Rhizobium Biofertilizer Research Articles

Respon penggunaan bakteri penambat nitrogen Rhizobium sp dan pupuk kohe ayam

This study aims to determine the effect of Nitrogen-inhibiting bacteria and chicken manure (cohe) fertilizer on soybean yield. The research method used a 2 factorial Randomized Group Design. The first factor was the treatment of rhizobium biofertilizer (R) consisting of 4 levels, namely R0 = 0 g/kg seed, R1 = 5 g/kg seed, R2 = 10 g/kg seed, and R3 = 15 g/kg seed. The second factor is the treatment of chicken cohe fertilizer (S) consisting of 4 levels, namely S0 = 0 kg/m2, S1 = 0.5 kg/m2, S2 = 1.0 kg/m2, and S3 = 1.5 kg/m2. The results showed that the provision of rhizobium biofertilizer 10 g/kg seed had a real effect on the number of soybean pods, dry weight of seeds per plant, dry weight of 100 seeds, with the highest number of pods 1169.03 g, the highest dry weight of seeds 388.56 g, the highest weight of 100 seeds 15.88 g. Application of chicken cohe fertilizer 1.5 kg/m2 on the soil had a real effect on the number of pods, dry weight of seeds per plant, dry weight of 100 seeds, with the highest number of pods 167.25 g, dry weight of seeds 393.86 g and the highest weight of 100 seeds 16.50 g. The interaction of rhizobium biofertilizer and chicken cohe fertilizer was not significantly different in all treatments.

Improvement of growth and yield of several varieties of soybean following paddy rice using Rhizobium biofertilizer with reduced NPK doses

In paddy fields, soybean is generally planted following harvest of paddy rice crops, and the average yield achieved by farmers is still low. This study aimed to examine the effect of applying Rhizobium biofertilizer with reduced NPK fertilizer dose on growth and yield of soybean grown following flooded rice crop. The experiment, conducted on farmers’ paddy fields in East Lombok (Indonesia) from August to November 2020 was arranged according to Randomized Block Design, with two treatment factors, namely soybean varieties (Anjasmoro, Grobogan, Biosoy-2) and biofertilizers (P0= without biofertilizer, P1= 50% NPK dose + Rhizobium biofertilizer). The results showed that application of Rhizobium biofertilizer did not significantly increase growth and yield of soybean except for weight of 100 grains, but the significant interaction effect on trifoliate number, pod number, unfilled pod number, weight of 100 grains, harvest index, and grain yield indicated that grain yields of Grobogan (2.03 tons/ha) and Biosoy-2 (2.31 tons/ha) were significantly higher with biofertilizer application while that of Anjasmoro variety (2.83 tons/ha) was higher under recommended NPK fertilization doses. It was concluded that the NPK fertilizer dose can be reduced by 50% of the recommended dose if it is accompanied by application of Rhizobium biofertilizer.

Effect of Rhizobium Coating on Physical and Engineering Properties of Chickpea Seed

The Rhizobium bio fertilizer coating may influence on the physical and engineering properties of chickpea seed. The metering mechanism, hopper design and hose pipes of seed drill was designed based up on the physical and engineering properties of Rhizobium coated seeds. The study was conducted to determine the physical and engineering properties viz., length, breadth, thickness, geometric mean diameter, sphericity, seed weight, bulk density, angle of repose and coefficient of static friction of uncoated, and bio-fertilizer coated chickpea seeds for design of Aqu-ferti seed drill. The hopper of seed drill was designed based up on the angle of repose and coefficient of static friction of biofertilizer coated chickpea seeds. The physical properties of chickpea seeds plays very important role in design of hopper, hose pipe and metering mechanism of seed drill The physical properties viz., Length, breadth and thickness of the uncoated and bio-fertilizer coated chickpea seeds were 9.01±0.62 mm, 7.059±0.69 mm, 6.57±0.54 mm and 9.06±0.44 mm, 7.144±0.90 mm, 6.9±0.22 mm, respectively. Roundness and sphericity of uncoated and bio-fertilizers coated chickpea seeds were 87.23 ±2.13%, 87.36±2.72% and 81.6±3.07%, 82±4.15%, respectively. Bulk density of uncoated and bio fertilizer coated seeds were 0.629±0.02 g/cc and 0.641± 0.03 g/cc, respectively. Geometric mean diameters of uncoated and coated seeds were 7.32±0.45 mm and 7.33±.45 mm, respectively. The hopper of seed drill was designed based up on the angle of repose of mild steel which influences on free flow of sesds. The angle of repose for mild steel surface was observed as 26.9±5.61 and 29.51±4.23 degree for uncoated and bio-fertilizer coated chickpea seeds, respectively.

