Direct effect of biocontrol agents on wilt and root-rot diseases of sesame

In Egypt, sesame cultivation is subject to attack by wilt and root-rot diseases caused by Fusarium oxysporum f.sp. sesami (Zap) Cast. and Macrophomina phaseolina (Maubl) Ashby causing losses in quality and quantity of sesame seed yield. Bacillus subtilis and Trichoderma viride isolates which were isolated from sesame rhizosphere were the most effective to antagonise fungal pathogens, causing high reduction of hyphal fungal growth. Trichoderma viride was found to be mycoparasitic on Fusarium oxysporum f.sp. sesami and M. phaseolina causing morphological atternation of fungal cells and sclerotial formation. In general, Bacillus subtilis, T. viride, avirulent Fusarium oxysporum isolate and Glomus spp. (Amycorrhizae) significantly reduced wilt and root-rot incidence of sesame plants at artificially infested potted soil by each one or two pathogens. Data obtained indicate that Glomus spp significantly reduced wilt and disease severity development on sesame plants followed by T. viride. Meanwhile, avirulent Fusarium oxysporum isolate followed by Glomus spp. were effective against root-rot disease incidence caused by M. phaseolina. Glomus spp. followed by B. subtilis significantly reduced wilt and root-rot disease of sesame plants. All biotic agents significantly reduced F. oxysporum f.sp. sesami and M. phaseolina counts in sesame rhizosphere at the lowest level. Glomus spp. and the avirulent isolate of F. oxysporum eliminated M. phaseolina in sesame rhizosphere. Meanwhile T. viride was the best agent at reducing F. oxysporum at a lower level than other treatments. Application of VA mycorrhizae (Glomus spp.) in fields naturally infested by pathogens significantly reduced wilt and root-rot incidence and it significantly colonised sesame root systems and rhizospheres compared to untreated sesame transplantings.     

Biological control of root rot fungus <Emphasis Type="Italic">Macrophomina phaseolina</Emphasis> and growth enhancement of <Emphasis Type="Italic">Pinus roxburghii</Emphasis> (Sarg.) by rhizosphere competent <Emphasis Type="Italic">Bacillus subtilis</Emphasis> BN1

Bacterial isolates having antifungal and good plant growth-promoting attributes were isolated from chir-pine (Pinus roxburghii) rhizosphere. An isolate, Bacillus subtilis BN1 exhibited strong antagonistic activity against Macrophomina phaseolina, and other phytopathogens including Fusarium oxysporum and Rhizoctonia solani. It was characterized and selected for the present studies. BN1 resulted in vacuolation, hyphal squeezing, swelling, abnormal branching and lysis of mycelia. The cell-free culture filtrate of BN1 inhibited the growth of M. phaseolina. Pot trial study resulted in statistically significant increase in seedling biomass besides reduction in root rot symptoms in chir-pine seedlings. BN1 treatment resulted in 43.6% and 93.54% increases in root and shoot dry weights respectively, as compared to control. Also, 80–85% seed viability was recorded in treatments receiving BN1 either alone or in the presence of M. phaseolina, compared to 54.5% with M. phaseolina. Bioinoculant formulation study suggested that maximum viability of bacteria was in a sawdust-based carrier. B. subtilis BN1 produced lytic enzymes, chitinase and β-1,3-glucanase, which are known to cause hyphal degradation and digestion of the cell wall component of M. phaseolina. In the presence of M. phaseolina, population of B1 was 1.5 × 10⁴ c.f.u. g⁻¹ root after one month, which increased to 4.5 × 10⁴ c.f.u. g⁻¹ root in three months. Positive root colonization capability of B. subtilis BN1 proved it as a potent biocontrol agent.     

The synthetic strigolactone GR24 influences the growth pattern of phytopathogenic fungi

Strigolactones that are released by plant roots to the rhizosphere are involved in both plant symbiosis with arbuscular mycorrhizal fungi and in plant infection by root parasitic plants. In this paper, we describe the response of various phytopathogenic fungi to the synthetic strigolactone GR24. When GR24 was embedded in the growth medium, it inhibited the growth of the root pathogens Fusarium oxysporum f. sp. melonis, Fusarium solani f. sp. mango, Sclerotinia sclerotiorum and Macrophomina phaseolina, and of the foliar pathogens Alternaria alternata, Colletotrichum acutatum and Botrytis cinerea. In the presence of this synthetic strigolactone, intense branching activity was exhibited by S. sclerotiorum, C. acutatum and F. oxysporum f. sp. melonis. Slightly increased hyphal branching was observed for A. alternata, F. solani f. sp. mango and B. cinerea, whereas suppression of hyphal branching by GR24 was observed in M. phaseolina. These results suggest that strigolactones not only affect mycorrhizal fungi and parasitic plants, but they also have a more general effect on phytopathogenic fungi.     

