Effect of Rhizobium, PSB and Mo on the Growth of Different Varieties of Kabuli Chickpea (Cicer kabulinum L.)

The present investigation was conducted with the objective of finding out the Effect of Rhizobium, PSB and Mo on the Growth of Different Varieties of Kabuli Chickpea. The study comprised six treatments of Inoculants I1-Control, I2-Rhizobium(Rh.)+phosphate solubilizing bacteria (PSB) seed inoculation, I3-Molybdenum (Mo)@0.5 g AM* kg-1 seed, I4-Molybdenum @1.0 g AM kg-1 seed, I5-Rh.+PSB+Mo seed treatment @0.5g AM kg-1 seed, I6-Rh.+PSB+Mo seed treatment 1.0g AM kg-1 seed and two varieties V1-RVSJKG 102, V2-Phule G 0517, evaluated in Factorial randomized block design (FRBD) with three replications. The results of the present study revealed that the seed inoculation, I6Rh.+ PSB + Mo@1 g AM kg-1 seed was found to be the best among other inoculants with respect to growth in chickpeas, and Variety Phule G 0517 produced higher values of growth and yield attributing.

Response of Kabuli Chickpea (Cicer kabulinum L.) Varieties to Seed Inoculation with Biofertilizers and Supplementation with Molybdenum

The present investigation was conducted during rabi season 2016-17 at ICARDA, Amlaha farm, Sehore to study the supplementation of Mo along with Rhizobium + PSB inoculation in chickpea cultivars on biological nitrogen fixation and productivity. Research title “Response of Kabuli Chickpea (Cicer kabulinum L.) Varieties to Seed Inoculation with Biofertilizers and Supplementation with Molybdenum”. Six inoculants, with two kabuli chickpea varieties evaluated in Factorial randomized block design (FRBD) with three replications. The results of present study revealed The seed inoculation, I6Rh.+ PSB + Mo@1 g AMkg-1 seed was found best among other inoculants with respect to productivity and profitability in chickpea, and Variety Phule G 0517 produced higher values of growth and yield attributing .

Effect of Plant Growth Regulators and Biofertilizer on the Yield of Fenugreek (Trigonella foenum-graecum L.)

The present investigation entitled “Effect of plant growth regulators and bio fertilizer on growth and quality of fenugreek (Trigonella foenum-graecum L.)” was carried out at the Experimental field, College of Agriculture, RVSKVV, Gwalior during 2020-21 under agro-climatic and soil conditions of Northern Madhya Pradesh. The experiment was laid out in Randomized Block Design (RBD) with three replications. Each replication consists of ten treatments of biofertilizers (viz., Rhizobium, PSB and KSB) and plant growth regulators (viz., GA3 and NAA). All the treatments were randomized separately in each replication. Result showed that the different biofertilizers (i.e. Rhizobium, PSB and KSB) and plant growth regulators (i.e. GA3 and NAA) treatments significantly influenced the yield, yield parameters and economics parameters of fenugreek. Treatment T4 (Rhizobium + NAA) gave the maximum yield, yield parameter and economic parameter it was found best treatment combination as compared to all other treatment combinations of biofertilizers and PGRs, while the minimum yield, yield parameters and economics parameters were recorded in treatment T1 (Control).