Utilization of Low Cost Biofertilizers for Adsorptive Removal of Congo Red Dye.

Presence of colors, organic surface finishing agents and surfactants in textile industry effluent makes it highly detrimental for surrounding environment. Hence the effluent from textile industry needs treatment for removal of these colors, organic and inorganic components before its disposal. Hence applicability of low cost and environmental friendly biosorbents, Azospirillium biofertilizer and Rhizobium biofertilizer were investigated for removal of Congo red dye. Batch experimentation was carried out to check operating parameters like, temperature, dose of adsorbent, pH, agitation speed, contact time and initial concentration. The biosorption capacity for Congo red dye was 67.114 and 101.01mg/g, for Azospirillium biofertilizer and Rhizobium biofertilizer, respectively at optimized parameters. RL factor was 0.558 and 0.568 for Azospirillium biofertilizer and Rhizobium biofertilizer. The data showed combination of interaction-based separation through better fitting of Langmuir isotherm compared to Freundlich. Its separation is well described by Pseudo-second order and intraparticle diffusion model. Adsorption was favorable at lower temperature suggesting exothermic and spontaneous nature. Reusability for Azospirillium biofertilizer and Rhizobium biofertilizer was checked for 25mg/land. While the biological nature of Azospirillium and Rhizobium biofertilizer makes removal of Congo red dye environmentally benign.

Effect of Rhizobium Inoculation and Phosphate Fertilizer on The Growth of Soybean (Glycine max L) Grobogan Variety

Various strategic efforts to increase food production continue to be made in an effort to achieve self-sufficiency and food security. Soybean is a national strategic commodity to support government programs in an effort to increase production with the aim of achieving self-sufficiency. The purpose of this study was to determine the effect of the combination of phosphate fertilizer and rhizobium biofertilizer on the growth of soybean (Glycine max L) Grobogan variety. The research was conducted from June to September 2022 at the Ma'had Al Zaytun Agricultural Complex, Indramayu Regency. The method used is the method of randomized block design with a combination pattern. There were 9 treatment combinations of SP-36 phosphate fertilizer and rhizobium inoculation. SP-36 Fertilizer consists of 3 levels, namely 100, 150 and 200 kg/ha and Rhizobium with 3 levels, namely 0.05, 0.10 and 0.15 g/planting hole. Each combination was repeated three times so that there were 27 trial plots. Each experimental plot is 6 m2. The observed data were processed using analysis of variance and the Scott-Knott test. The results showed.that the combination-of SP-36 Phosphate fertilizer-and Rhizobium inoculation had-a significant effect on all observations both plant height, number of trifoliate leaves, number of branches, root volume.

Respons kedelai (Glycine max) varietas Mitani terhadap pemberian beberapa jenis pupuk hayati pada tanah podsolik