In vitro biocontrol activity of halotolerant Streptomyces aureofaciens K20: A potent antagonist against Macrophomina phaseolina (Tassi) Goid

A halotolerant actinobacterial strain isolated from salinity affected soil of Eastern Indo-Gangetic plains (IGP), Uttar Pradesh, India, was characterised for its antagonistic potential against Macrophomina phaseolina by dual-culture assay. It was shown to effectively inhibit the growth of M. phaseolina with an inhibition zone of 27 ± 1.33 mm. Further the actinobacterial strain was evaluated for its plant growth promoting (PGP) properties and its ability to produce biocontrol related extracellular enzymes viz. amylase, protease, cellulase, chitinase, gelatinase and urease. The results revealed that the actinobacterial strain had PGP potential along with positive assay for amylase, chitinase and urease. The interaction study between antagonist strain and fungal pathogen, performed by scanning electron microscopy technique revealed that the actinobacterium was able to damage fungal mycelia may be due to chitinase, establishing its role as a potential antagonist against M. phaseolina. The actinobacterial isolate was characterised by 16S rDNA gene sequencing, and was identified as Streptomyces genera. The identified gene sequence was deposited to NCBI GenBank with an accession number KP331758.     

Influence of adenine,isopentyl alcohol and Azotobacter chroococcum on the growth of Raphanus sativus

The effect of adenine (ADE), isopentyl alcohol (IA) and a cytokinin-producing bacterium, Azotobacter chroococcum, on the morphological plant characteristics of Raphanus sativus (radish) was studied in sand under axenic-inoculated conditions and in soil under glasshouse and field conditions. The application of the combination of 0.2 mg kg^–1 ADE, 13 mg kg^–1 IA plus the inoculum enhanced the dry weight of root and shoot tissues, leaf area and chlorophyll a content, to a much greater degree than when in the presence of the cytokinin precursors (ADE or IA) or the bacterium alone. Enhanced plant growth observed under axenic conditions upon the addition of ADE and IA indicated that the plant has the ability to assimilate and utilize ADE and IA for growth and metabolism. While the addition of the inoculum without precursors was also stimulatory, greater enhancement of plant growth was observed following the application of ADE, IA and A. chroococcum together being attributed primarily to the increase in microbial production of cytokinins within the rhizosphere.     

Establishment of phosphate-solubilizing strains of Azotobacter chroococcum in the rhizosphere and their effect on wheat cultivars under green house conditions

A pot experiment was conducted in the green house to investigate the establishment of phosphate solubilizing strains of Azotobacter chroococcum, including soil isolates and their mutants, in the rhizosphere and their effect on growth parameters and root biomass of three genetically divergent wheat cultivars (Triticum aestivum L.). Five fertilizer treatments were performed: Control, 90 kg N ha^—1, 90 kg N + 60 kg P₂O₅ ha^—1, 120 kg N ha^—1 and 120 kg N + 60 kg P₂O₅ ha^—1. Phosphate solubilizing and phytohormone producing parent soil isolates and mutant strains of A. chroococcum were isolated and selected by an enrichment method. In vitro phosphate solubilization and growth hormone production by mutant strains was increased compared with soil isolates. Seed inoculation of wheat varieties with P solubilizing and phytohormone producing A. chroococcum showed better response compared with controls. Mutant strains of A. chroococcum showed higher increase in grain (12.6%) and straw (11.4%) yield over control and their survival (12—14%) in the rhizosphere as compared to their parent soil isolate (P4). Mutant strain M37 performed better in all three varieties in terms of increase in grain yield (14.0%) and root biomass (11.4%) over control.     