Effect of Spacing and Biofertilizers on Growth and Yield of Chickpea

The field experiment was conducted during rabi 2022-23, at Crop Research Farm, Department of Agronomy, SHUATS, Prayagraj (U.P). The soil of the experimental plot was sandy loam in texture, nearly neutral in soil reaction (pH 6.9), low in organic carbon (0.32%), available N (283.93 kg/ha), available P (18.3 kg/ha) and available K (223.5 kg/ha). The experiment was laid out in Randomized Block Design with ten treatments viz. T1: Spacing 20 cm x 15 cm + Uninoculated, T2: Spacing 20 cm x 15 cm + Rhizobium, T3: Spacing 20 cm x 15 cm + PSB, T4: Spacing 30 cm x 10 cm + Uninoculated, T5: Spacing 30 cm x 10 cm + Rhizobium, T6: Spacing 30 cmx 10 cm + PSB, T7: Spacing 40 cm x 10 cm + Uninoculated, T8: Spacing 40 cm x 10 cm + Rhizobium, T9: Spacing 40 cm x 10 cm + PSB and T10: Control: 100% RDF each replicated thrice. The results of the experiment obtained that application of Rhizobium (20 g/kg seeds) along with the Spacing 30cmx10cm significantly increased the growth parameters viz. plant height (46.79 cm), number of nodules (31.93/plant), plant dry weight (22.11 g/plant) and yield parameters viz. number of pods per plant (36.80), seed index (22.15 g), seed yield (3.44 t/ha) and stover yield (4.28 t/ha). This treatment also showed its positive effect on economics viz. gross returns (1,71,834 INR/ha), net returns (1,24,486 INR/ha), B:C (2.63). As the majority of Indian farmers are marginal and poor who cannot afford the use of high cost fertilizers with the result that crops are exposed to nutritional constraints. In such conditions biofertilizers can play an important role in contributing towards soil health and crop productivity. Biofertilizers are a cost effective renewable energy source that plays a crucial role in reducing inorganic fertilizer application and at the same increasing crop yield besides maintaining soil fertility. The optimum spacing for any crop means maintaining uniform and healthy crop stand so as to get optimum yield of crop. The growth and yield of crop is closely related to number of plants per unit area.

Effect of Vermicompost, Biofertilizers and in Organic Fertilizers on Nutrient Uptake and Physico-chemical Properties of Soil: A Case Study of Chickpea (Cicer arietinum L.)

A field trial was conducted during Rabi 2020-21 in randomized block design with three replications and seven treatments comprising individual and combined application of various organic and inorganic nutrient sources at Research Farm, MMU Sadopur (Ambala), Haryana. The experiment was intended to evaluate the effect of vermicompost, biofertilizers and inorganic fertilizers applied in chickpea on nutrient uptake and physico-chemical properties of soil pH (8.24). The highest organic carbon (0.58%), electrical conductivity (0.51 dS m-1), particle density (2.50 g/cm3) and porosity (48.47%) along with maximum available N (126.5 kg ha-1), P (23.2 kg/ha) and K (98.33 kg/ha) were observed in the treatment of T6 i.e., 3 t/ha Vermicompost + Rhizobium + PSB. Similarly, the nutrient content (N, P and K) was maximum in seed and stover of chickpea harvested from the plots receiving 3 t/ha Vermicompost + Rhizobium + PSB, which was statistically at par with T7 i.e., 2.5 t/ha Vermicompost + Rhizobium + PSB. The highest net return was recorded in plots treated with 50% RDF (Recommended dose of fertilizer) + Rhizobium + PSB and 75% RDF + Rhizobium + PSB with a benefit cost ratio (B: C) of 3.2 and 3.1, respectively. However, the seed yield in integrated nutrient management was comparable to recommended dose of chemical fertilizers

The Effect of Integrated Nutrient Management on Various Growth Parameters of Cluster Bean (Cyamopsis tetragonoloba L.)

The present investigation entitled “The effect of integrated nutrient management on various growth parameters of cluster bean (Cyamopsis tetragonoloba L.)” was carried out at Horticultural Research Centre of Sardar Vallabhbhai Patel University of Agriculture & Technology, Meerut – 250110 during 2022-23. In this study integrated nutrient management (INM), farmyard manure (FYM), vermicompost and phosphate solubilizing bacteria (PSB) were used with different combinations. The entitled experiment was conducted in Randomized Block Design (RBD) with three replications. Application of INM dose @ 75% RDF + Vermicompost (1.5 t ha-1) + Rhizobium (2 kg ha-1) + PSB (1 kg ha-1) was found to be the most effective in terms of growth parameters viz., plant height (89.90 cm), number of branches plant-1(9.73), number of clusters plant-1(27.83) and number of leaves plant-1(37.98). Therefore, it can be suggested that a dose of 75% RDF + Vermicompost (1.5 t ha-1) + Rhizobium (2kg ha-1) + PSB (1 kg ha-1) suitable for the commercial cultivation of vegetable cluster bean in the Western Plane Zone of Uttar Pradesh.