This study aimed to examine the growth response and yield of Mitani variety soybean plants after treating them with Rhizobium biofertilizer, Phosphate Solvent Microbes, and Azotobacter using gamma-ray irradiation technology. This research was conducted from January to May 2016 and used one-factor Randomized Block Design (RBD) with the several biofertilizer formulas treatments. The treatments level used were K0 = without fertilizer (control); K+ = 100% urea; Rhi = single strain Rhizobium; Rhi+MPF = Rhizobium Inoculant + Phosphate Solvent Microbes; and Rhi+MPF+AZ = Rhizobium + MPF + Azotobacter. Each application of biological fertilizer is mixed with 50% urea fertilizer. The data obtained were analyzed using the F-test (ANOVA) and continued with the Duncan Multiple Range Test (DMRT) at a confidence level α = 0.05. The results showed that the best plant height occurred in soybeans that were given rhizobium fertilizer and pophat solvent microorganisms. Meanwhile, the best average wet and dry weight of soybean plants (p<0.05) occurred in the 100% urea fertilizer treatment. Apart from that, the application of 100% urea fertilizer produces plants with higher water content compared to the biological fertilizer treatment. Another finding from this research is that the number of pods is not directly proportional to the weight of the root nodules. Generaly, it can be concluded that soybean plants respond more to urea fertilization than biological fertilizer.

POTENTIAL OF Rhizobium sp. I 3 AND Agrobacterium sp. I 3 7 IN FORMATION OF ROOT NODULES AND STIMULATING GROWTH OF Arachis hypogaea L.

Rhizobium sp.I 3 and Agrobacterium sp.I 37 bacteria can increase plant growth and have the potential to become a member of the plant growth-promoting rhizobacteria (PGPR). Rhizobium bacteria can increase nitrogen availability for legume plants by forming nodules. Rhizobium sp. and Agrobacterium sp. are closely related; therefore, we speculated that Agrobacterium sp. can also form nodules. The study was based on completely randomized design and conducted from July 2019 to December 2019 in laboratories of the Faculty of Agriculture, Universitas Sebelas Maret, Central Java, Indonesia. The study included 11 different treatments of biofertilizer: P0, P1, P2, P3, P4, P5, P6, P7, P8, P9, P10, and P11 with each treatment in triplicate to obtain 36 experimental units. The results showed that the control treatment (P0) had 0 nodules, 8.26 g biomass, and 3.54% tissue nitrogen uptake. The three best treatments were in the order: P4 ( Rhizobium biofertilizer) with 174.3 root nodules, 14.77% tissue nitrogen (four times higher than that of control), and 24.05 g biomass; P8 ( Rhizobium biofertilizer) with 167 nodules, 12.42% tissue nitrogen (three times higher than that of control), and 19.26 g biomass; P5 ( Agrobacterium biofertilizer) with 146.6 root nodules, 13.15% tissue nitrogen (three times higher than that of control), and 16 g biomass.

Synergetic effects of seaweed extract and Rhizobium on cowpea

Seaweed extracts have been used as fertilizer for crops to enhance yield and quality of the crop products. Only very few studies have been carried out on the effects of seaweed extracts and beneficial soil microbes on growth of crop plants. Hence, the present study was conducted to investigate the synergistic effect of seaweed extract (SE) prepared from Sargassum wightii Greville, with and without the application of Rhizobium biofertilizer, on seed germination, seedling growth, biochemical constituents and yield of cowpea (Vigna unguiculata Walp Var. pusa 151 (family Fabaceae). Seaweed extract (1% concentration), with or without Rhizobium (biofertilizer) treatment, compared with the control, significantly (p≤ 0.05) enhanced vegetative growth (dry weight of shoot and root, number of lateral roots and total leaf area), biochemical parameters (total chlorophyll, carotenoids, proteins, lipids, total sugar and amino acids) and yield and yield components (pod number, length, weight, number of seeds per pod and 100 seeds weight). Seaweed extract application, along with Rhizobium biofertilizer, exhibited better results in terms of vegetative growth, biochemical and yield than the seaweed extract alone in enhancing the growth and yield of a cowpea.

