzing activities need to be taken into consideration and their roles clarified when investigating plant growth-promoting rhizobacteria.

Antioxidant and Antifungal Activity of Bacteria Mediated Silver Nanoparticles Using Rhizobium sp

Antioxidant and Antifungal Activity of Bacteria Mediated Silver Nanoparticles Using <i>Rhizobium</i> sp