Role of Biofertilizers in Chickpea: A Review

Compared to when both rhizobium and the bacteria that solubilize phosphate are inoculated separately, the interaction effect between the two inoculations gradually increases the growth parameters and yield production. Rhizobium and phosphate solubilizing bacteria (PSB) had shown advantage in enhancing chickpea productivity, cost effective, ecofriendly and renewable sources of plant nutrients. Biofertilizers have the ability to improve the growth and nodulation of chickpea enables it to withstand the periods of drought. Utilising Rhizobium's symbiotic properties to increase the nitrogen supply to agricultural plants.

Influence of Integrated Nutrient Management on the Productivity of kharif Redgram (Cajanus cajan L.)

A field experiment was conducted during kharif season of 2021-22 at Agricultural Research Station, Tandur, Vikarabad, Professor Jayashankar Telangana State Agricultural University (PJTSAU) under deep black soils to study the effect of integrated nutrient management on the growth and yield of kharif redgram (Cajanus cajan L.). The experiment was laid out in Randomized block design with 9 treatments in 3 replications. Treatments comprised of T1: Control, T2: 50% RDF (10:25:0 NPK kg ha-1) + 50% FYM (2.5 t ha-1), T3: 75% RDF (15:37.5:0 NPK kg ha-1) + 25% FYM (1.25 t ha-1), T4: 100% RDF (20:50:0 NPK kg ha-1), T5: 50% RDF + FYM @ 5 t ha-1 + Rhizobium (Seed treatment) + PSB (Seed treatment), T6: 75% RDF + FYM @ 5 t ha-1 + Rhizobium (Seed treatment) + PSB (Seed treatment), T7: 100% RDF + FYM @ 5 t ha-1 + Rhizobium (Seed treatment) + PSB (Seed treatment), T8: 100% RDF + Rhizobium (Seed treatment) + PSB (Seed treatment) and T9: FYM @ 5 t ha-1 + Rhizobium (Seed treatment) + PSB (Seed treatment). Among the treatments, application of 100% RDF, FYM @ 5 t ha-1, Rhizobium and PSB recorded significantly higher seed yield (1898 kg ha-1) and stalk yield (6275 kg ha-1).

Effect of Seed Treatment with Bioinoculants on Seed Yield and Quality Parameters in Chickpea (Cicer arietinum L.)

The field experiment, was conducted during Rabi 2022 at the field experimental center, Department of Genetics and Plant Breeding, SHUATS, Prayagraj, (U.P). The soil of the experimental plot was sandy loam in texture, nearly neutral in soil reaction (pH 7.1), low in organic carbon (0.36%), available N (171.48 kg/ha), available P (15.2 kg/ha) and available K (232.5 kg/ha). The experiment was laid out in Randomized Block Design with thirteen treatments including control which were replicated thrice. The treatments are as follows, T0- Control, T1 - Bacillus subtilis – 20 g/kg seeds, T2 – Rhizobium – 20 g/kg seeds, T3 – P.S.B – 20 g/kg seed, T4 - T. harzianum – 20 g/kg seed, T5 - T. viridae – 20 g/kg seed, T6 – B. subtilis + Rhizobium – (10 g + 10 g/kg seed), T7 - Rhizobium + P.S.B – (10 g + 10 g/kg seed), T8 - P.S.B + T. harzianum – (10 g + 10 g/kg seed), T9 – T. harzianum + T. viridae – (10 g + 10 g/kg seed), T10 - T. viridae + B. subtilis – (10 g + 10 g/kg seed), T11 - B. subtilis + Rhizobium + P.S.B – (10 g + 10 g+10 g/kg seed), T12 - P.S.B + T. harzianum + T, viridae – (10 g + 10 g+10 g/kg seed) respectively. The experiment results revealed that seeds treated with T7 – Rhizobium + P.S.B – 10 g + 10 g gave better than other treatments viz, days for 50% flowering (60.00), Days to 50% pod setting (75.00) and has matured earlier (99.00), Plant height (74.90 cm), number of pods per plant (52.33), number of seeds per pod (3.00), Seed yield per plot (522.80 g), Biological yield per plot (613.58), Seed index (32.24 gm). Were recorded significantly higher compared to other treatments.