Soybean Cultivation Technology Package on Tidal Swamp Lands in Indonesia

The main constraints of the tidal swamp lands in Indonesia for soybean growth are low soil pH, high Al saturation, and low nutrient availability of N, P, K, Ca, and Mg. The objectives of this research were to determine tolerance of several soybean varieties to Al saturation level, and to obtain a technological package for soybean cultivation which was suitable for farmers to adopt on tidal swamp lands. The research consisted of two stages of study. The first stage formulated of technology package, and the second stage evaluated feasibility of the technology package which was formulation from the first stage. The first stage studied the effect of dolomite application (20%
 - 30% of soil Al saturation) on four soybean varieties (Anjasmoro, Panderman, Dega 1, and Demas). The second stage studied the effect of three technological packages: existing technology; water- saturated soybean cultivation (WSC); and alternative technology which was formulated from the results of the first study. In the 30% of soil Al saturation condition, the alternative technology package (application of 50 kg urea + 75 kg SP36 + 50 kg KCl + 1500 kg organic fertilizers/ha + rhizobium biofertilizer “Agriosy” 0.25 kg/50 g seeds/ha) gave soybean yield of 1.78 - 2.72 t/ha for all
 of soybean varieties tested. The alternative technology package with Anjasmoro variety provided higher seed yields (2.62 t/ha) compared to the existing technology (2.07 t/ha) and WSC technology package (2.44 t/ha). The alternative technology package gave a profit of 11,595,000 IRD/ha with B/C values of 1.71 which was higer than the existing and WSC technology packages. The alternative technology package was more profitable than the existing technology (current farmer practice) and water-saturated soybean cultivation technology packages.

Growth Response of Edamame Soybean (Glycine max (L.) Merr.) with Application of Urea and Rhizobium Biofertilizer on Peat Soil Media

Edamame is a type of soybean that is consumed in an immature period. High demand for market exports especially to Japan, must be balanced by maximizing production with the use of marginal lands. One of marginal lands is peatland which might be used as growth media for edamame with Urea and Rhizobium biofertilizer application to support its growth. The recent study aimed at analyzing the combination of Urea and Rhizobium biofertilizer on the growth of edamame on peat soil media. The experiment was laid out in. Completely Randomized Design (CDR) with two factors. First factor was Urea dosage: p1 = 50 kg ha-1, p2 = 150 kg ha-1, p3 = 100 kg ha-1, p4 = 200 kg ha-1. The second factor was Rhizobium biofertilizer treatment: r0 = without Rhizobium biofertilizer and r1 = Rhizobium biofertilizer 8g kg-1 edamame seeds. All combination was repeated 3 times with 3 polybags of them, so that there were 72 plants in total. The results showed that there was a response between application of Urea and Rhizobium biofertilizer have a significant effect on the observed parameters, that is plant height (cm), number of trifoliate leaves (straind), shoot dry weight (g) and root dry weight (g). The result showed that the application of Urea 50 kg ha-1 with Rhizobium biofertilizer increased plant growth of edamame on peat soil. Keywords: Biofertilizer, Edamame soybean, Fresh vegetable, Wetland

Impact of Rhizobium biofertilizer on agronomical performance of lentil (BARI Masur-6) in Bangladesh

Excessive nitrogen fertilizer uses in crop field causes surface water pollution, which has a harmful effect on the ecosystem. The study was conducted to reducing the use of nitrogen fertilizers during cultivation of pulse crop and as an alternative to increase the use of biofertilizers. Rhizobium can fix atmospheric nitrogen to the soil; it can be used as an alternative to urea for the cultivation of lentil (BARI Masur-6). The Rhizobium leguminosarum was isolated from root nodules of lentil (Lens culinaris) plants and cultured in YEMA (Yeast Extract Mannitol Agar) media. The Rhizobium was screened on the ground of physiological, biochemical and environmental conditions. Different doses of urea fertilizers (20, 40, 60, 80 kg ha-1) and liquid Rhizobium were used in experimental plots. The results indicated that biofertilizer with different chemical fertilizer performed higher than application of several level of urea nitrogen fertilizer in respect of plant height, number, chlorophyll content (µg cm-1) and number of nodules plant-1 with variety BARI Masur-6. There was optimum relative growth rate (RGR) also observed. The increase in urea nitrogen levels was the reason for the decline in relative plant growth. Yield and yield contributing characters like number of pod plant-1, number of seed plant-1, 1000-grain weight (g), grain yield (t ha-1), straw yield and biological yield were significantly influenced by biofertilizer application. The assembled application of biofertilizer and chemical fertilizer produced maximum number of harvest index (%) compare to the chemical fertilizers. Significant correlation found with no of nodule, no of seed, seed weight, grain yield and straw yield. Significant correlation also found in chlorophyll content with some yield contributing characters like seed number, seed weight, grain yield and straw biomass. Further significant correlation observed between pod number and seed number, between seed weight and grain yield. Rhizobium can fulfill the alternate source of nitrogen that promoted significant growth and yield of lentil and it was much closer to the farmer’s conventional amount of urea.