Influence of adenine,isopentyl alcohol and Azotobacter chroococcum on the vegetative growth of Zea mays

Glasshouse experiments were conducted to evaluate the influence of pretested cytokinin precursors, adenine (ADE) and isopentyl alcohol (IA), and a cytokinin producing bacterium, Azotobacter chroococcum added to soil, on the vegetative growth of maize (Zea mays L.). The combination of 2.0 mg ADE kg^-1 soil, 13 mg IA kg^-1 soil, plus an inoculum of A. chroococcum was the most effective in enhancing the vegetative growth of maize compared with the application of ADE plus IA, ADE plus A. chroococcum, or ADE, IA or A. chroococcum alone. The dry weight of root and shoot tissues was increased up to 5.57- and 5.01-fold, respectively, in comparison to the controls; however, the root/shoot ratios were similar. The increases in shoot height, internodal distance, stem and leaf width over the controls under the optimum treatment were: 2.07-, 2.81-, 1.46-, and 2.11-fold, respectively. The improvement in plant yield was primarily attributed to A. chroococcum production of cytokinins in the rhizosphere.     

Temperature response,pathogenicity, seed infection and mutant evaluation against Macrophomina phaseolina causing charcoal rot disease of sesame

Charcoal rot caused by Macrophomina phaseolina is a serious disease of sesame in Pakistan. M. phaseolina sesame isolate was subjected to growth rate test at 10, 15, 20, 25, 30, 35 and 40°C. The optimum temperature for fungal growth and microsclerotia production was found to be 30–35°C. Gray to black, radial fungal colonies with intermediate mycelial growth and jet black oval to round microsclerotia were observed at this optimum range. M. phaseolina was found to be pathogenic against all the 18 tested plant species and this pathogenicity proved its necrophytic behavior. Seed infection efficiency of M. phaseolina was 100% with significant reduction in seed index. For two consecutive years 21 mutants/varieties were screened in the field for their reactions to charcoal rot disease. During 2007 three mutants NS11704S1, NS11304S2 and NS26004 were ranked as resistant while others were moderately resistant to highly susceptible. During 2008 all mutants showed a susceptible to highly susceptible reaction with variable disease reactions. All over screening results revealed that four mutants viz, NS13P1, NS163-1, NS270P1 and NS26004 showed about 50% stand with consistent performance during both years under optimum disease conditions and can be used to manage the disease following the disease management strategies, however in the future improvement for high seed yield along with resistance is a prerequisite for sustainable high production.     

Management of disease complex of balsam caused by Meloidogyne javanica and Macrophomina phaseolina by using biofertilisers and pesticides

An investigation was conducted to study the effect of biofertilisers (Glomus fasciculatum, Azospirillum brasilense, Azotobacter chroococcum and Micro Phos) and pesticides (carbofuran and bavistin) on the management of root-rot and root-knot disease complex of balsam. The individual application of biofertilisers (G. fasciculatum, A. brasilense and A. chroococcum) significantly improved the plant growth parameters viz., length, dry weight and number of flowers compared to untreated-uninoculated plants. The simultaneous inoculation of plant with Meloidogyne javanica and Macrophomina phaseolina in the pots treated with either of the biofertilisers (G. fasciculatum, A. brasilense and A. chroococcum) and pesticides (carbofuran/bavistin) significantly improved the plant growth parameters and reduced the reproduction factor, number of galls and intensity of root-rot compared to untreated-inoculated plants. On the other hand, the plants treated with Micro Phos neither significantly improved the plant growth parameters nor reduced the reproduction factor, number of galls and intensity of root-rot. Among the biofertilisers and pesticides, carbofuran was found to be the most effective in the management of disease complex of balsam followed by bavistin, G. fasciculatum, A. brasilense and A. chroococcum.     

Macrophomina phaseolina – Meloidogyne javanica disease complex in balsam (Impatiens balsamina): a new report

Balsam seedlings were inoculated with root-knot nematode Meloidogyne javanica Race-2 and Macrophomina phaseolina either individually or concomitantly, as well as sequentially with an interval of 15?days between the nematode or fungal inoculations to determine whether the interaction was concomitant or sequential. The greater reduction in plant growth characters was observed in the plants inoculated with M. javanica and M. phaseolina, either concomitantly or sequentially as compared to their individual inoculation. However, the highest reduction in plant growth characters were recorded in the plants inoculated with M. javanica Race-2 15?days prior to M. phaseolina followed by concomitant-inoculated M. javanica Race-2 and M. phaseolina, and M. phaseolina 15?days prior to M. javanica. The number of galls/root system and the reproduction factor of the root-knot nematode was reduced in the presence of root-rot fungus. The intensity of root-rot caused by M. phaseolina increased in the presence of root-knot nematode M. javanica as compared to when M. phaseolina was inoculated individually. Moreover, stem and collar-rot symptoms caused by M. phaseolina appeared only in the presence of root-knot nematode.     