Integrated Nutrient Management in Green Gram (Vigna radiata L.) for Enhancing Soil Health

Integrated nutrient management (INM) is a holistic approach that involves the application of organic and inorganic fertilizers to improve soil health and crop productivity. The research study was conducted to demonstrate the effective use of INM on soil health in Green gram. We used a randomized block design (RBD) with four levels of poultry manure @ 0, 50, 75 and 100% ha-1, four levels of nitrogen, phosphorous and potassium@ 0, 50, 75 and 100% ha-1 and rhizobium seed treatment. The revealed that treatment T9 (N20P40K40 kg ha-1 + PM @ 5 t ha-1 and Rhi @ 200g 10 kg-1 Seed) resulted in a slight change in soil pH 6.82, electrical conductivity (EC) 0.198 dS m-1. In post-harvest soil of fertilizers observations showed significant increase in pore space 49.20 %, water holding capacity 47.59 %, organic carbon 0.49 %, and available N 334.23 kg ha-1, P 34.58 kg ha-1, K 202.83 kg ha-1. The increase in NPK was found to be significant (P<0.05) among other treatments in Green gram cultivation and soil quality improvement. The application of N P K with poultry manure was a magnificent source of fertilization.

Growth and Yield Response of Cluster Bean (Cyamopsis tetragonoloba L.) cv. Pusa Navbahar to Integrated Nutrient Management

The investigation on cluster bean with application of integrated nutrient management with comprised of 12 treatments with three level of NPK, two levels of PSB and Rhizobium in factorial randomized block design. The treatment T12 has shown the significant results when applied 100% of NPK with PSB and Rhizobium among the different levels of treatment combinations. Growth parameters viz., plant height (90.96 cm), number of nodules plant-1(59.48), number of branches plant-1 (2.66) at 90 DAS (day after sowing), and yield parameters viz., number of clusters plant-1 (14.62), number of pods cluster-1 (13.39), pod length (17.42 cm),pod yield(77.29 q ha-1) has shown best in treatment T12(NPK @100% + PSB @100% + Rhizobium @100%) of cluster bean (Cyamopsis tetragonoloba L.) in comparison to other treatment combination.

Identification and characterization of native rhizobia from three mungbean varieties

Aims@#Native rhizobia from root nodules of mungbean could reduce atmospheric nitrogen to ammonia for assimilation. The objective of this study was to find the best native rhizobium from mungbean. @*Methodology and results@#Three rhizobia isolates from three mungbean varieties (Maejo 3, Khampangsan 2 and Chainat 72) were collected from 10 undamaged fresh nodules at Prince Chakrabandh Pensiri Center for Plant Development, Saraburi Province, Thailand in 2016. 16S rDNA analysis identified the three rhizobia isolates as Bradyrhizobium sp. (SB1), Bradyrhizobium elkanii (SB2) and Rhizobium sp. (SB3). All the isolates could grow well in yeast mannitol agar (YMA) at pH 7, and all isolates could tolerate up to 35 °C, with isolate SB3 tolerate up to 45 °C. Isolate SB2 produced the highest amount of indole acetic acid (IAA; 8.37 mg/L) and had the highest phosphate solubilization index (7.60 SI). In a Leonard jar trial, inoculation with isolate SB2 resulted in the highest shoot fresh and dry biomass of mungbean host. Further, the mungbean inoculated with SB2 had the highest number of root nodules, nodule fresh dry weight, chlorophyll content index, and shoot and root nitrogen contents. @*Conclusion, significance and impact of study@#This study suggested that the strain SB2 (B. elkanii) is a suitable bioinoculant to improve mungbean growth and yield.