Mulching and nitrogen management in peanut cultivation: an evaluation of productivity, energy trade-off, carbon footprint and profitability

Field study was conducted during winter seasons (November–March) of 2015–2016 and 2016–2017 at the Research Farm of Bidhan Chandra Krishi Viswavidyalaya, West Bengal, India, with an aim to investigate the crop productivity, energy and C budget, carbon footprint and economic sustainability of peanut cultivation fertilized with varied levels of nitrogen under polythene mulching. The experiment laid out in split-plot design comprised of two mulching practices as the main-plot treatments and seven doses of N with or without supplementation of Rhizobium bio-fertilizer as the sub-plot treatments. Fertilization with 100% recommended dose of nitrogen (RDN) + Rhizobium under polythene mulching brought about significant enhancement in pod yield over other nutrient management practices. The effects on yield attributing characters were similar to that of pod yield. Energy indices namely net energy gain, energy productivity, energy intensiveness and energy profitability were the highest with 100% RDN + Rhizobium, irrespective of mulching situations. However, the maximum values of specific energy and nutrient energy ratio were recorded when the crop received 50% RDN with and without Rhizobium, respectively, under mulching and non-mulching situations. Human energy profitability was always greater under mulching situations over non-mulching. Total estimated carbon footprints improved with increase in N level from 0 to 100% RDN with Rhizobium under polythene mulching over non-mulching situations. Highest value of C sustainability index was also observed with polythene covering particularly with the application of 100% RDN + Rhizobium. This treatment combination also proved its superiority with respect to economic benefits in peanut cultivation.

Enhanced nodulation and higher germination using sludge ash as a carrier for biofertilizer production

Sludge ash, a byproduct resulting from the combustion of the dewatered sludge generated in the sewage treatment plants, is recognized as a hazardous solid waste throughout the world. This solid waste, which is produced in behemoth volume, has very limited applications and is directly disposed to landfills. The present study aims to explore a novel strategy for utilizing this solid waste for the development of Rhizobium biofertilizer and thus reducing the burden on landfills. The Rhizobium inoculum was prepared and mixed with sludge ash to formulate Rhizobium biofertilizer, and shelf life of this formulation was evaluated by counting colony forming unit. The prepared formulation was applied on lentil seeds, and its effect was analyzed by assessing the plant growth along with other yield characteristics. Enhanced colony forming unit count (6487.78) was observed in sludge ash carrier combination with a better shelf life of five months in comparison to lignite carrier formulation from the beginning of the experiment (9.1%) till 150th day (69.8%). Lentil seeds treated with sludge ash based biofertilizer showed luxuriant growth with 19% enhanced root length, 42% in number of nodules, 10% in plant growth and 53.40% in seed yield as compared to conventional lignite formulations. Hence, biofertilizer produced from waste material sludge ash is not supposed to cause a hazard for the soil and plants when incorporated in defined amount and can prove to be a substitute for conventional lignite carrier in biofertilizer production.

Alterations in the Endophyte-Enriched Root-Associated Microbiome of Rice Receiving Growth-Promoting Treatments of Urea Fertilizer and Rhizobium Biofertilizer.