Plant defense approach of Bacillus subtilis (BERA 71) against Macrophomina phaseolina (Tassi) Goid in mung bean

This study was aimed to elucidate the mitigation mechanism of an endophytic bacterium, Bacillus subtilis (BERA 71) against Macrophomina phaseolina (Tassi) Goid disease in mung bean. M. phaseolina reduced the plant growth by inducing disease, hydrogen peroxide (H₂O₂) and lipid peroxidation. The inoculation of B. subtilis to diseased plants increased chlorophyll, ascorbic acids, and superoxide dismutase, catalase, peroxidase, ascorbate peroxidase and glutathione reductase activities, and while inhibited H₂O₂ and lipid peroxidation for enhancing plant growth. In addition, B. subtilis association in plants mitigated the M. phaseolina infection due to increase of indole acetic acids and indole butyric acid, and also a decrease of abscisic acid. However, the nutrients (N, K, Ca, Mg, Zn, Cu, Mn and Fe) were increased, except Na in M. phaseolina diseased plants treated with B. subtilis. The result of this study suggests that B. subtilis interaction with plants can modulate the metabolism of pigments, hormones, antioxidants and nutrients against M. phaseolina to induce disease resistance in mung bean.     

Evaluation of Streptomyces spp. and Bacillus spp. for biocontrol of Fusarium wilt in chickpea (Cicer arietinum L.)

A study was carried out to test direct and indirect antagonistic effect against Fusarium wilt, caused by Fusarium oxysporum f. sp. ciceri (FOC), and plant growth-promoting (PGP) traits of bacteria isolated from rhizosphere soils of chickpea (Cicer arietinum L.). A total of 40 bacterial isolates were tested for their antagonistic activity against FOC and of which 10 were found to have strong antagonistic potential. These were found to be Streptomyces spp. (five isolates) and Bacillus spp. (five isolates) in the morphological and biochemical characterisation and 16S rDNA analysis. Under both greenhouse and wilt sick field conditions, the selected Streptomyces and Bacillus isolates reduced disease incidence and delayed expression of symptoms of disease, over the non-inoculated control. The PGP ability of the isolates such as nodule number, nodule weight, shoot weight, root weight, grain yield and stover yield were also demonstrated under greenhouse and field conditions over the non-inoculated control. Among the ten isolates, Streptomyces sp. AC-19 and Bacillus sp. BS-20 were found to have more potential for biocontrol of FOC and PGP in chickpea. This investigation indicates that the selected Streptomyces and Bacillus isolates have the potential to control Fusarium wilt disease and to promote plant growth in chickpea.     

Alleviating salt stress in tomato seedlings using Arthrobacter and Bacillus megaterium isolated from the rhizosphere of wild plants grown on saline–alkaline lands

Salt-induced soil degradation is common in farmlands and limits the growth and development of numerous crop plants in the world. In this study, we isolated salt-tolerant bacteria from the rhizosphere of Tamarix chinensis, Suaeda salsa and Zoysia sinica, which are common wild plants grown on a saline–alkaline land, to test these bacteria's efficiency in alleviating salt stress in tomato plants. We screened out seven strains (TF1–7) that are efficient in reducing salt stress in tomato seedlings. The sequence data of 16S rRNA genes showed that these strains belong to Arthrobacter and Bacillus megaterium. All strains could hydrolyze casein and solubilize phosphate, and showed at least one plant growth promotion (PGP)-related gene, indicating their potential in promoting plant growth. The Arthrobacter strains TF1 and TF7 and the Bacillus megaterium strain TF2 and TF3 could produce indole acetic acid under salt stress, further demonstrating their PGP potential. Tomato seed germination, seedling length, vigor index, and plant fresh and dry weight were enhanced by inoculation of Arthrobacter and B. megaterium strains under salt stress. Our results demonstrated that salt-tolerant bacteria isolated from the rhizosphere of wild plants grown on saline–alkaline lands could be used for alleviating salt stress in crop plants.     