Seed size influences the promoting activity of rhizobia on plant growth, nodulation and N fixation in lima bean / O tamanho da semente influencia a atividade promotora dos rizóbios sobre o crescimento de plantas, nodulação e fixação de N em feijão-fava

ABSTRACT: This study evaluated the activity of rhizobia isolates inoculated in large (18 mm) and small (11 mm) seeds on lima bean growth, nodulation and N fixation. Selected rhizobia isolates were compared with a reference strain CIAT899 and two controls without inoculation. Large seeds contributed for highest plant growth, nodulation and N fixation than small seeds. The isolates UFPI-59, UFPI-18 and UFPI-38 promoted the highest values of shoot and root dry weight, respectively. The isolates UFPI-32 promoted the highest values of nodule number, while UFPI-59 promoted the highest values of nodule dry weight. The isolates UFPI-38 and UFPI-59 promoted the highest accumulation of N. This study showed that seed size really influences lima bean growth, nodulation and BNF. Considering rhizobia isolates, UFPI-59, UFPI-38, and UFPI-18 contributed for plant growth, promoted better nodulation and effectiveness on biological N fixation.

RESUMO: Este estudo avaliou a atividade de isolados de rizóbios inoculados em sementes pequenas (11 mm) e grandes (18 mm) sobre o crescimento, nodulação e fixação de N de feijão-fava. Isolados selecionados de rizóbios foram comparados com uma estirpe de referência CIAT899 e dois controles sem inoculação. Sementes grandes contribuíram para maior crescimento de plantas, nodulação e fixação de N do que sementes pequenas. Os isolados UFPI-59, UFPI-18 e UFPI-38 promoveram os maiores valores de massa seca de parte aérea e raízes. Os isolados UFPI-32 e UFPI-59 promoveram os maiores valores de número e massa de nódulos, respectivamente. Os isolados UFPI-38 e UFPI-59 promoveram maior acúmulo de N. Este estudo mostrou que o tamanho de sementes influencia o crescimento, nodulação e fixação de N em feijão-fava. Considerando os isolados de rizóbios, UFPI-59, UFPI-38 e UFPI-18 contribuíram para o crescimento de plantas, promoveram melhor nodulação e eficiência na fixação de N.

Microorganisms in Biostimulants

In March 2016, the EU Commission presented a proposal for new regulations on fertilising material. The regulation includes product rules for a wide range of organic and inorganic products. Microbial biostimulants is one of the categories of products that are included. Biostimulants, in the draft EU regulation, are defined as fertilising materials that affect nutrient processes independently of the product's own nutrient content and with the purpose of improving nutrient utilisation, tolerance for abiotic stress or quality of the crop. Positive list in which species of these bacterial genera are listed: Azotobacter spp, Rhizobium spp., Azospirillum spp and Mycorrhizal fungi are a part of the regulation. Since the import and use of these organisms are the responsibility of both the Norwegian Food Safety Authority and the Norwegian Environment Agency, they asked VKM to submit a joint report on effects on health (humans, plants and animals), biodiversity and dispersal, quality of agricultural land and on soil environment. Conclusions: Health risks: Based upon our literature review, we have found no indication of any specific diseases in plants, animals or humans induced by the discussed microorganisms. A few reported cases of human disease are caused through wound infections or injections in immunocompromised patients. These represent a situation where any microorganism may induce infections and is not specific for the agents discussed in this report. In summary, the risk of any disease caused by the discussed microorganisms is considered negligible. Environmental risks: In soil the biodiversity, competition, adaptation and functional redundancy of microorganisms are extremely high. This means that introduced microorganisms have a very small chance for establishing, and even less so for affecting biodiversity and soil functioning. Introduction of nitrogen fixing species or fungi that can transport P to plants (mycorrhiza) will lead to an increase in the primary production. However, even a large increased activity for these processes will not outcompete naturally occurring symbiotic N-fixation or growth of inherently non-mycorrhizal plant species. Thus, the risks associated with introduced non-pathogenic microorganisms are very low.