We examined the bacterial endophyte-enriched root-associated microbiome within rice (Oryza sativa) 55 days after growth in soil with and without urea fertilizer and/or biofertilization with a growth-promotive bacterial strain (Rhizobium leguminosarum bv. trifolii E11). After treatment to deplete rhizosphere/rhizoplane communities, washed roots were macerated and their endophyte-enriched communities were analyzed by 16S ribosomal DNA 454 amplicon pyrosequencing. This analysis clustered 99,990 valid sequence reads into 1105 operational taxonomic units (OTUs) with 97% sequence identity, 133 of which represented a consolidated core assemblage representing 12.04% of the fully detected OTU richness. Taxonomic affiliations indicated Proteobacteria as the most abundant phylum (especially α- and γ-Proteobacteria classes), followed by Firmicutes, Bacteroidetes, Verrucomicrobia, Actinobacteria, and several other phyla. Dominant genera included Rheinheimera, unclassified Rhodospirillaceae, Pseudomonas, Asticcacaulis, Sphingomonas, and Rhizobium. Several OTUs had close taxonomic affiliation to genera of diazotrophic rhizobacteria, including Rhizobium, unclassified Rhizobiales, Azospirillum, Azoarcus, unclassified Rhizobiaceae, Bradyrhizobium, Azonexus, Mesorhizobium, Devosia, Azovibrio, Azospira, Azomonas, and Azotobacter. The endophyte-enriched microbiome was restructured within roots receiving growth-promoting treatments. Compared to the untreated control, endophyte-enriched communities receiving urea and/or biofertilizer treatments were significantly reduced in OTU richness and relative read abundances. Several unique OTUs were enriched in each of the treatment communities. These alterations in structure of root-associated communities suggest dynamic interactions in the host plant microbiome, some of which may influence the well-documented positive synergistic impact of rhizobial biofertilizer inoculation plus low doses of urea-N fertilizer on growth promotion of rice, considered as one of the world's most important food crops.

Effect of Drought Stress and Bio-fertilizer on Yield and Yield Components of Guar Cyamopsis tetragonoloba (L.) Taub.

The effect of four different levels of irrigation periods, including normal irrigation, irrigation after 100, 150, and 200mm evaporation, with three different bio-fertilizer including control, Mycorrhiza, and Rhizobium were investigated on morphological and yield traits of guar. The experiment was conduct in form of split-plot design with irrigation periods as main plots and bio-fertilizers as sub-plots with three replications in research farm of Sarayan agricultural college-University of Birjand in2016.The results of analysis of variance showed significant effect of investigated irrigation periods on plant height, wilting, root length, pod length, number of pods per plant, grain yield, and biological yield at 1% probability level, and on chlorophyll content, height of the first branch, stem diameter, number of secondary branch, number of seeds per pod, and harvest index at 5% probability level. The interaction effect of drought stress×bio-fertilizers of bio-fertilizers was significant on wilting at 1% probability level and on chlorophyll and pod length at 5% probability level. The results of means comparison analysis revealed that the highest mean of wilting was achieved in severe drought stress induction in control, and application of both Mycorrhiza, and Rhizobium bio-fertilizers. Increasing levels of drought stress led to significant reduction in grain yield and harvest index of guar. Application of Mycorrhiza, and Rhizobium bio-fertilizers did not show significant effect on yield traits of guar under drought stress condition; however the protein percentage of guar’s seeds was increased in moderate drought stress and inoculation with Rhizobium. Based on the results of simple correlation analysis biological yield and harvest index had the highest positive and significant correlation with grain yield of guar and can used as selection criteria under drought stress condition.

Integrated approach to Fertilizer Application on crop productivity and Soil Health in Degraded Jhum Cultivation in Assam

An experiment was conducted to explore the effect of green manure, biofertilizer and inorganic fertilizer on crop productivity and nutrient status in degraded jhum soil. The treatments were made by incorporation of leafy green manure viz., Sesbania bispinosa, Crotalaria pallida, Dalbergia sissoo and Albizia procera, Rhizobium biofertilizer and standard doses of inorganic fertilizer were applied in the plot. Highest amount of crop yield and yield attributes were found in inorganic fertilizer treatment followed by biofertilizer and green manure applied plot at the initial year. Although in successive year green manure (2364.6 kg/h) and biofertilizer (2357.3 kg/h) treatment gave more yield as compared to inorganic fertilizer (1936.5 kg/h) which may be due to input of crop residue. Nutrient uptake of crop was significantly more in green manure and biofertilizer plot compared to inorganic fertilizer applied plot during consecutive year. Soil organic carbon and NPK content was remarkably more in inorganic fertilizer applied plot at the initial year, but in successive year nutrient content was relatively more in biofertilizer followed by green manure and least in inorganic fertilizer applied plot. Observation concludes that application of green manure and biofertilizer in degraded jhum land ensure steady supply of nutrient through decomposition of leafy foliage, improve soil microbe's interaction and thus recuperate soil health that ultimately leads to enhanced crop productivity.