Proteome reference map for the plant growth‐promoting bacterium Pseudomonas putida UW4

A proteome reference map containing 326 2‐D gel spots representing 275 different proteins was constructed for the plant growth‐promoting bacterium Pseudomonas putida UW4. Protein identifications were obtained using Q‐TOF MS/MS spectra matching to homologous proteins from other Pseudomonas strains and confirmed by PMF analysis. This data set is accessible at http://world‐2dpage.expasy.org/repository/ and will aid in further characterization of Pseudomonas strains and interactions of plant growth‐promoting bacterium with the plant rhizosphere environment.     

Potential role of rhizobia to enhance chickpea-growth and yield in low fertility-soils of Tunisia

Plant growth-promoting rhizobacteria are bacteria that improve plant growth and reduce plant pathogen damages. In this study, 100 nodule bacteria were isolated from chickpea, screened for their plant growth-promoting (PGP) traits and then characterised by PCR-RFLP of 16 S rDNA. Results showed that most of the slow-growing isolates fixed nitrogen but those exhibiting fast-growth did not. Fourteen isolates solubilized inorganic phosphorus, 16 strains produced siderophores, and 17 strains produced indole acetic acid. Co-culture experiments identified three strains having an inhibitory effect against Fusarium oxysporum, the primary pathogenic fungus for chickpea in Tunisia. Rhizobia with PGP traits were assigned to Mesorhizobium ciceri, Mesorhizobium mediterraneum, Sinorhizobium meliloti and Agrobacterium tumefaciens. We noted that PGP activities were differentially distributed between M. ciceri and M. mediterraneum. The region of Mateur in northern Tunisia, with clay–silty soil, was the origin of 53% of PGP isolates. Interestingly, we found that S. meliloti and A. tumefaciens strains did not behave as parasitic nodule-bacteria but as PGP rhizobacteria useful for chickpea nutrition and health. In fact, S. meliloti strains could solubilize phosphorus, produce siderophore and auxin. The A. tumefaciens strains could perform the previous PGP traits and inhibit pathogen growth also. Finally, one candidate strain of M. ciceri (LL10)—selected for its highest symbiotic nitrogen fixation and phosphorus solubilization—was used for field experiment. The LL10 inoculation increased grain yield more than three-fold. These finding showed the potential role of rhizobia to be used as biofertilizers and biopesticides, representing low-cost and environment-friendly inputs for sustainable agriculture.

     

Screening of bacteria of the genus Bacillus for the control of the plant-pathogenic fungus Macrophomina phaseolina

This study evaluated the efficiency of 19 Bacillus isolates, obtained from the rhizosphere and rhizoplane of wild and cultivated castor bean plants, to control the pathogenic fungus Macrophomina phaseolina. Using in vitro assays, we examined the antifungal effects of volatile and non-volatile compounds, the production of siderophores and the activity of chitinase in these isolates. In vivo experiments were conducted to determine the potential of the Bacillus isolates to colonise castor bean plant roots and to control the fungus. In general, results showed that isolates from wild castor bean, compared with isolates from cultivated castor bean, were more efficient producers of antifungal compounds, better colonisers of plant roots and more effective protectors of plant seedlings against infection with M. phaseolina. Altogether, isolate RP 5, originating from the rhizoplane of wild castor bean, was the most promising candidate for future evaluation as a biological control agent of M. phaseolina.     

Suppression of Charcoal Rot of Chickpea by Fluorescent <Emphasis Type="Italic">Pseudomonas</Emphasis> Under Saline Stress Condition

The ability of fluorescent Pseudomonas strain EKi, in production of biocontrol and plant growth promotory (PGP) metabolites under saline stress was evaluated. Strain EKi could tolerate NaCl up to 1,550 mM and showed biocontrol of Macrophomina phaseolina (76.19%) in the presence of up to 400 mM NaCl. Strain EKi was able to produce IAA, siderophore and pyocyanin with gradual reduction of up to 76.31, 45.46, and 48.99%, respectively, as NaCl concentration increased from 0 to 500 mM. Reduced growth rate resulted in delayed induction of IAA, siderophore and pyocyanin by the PGPR. Thin layer chromatography of chloroform extract from non-stressed and salt stressed EKi, and inhibition of M. phaseolina by purified pyocyanin clearly indicated its role in biocontrol. In vitro and in vivo results showed the growth promotion and charcoal rot disease suppression of chickpea by strain EKi under both non-stressed and saline stress. There was 76.75 and 65.25% reduction of disease incidence in non-saline and saline conditions, respectively, in vitro conditions. In presence of M. phaseolina strain EKi brought about 67.65 and 58.45% reduction of disease incidence in non-saline and saline soil, respectively.     