Respuesta del simbiosistema frijol (Phaseolus vulgaris L.) y Rhizobium tropici CIAT899 ante el efecto alelopático de Ipomoea purpurea L. Roth / Responses of the common bean (Phaseolus vulgaris L.) and Rhizobium tropici CIAT899 symbiosystem to induced allelopathy by Ipomoea purpurea L. Roth

La alelopatía es un fenómeno que involucra la producción de metabolitos secundarios que influyen en el crecimiento de las plantas, pero este potencial alelopático ha sido poco estudiado en la simbiosis rizobio-leguminosa. Esta investigación tuvo los siguientes objetivos: 1) evaluar el potencial alelopático de lixiviados acuosos de Ipomoea purpurea L. Roth en la germinación de semillas y en el crecimiento radical de plántulas de frijol (Phaseolus vulgaris L.); 2) determinar el efecto de estos lixiviados en el crecimiento in vitro de Rhizobium tropici CIAT899, y 3) evaluar el potencial alelopático de I. purpurea en el crecimiento, la fisiología y la nodulación de frijol en simbiosis con R. tropici. Tanto el lixiviado acuoso de raíz como el de la parte aérea de I. purpurea estimularon la germinación de semillas de frijol y la elongación radical. El crecimiento in vitro de R. tropici fue inhibido al aplicar los 2 tipos de lixiviado. La presencia de I. purpurea tuvo un efecto negativo en el crecimiento y en las respuestas fisiológicas de las plantas de frijol, que fue atenuado cuando las plantas fueron inoculadas con Rhizobium tropici; no obstante, la nodulación asociada a esta bacteria fue afectada en presencia de la planta alelopática. Los resultados indican que la simbiosis de rizobios en las raíces de frijol es un elemento importante en la atenuación de los danos producidos por la planta alelopática I. purpurea.

Allelopathy is a phenomenon that involves the production of secondary metabolites that influence the growth of plants and microorganisms; however, this alellopathic effect has been scarcely studied on the rhizobia-legume symbiosis. The aims of this research were 1) to assess the allelopathic potential of aqueous extracts of Ipomoea purpurea L. Roth on seed germination and root length of common bean seedlings (Phaseolus vulgaris L.), 2) to determine its effects on the in vitro growth of Rhizobium tropici CIAT899, and 3) to evaluate the allelopathic potential of I. purpurea on the growth, nodulation and physiology of common bean plants inoculated with R. tropici. After 48 h, 15% of the aqueous root extract of I. purpurea stimulated seed germination, whereas 4% of the aqueous shoot extracts stimulated such germination. Both the root or shoot extracts stimulated seed germination and e root length. In vitro growth of R. tropici was inhibited as a result of the application of both aqueous extracts. The presence of I. purpurea negatively affected both the growth and physiological responses of common bean plants, and this effect was attenuated after the inoculation of R. tropici; nevertheless, this allelopathic plant affected root nodulation. Our results suggest that the symbiosis of rhizobia and roots of common bean plants is an important element for attenuating the negative effects caused by the allelopathic plant.

Effect of organic and conventional farming practices on soil microbial population

Aim: Microbial community has an integral role in farming, but there is limited understanding of the complex response of microbial populations to organic and conventional farming systems. Therefore, the present study was carried out to study the effect of organic and conventional farming practices on soil microbial population in Haryana. Methodology: Fifty surface soil samples (0-15 cm) were collected from organic and their adjoining conventional farms at 11 districts of Haryana. Soil samples were processed and analyzed for Rhizobium, Azotobacter, Azospirillium and phosphorous solubilizing bacterial (PSB) counts for the two types of farming systems. Results: In comparison to conventional farming system, overall, population of PSB (which was 25.71×104 CFU g-1 soil) increased significantly to 36.91×104 CFU g-1 soil (an increase of 43.5%). Similarily, Rhizobium population in organic farming system increased from 29.26×104 CFU g-1 soil to 42.14×104 CFU g-1 soil (an increase of 44.1%). The population of Azotobacter increased significantly from 15.83×104 to 22.01×104 CFU g-1 soil (39.0%), while Azospirillium population increased from 13.66×104 to 20.10×104 CFU g-1 with an increase of 47.1%. Thus, it is clear from the results that organic nutrient sources showed a stimulating influence on the microbial populations of organic farming. Interpretation: Higher microbial population recorded in organic farming in comparison to conventional farming leads to better soil health and increased productivity.