Mining alfalfa (Medicago sativa L.) nodules for salinity tolerant non-rhizobial bacteria to improve growth of alfalfa under salinity stress

There are fewer reports on plant growth promoting (PGP) bacteria living in nodules as helper to tolerance to abiotic stress such as salinity and drought. The study was conducted to isolate rhizobial and non-rhizobial drought and salinity tolerant bacteria from the surface sterilized root nodules of alfalfa, grown in saline soils, and evaluate the effects of effective isolates on plant growth under salt stress. Based on drought and salinity tolerance of bacterial isolates and having multiple PGP traits, two non-rhizobial endophytic isolates and one rhizobial endophytic isolate were selected for further identification and characterization. Based on partial sequences of 16 S rRNA genes, non-rhizobial isolates and rhizobial isolate were closely related to Klebsiella sp., Kosakonia cowanii, and Sinorhizobium meliloti, respectively. None of the two non-rhizobial strains were able to form nodules on alfalfa roots under greenhouse and in vitro conditions. Co-inoculation of alfalfa plant with Klebsiella sp. A36, K. cowanii A37, and rhizobial strain S. meliloti ARh29 had a positive effect on plant growth indices under salinity stress. In addition, the single inoculation of non-rhizobial strains without rhizobial strain resulted in an increase in alfalfa growth indices compared to the plants non-inoculated and the ones inoculated with S. meliloti ARh29 alone under salinity stress, indicating that nodule non-rhizobial strains have PGP potentials and may be a promising way for improving effectiveness of Rhizobium bio-fertilizers in salt-affected soils.

Response of soybean to Rhizobium biofertilizer under different levels of phosphorus

A field experiment was conducted at the Soil Science Field Laboratory of Bangladesh Agricultural University (BAU), Mymensingh during January to May 2015 to study the response of soybean to Bradyrhizobium biofertilizer under different levels of phosphorus on growth, yield, nutrient content and uptake by soybean. The experiment was laid out in a randomize complete block design with three replication of each treatment. The treatments were: To = Control, T1=(100% Nitrogen), T2=(Bradyrhizobium), T3=(Bradyrhizobium inoculation+75% P), T4=(Bradyrhizobium inoculation+10 P), T5=Bradyrhizobium+125% P), T6=(100% RFD+Bradyrhizobium). Potassium and Sulphur at recommended dose were applied as basal to all the treatments. Urea was applied in three spits. Phosphorus in the form of TSP was applied as per treatment during final land preparation. Soybean seeds were inoculated with Bradyrhizobium as per treatments. Intercultural operations were done as and when necessary. Data were collected on pods weight, grain and stover yields. The N and P contents in grain stover and total N and P uptake by soybean were determined. Inoculation of seeds with Bradyrhizobium and application of N and P fertilizer at recommended dose recorded the highest grain and straw yields of soybean. The results suggest that soybean cultivation can effectively be done in the Old Brahmaputra Floodplain soils by Inoculating with Bradyrhizobium biofertilizer in combination with recommended dose of N, P, K and fertilizer.Progressive Agriculture 28 (4): 302-315, 2017

Co-inoculation Effect of Rhizobia and Plant Growth Promoting Rhizobacteria on Common Bean Growth in a Low Phosphorus Soil.