Control of charcoal root rot in <Emphasis Type="Italic">Pinus radiata</Emphasis> nurseries with antagonistic bacteria

The objective of this study was to determine the potential of antagonistic bacteria to control charcoal root rot of coniferous seedlings caused by Macrophomina phaseolina (Tassi) Goid. in forest nurseries. Bacterial isolates were collected from nurseries located between Region Metropolitana and the VIII Region of Chile. Antagonists were initially evaluated in in vitro assays based on the ability to inhibit mycelial growth of M. phaseolina, and subsequently in two trials in a Pinus radiata nursery with a natural infestation of the pathogen. For nursery trials, the isolates were selected according to in vitro and field trial pathogen controls. The bacteria were applied as seed treatments and via water irrigation. The trials were conduced in a completely randomized block design. Among 568 bacterial isolates tested in vitro, 19.8% displayed some capacity to inhibit the mycelial growth of M. phaseolina, with inhibition between 1.7% and 67.6%. In the first nursery trial, Bacillus amyloliquefaciens VII 015, Bacillus pumilus IX 030, Bacillus stearothermophilus TM 008 and other two Bacillus sp. (VI 009 and IX 049) strains, significantly reduced the total, pre- and post-emergency mortality of seedlings, but no isolate reduced the incidence of M. phaseolina in seedlings. In the second trial, Bacillus sp. IX 049, VI 099, B. subtilis (IX 007) and a non-identified isolate V 005, decreased the incidence of charcoal root rot. It is concluded that the best of these bacterial antagonists have the potential to control M. phaseolina in P. radiata nurseries.     

Plant growth enhancement is not a conserved feature in the Caulobacter genus

Aims

Species within the Caulobacter genus have been termed ‘hub species’ in the plant microbiome. To understand these interactions, we assessed the interactions between several Caulobacter strains and a common host plant.

Methods

We identified a set of 11 Caulobacter strains that range in genetic diversity and tested them for their ability to increase the growth of Arabidopsis thaliana. In addition, biochemical assays were employed to determine if these Caulobacter strains produce common plant growth promoting (PGP) biosynthates. To identify potential PGP-related genes, genomic analyses were performed to compare the genomes of PGP Caulobacter strains to those of non-PGP Caulobacter strains.

Results

For the PGP Caulobacter strains, we observed that common PGP biosynthates did not contribute to the observed Caulobacter-mediated plant growth stimulation. Genomic analyses suggested that the genomes of PGP strains maintain similar metabolic pathways compared to those of non-PGP strains, and that common genes related to PGP factors do not explain the PGP mechanisms for the Caulobacter strains we analyzed.

Conclusions

Plant growth enhancement is not a conserved feature in the Caulobacter genus, and some Caulobacter strains even inhibit plant growth. Moreover, common PGP factors do not fully explain Caulobacter-mediated plant growth enhancement.

     

<Emphasis Type="Italic">Pseudomonas lurida</Emphasis> M2RH3 (MTCC 9245), a psychrotolerant bacterium from the Uttarakhand Himalayas,solubilizes phosphate and promotes wheat seedling growth

Pseudomonas lurida strain M2RH3 (MTCC 9245) is a Gram negative, non spore forming, fluorescent bacterium isolated from a high altitude rhizospheric soil from the Uttarakhand Himalayas. The identity of the bacterium was arrived by sequencing of the 16S rRNA gene and subsequent phylogenetic analysis. It grew and exhibited plant growth promoting traits at 4, 15 and 30°C, under in vitro conditions. The expression of plant growth promoting (PGP) traits by the bacterium was highest at 30°C, with a proportionate reduction in PGP activity at lower temperatures. Determination of phosphate solubilization by the bacterium at three incubation temperatures revealed a steady increase in the soluble P levels across the incubation temperatures, coupled with a concomitant drop in the pH levels of the culture supernatant, till the 14th day of incubation. Seed bacterization with the isolate positively influenced the growth and nutrient uptake parameters of wheat seedlings cv. VL 804 in pot culture conditions at controlled cold growing temperature. This is an early report on the phosphate solubilization and plant growth promotion by Pseudomonas lurida, which is a relatively new species of the genus Pseudomonas and opens up a hitherto unknown facet of this bacterium.