Genomic comparisons of Rhizobium species using in silico AFLP-PCR, endonuclease restriction, and AMPylating enzymes

Background: The whole-genome sequences of nine Rhizobium species were evaluated using different in silico molecular techniques such as AFLP-PCR, restriction digest, and AMPylating enzymes. The entire genome sequences were aligned with progressiveMauve and visualized by reconstructing phylogenetic tree using NTSYS pc 2.11X. The "insilico.ehu.es" was used to carry out in silico AFLP-PCR and in silico restriction digest of the selected genomes. Post-translational modification (PTM) and AMPylating enzyme diversity between the proteome of Rhizobium species were determined by novPTMenzy. Results: Slight variations were observed in the phylogeny based on AFLP-PCR and PFGE and the tree based on whole genome. Results clearly demonstrated the presence of PTMs, i.e., AMPylation with the GS-ATasE (GlnE), Hydroxylation, Sulfation with their domain, and Deamidation with their specific domains (AMPylating enzymes) GS-ATasE (GlnE), Fic, and Doc (Phosphorylation); Asparagine_hydroxylase and Collagen_prolyl_lysyl_hydroxylase; Sulfotransferase; and CNF (Cytotoxic Necrotizing Factors), respectively. The results pertaining to PTMs are discussed with regard to functional diversities reported in these species. Conclusions: The phylogenetic tree based on AFLP-PCR was slightly different from restriction endonuclease- and PFGE-based trees. Different PTMs were observed in the Rhizobium species, and the most prevailing type of PTM was AMPylation with the domain GS-ATasE (GlnE). Another type of PTM was also observed, i.e., Hydroxylation and Sulfation, with the domains Asparagine_hydroxylase and Collagen_prolyl_lysyl_hydroxylase and Sulfotransferase, respectively. The deamidation type of PTM was present only in Rhizobium sp. NGR234. How to cite: Qureshi MA, Pervez MT, Babar ME, et al. Genomic comparisons of Rhizobium species using in silico AFLP-PCR, endonuclease restrictions and ampylating enzymes.

Inhibitory Effect of Rhizobia Isolated from Several Leguminous against Phytopathogenic Fungi

Aims: This study was carried out to evaluate the antagonistic effect of ten isolated characterized Rhizobium sp. and three referenced strains against aggressive phytopathogenic fungi Fusarium spp., Aspergillus spp., Penicillium spp., Alternaria spp., Humicola spp. and Cladosporium spp. isolated from infected and wilted plants in vitro and in vivo. Study Design:  First, we have ten strains of rhizobia isolated from leguminous and characterized, after that,  some strains of fungi were isolated from infected  and wilt plants,  such as Fusarium, Aspergillus, Penicillium,  Alternaria, Humicola and Cladosporium. Finally, The investigation of the potential of the isolated rhizobia and three referenced strains was evaluated in dual culture, in pots experiments and on seeds. Place and Duration of Study: The study was carried out at the Department of Microbiology, Faculty of Nature and Life Sciences, Laboratory of Applied Microbiology, between April and November 2016. Methodology: Rhizobia isolates were identified upon their phenotypic traits as: the morphology of the colony, of the physiological characters (growth temperature, salt tolerance, resistance to antibiotics, metabolism of carbon source, generation time…) and also the production of extracellular metabolites as siderophores and proteases. Fungal isolates were identified by their macroscopic and microscopic characters. The antagonistic effect of rhizobia against phytopathogenic fungi was examined in vitro by: confrontation in Petri dishes and inoculation of seeds; and in vivo by inoculation of plants. Results: The isolated rhizobia were resistant to penicillin and amoxicillin with generation time ranged from 1.9 to 6.4 h, they were able to grow at temperatures from 4°C to 37°C, tolerate salt concentration (0.5 –2%) and produce siderophores and proteases. The results demonstrated the effectiveness of the rhizobia isolates and the referenced strains against the fungi isolates in vitro and in vivo. In dual culture, all rhizobia isolates inhibited the mycelial growth of the pathogens. The best disease control was obtained with isolate F3 from faba bean which inhibited the fungal growth with more than 70%. The highest inhibition growth was obtained against Alternaria spp.2, Penicillium spp.2, Cladosporium spp. and Humicola spp. with an inhibition rate ranging from 90 to 96%. In pot experiments, Rhizobia isolates from chickpea, lentil and faba bean reduced significantly all disease incidence  with more than 75%; where the best fight was observed in lentil plants, while in faba bean no wilted plants were observed. Seeds inoculated with rhizobia and fungi in Petri dishes showed that isolates from faba bean and lentil were the most effective in reducing fungi disease incidence. Conclusion: Rhizobia have a high potentiality to inhibit the growth of tested pathogens and could be fielded within an integrated disease management package.