Nitrogen (N) fixation through legume-Rhizobium symbiosis is important for enhancing agricultural productivity and is therefore of great economic interest. Growing evidence indicates that other soil beneficial bacteria can positively affect symbiotic performance of rhizobia. Nodule endophytic plant growth promoting rhizobacteria (PGPR) were isolated from common bean nodules from Nakuru County in Kenya and characterized 16S rDNA partial gene sequencing. The effect of co-inoculation of rhizobium and PGPR, on nodulation and growth of common bean (Phaseolus vulgaris L.) was also investigated using a low phosphorous soil under greenhouse conditions. Gram-positive nodule endophytic PGPR belonging to the genus Bacillus were successfully isolated and characterized. Two PGPR strains (Paenibacillus polymyxa and Bacillus megaterium), two rhizobia strains (IITA-PAU 987 and IITA-PAU 983) and one reference rhizobia strain (CIAT 899) were used in the co-inoculation study. Two common bean varieties were inoculated with Rhizobium strains singly or in a combination with PGPR to evaluate the effect on nodulation and growth parameters. Co-inoculation of IITA-PAU 987 + B. megaterium recorded the highest nodule weight (405.2 mg) compared to IITA-PAU 987 alone (324.8 mg), while CIAT 899 + B. megaterium (401.2 mg) compared to CIAT 899 alone (337.2 mg). CIAT 899 + B. megaterium recorded a significantly higher shoot dry weight (7.23 g) compared to CIAT 899 alone (5.80 g). However, there was no significant difference between CIAT 899 + P. polymyxa and CIAT 899 alone. Combination of IITA-PAU 987 and B. megaterium led to significantly higher shoot dry weight (6.84 g) compared to IITA-PAU 987 alone (5.32 g) but no significant difference was observed when co-inoculated with P. polymyxa. IITA-PAU 983 in combination with P. polymyxa led to significantly higher shoot dry weight (7.15 g) compared to IITA-PAU 983 alone (5.14 g). Plants inoculated with IITA-PAU 987 and B. megaterium received 24.0 % of their nitrogen demand from atmosphere, which showed a 31.1% increase compared to rhizobium alone. Contrast analysis confirmed the difference between the co-inoculation of rhizobia strains and PGPR compared to single rhizobia inoculation on the root dry weight. These results show that co-inoculation of PGPR and Rhizobia has a synergistic effect on bean growth. Use of PGPR may improve effectiveness of Rhizobium biofertilizers for common bean production. Testing of PGPR under field conditions will further elucidate their effectiveness on grain yields of common bean.

Effect of rhizobium biofertilizers on main characteristics and yield of soybean

The aim and tasks of the study. New rhizobium biofertilizers from nodule bacteria will improve nitrogen fixation of soybean. Thus, they will enhance yield capacity, reduce the groundwater leaching of nitrogen and other nutrients in rivers, improving the ecological situation.Materials and methods. Rhizobium biofertilizers GF5 and GF6 and soybean cultivar Heinong 46 were the test material. The experimental variants: application of rhizobium biofertilizers GF5 and GF6, control. Plant height, green plant weight, root nodule number per root, nodule weight were measured in 10 plants at the beginning of flowering, at the peak of flowering and at the seed filling stage for each experimental variant. Soybean seed yield was determined after ripening.Results and discussion. The study found that rhizobium biofertilizer GF6 significantly increased the plant height, green plant weight, nodule number per root, and nodule weight as compared to the control. In particular, the plant height was improved by 1.0% at the beginning of flowering, by 3.0% at the peak of flowering, and by 3.5% at the seed filling phase. The green plant weight was improved by 12.7%, 4.2% and 21.2%, respectively; the nodule number - by 35.4%, 23.7% and 17.6%, respectively; the nodule weight – by 26.3%, 52, 6% and 62.8%, respectively.Rhizobium biofertilizer GF5 did not improved performance at the initial stage of flowering. Some improvement was seen as compared the control at other phases, but it was smaller than that with rhizobium biofertilizer GF6. GF6 also more significantly affected the pod and seed numbers than GF5.Conclusions. Rhizobium biofertilizer GF6 had more significant effects on all the parameters than GF5. Thus, nodules are more competitive, and the efficiency of nitrogen fixation is higher with GF6. This can significantly increase soybean yields.