In silico analysis of a Rhizobium sp. RC1 putative haloalkanoic permease sequence motif and classification

Aims@#The transport of haloalkanoic acids (haloacids) is important in the metabolism of haloacid pollutants by bacteria. In this study, a computational analysis of Rhizobium sp. RC1 haloacid permease (DehrP) amino acid sequence was conducted to identify its subfamily, sequence motifs and evolutionary position among closely related transporters. @*Conclusion, significance and impact of study@#Blast search in the Pfam and Transmembrane Classification Databases was used to establish the classification and the subfamily of DehrP. Clustal omega sequence alignment approach and MEME Suite motif-based analysis tools were used to locate the transporter motifs of DehrP. Dotplots of DehrP sequence was computed using the EMBOSS Dotmatcher. MEGA7 software was used to analyze the phylogenetic position of DehrP among closely related symporters in the Transmembrane Classification Database. Comparative analysis by Pfam shows that DehrP is a member of the Major Facilitator Superfamily (#2.A.1). PSI-Blast against the Transmembrane Classification Database shows that DehrP is significantly aligned with a subfamily of transporters called the Metabolite: H+ Symporters (#2.A.1.6). DehrP has six similar sequence motifs with the Metabolite: H+ Symporter proteins including the functional motif of GXXXDRXGRR. DehrP is evolutionarily related to Burkholderia caribensis MBA4 Haloacid: H+ Symporters (Dehp2 and Deh4p). @*Methodology and results@#Based on sequence similarity, DehrP is a Major Facilitator Superfamily protein that belongs to the Metabolite: H+ Symporter protein subfamily which might coordinate the transport of a haloacid coupled with a proton (H+). Mutagenesis of DehrP sequence motifs might be useful in the engineering of Rhizobium sp. RC1 for efficient uptake and degradation of haloacids.

Roles of quorum sensing molecules from Rhizobium etli RT1 in bacterial motility and biofilm formation

ABSTRACT Strain RT1 was isolated from root nodules of Lens culinaris (a lentil) and characterized as Rhizobium etli (a Gram-negative soil-borne bacterium) by 16S rDNA sequencing and phylogenetic analysis. The signaling molecules produced by R. etli (RT1) were detected and identified by high-performance liquid chromatography coupled with mass spectrometry. The most abundant and biologically active N-acyl homoserine lactone molecules (3-oxo-C8-HSL and 3-OH-C14-HSL) were detected in the ethyl acetate extract of RT1. The biological role of 3-oxo-C8-HSL was evaluated in RT1. Bacterial motility and biofilm formation were affected or modified on increasing concentrations of 3-oxo-C8-HSL. Results confirmed the existence of cell communication in RT1 mediated by 3-oxo-C8-HSL, and positive correlations were found among quorum sensing, motility and biofilm formation in RT1.