Transcriptomic characterization of Trichoderma harzianum T34 primed tomato plants: assessment of biocontrol agent induced host specific gene expression and plant growth promotion.

In this study, we investigated the intricate interplay between Trichoderma and the tomato genome, focusing on the transcriptional and metabolic changes triggered during the late colonization event. Microarray probe set (GSE76332) was utilized to analyze the gene expression profiles changes of the un-inoculated control (tomato) and Trichoderma-tomato interactions for identification of the differentially expressed significant genes. Based on principal component analysis and R-based correlation, we observed a positive correlation between the two cross-comaparable groups, corroborating the existence of transcriptional responses in the host triggered by Trichoderma priming. The statistically significant genes based on different p-value cut-off scores [(padj-values or q-value); padj-value < 0.05], [(pcal-values); pcal-value < 0.05; pcal < 0.01; pcal < 0.001)] were cross compared. Through cross-comparison, we identified 156 common genes that were consistently significant across all probability thresholds, and showing a strong positive corelation between p-value and q-value in the selected probe sets. We reported TD2, CPT1, pectin synthase, EXT-3 (extensin-3), Lox C, and pyruvate kinase (PK), which exhibited upregulated expression, and Glb1 and nitrate reductase (nii), which demonstrated downregulated expression during Trichoderma-tomato interaction. In addition, microbial priming with Trichoderma resulted into differential expression of transcription factors related to systemic defense and flowering including MYB13, MYB78, ERF2, ERF3, ERF5, ERF-1B, NAC, MADS box, ZF3, ZAT10, A20/AN1, polyol sugar transporter like zinc finger proteins, and a novel plant defensin protein. The potential bottleneck and hub genes involved in this dynamic response were also identified. The protein-protein interaction (PPI) network analysis based on 25 topmost DEGS (pcal-value < 0.05) and the Weighted Correlation Gene Network Analysis (WGCNA) of the 1786 significant DEGs (pcal-value < 0.05) we reported the hits associated with carbohydrate metabolism, secondary metabolite biosynthesis, and the nitrogen metabolism. We conclude that the Trichoderma-induced microbial priming re-programmed the host genome for transcriptional response during the late colonization event and were characterized by metabolic shifting and biochemical changes specific to plant growth and development. The work also highlights the relevance of statistical parameters in understanding the gene regulatory dynamics and complex regulatory networks based on differential expression, co-expression, and protein interaction networks orchestrating the host responses to beneficial microbial interactions.

Portraying manganese biofilms via a merger of EPR spectroscopy and cathodic polarization.

Microbial biofilms on stainless steel surfaces exposed to water from a freshwater pond were dominated by manganese-oxidizing bacteria, as initially diagnosed by microscopy and elemental analysis. The application of electron paramagnetic resonance (EPR) spectroscopy revealed conspicuous sextet (six-line) patterns that intensified with immersion time, implying the gradual accumulation of Mn(II) in the biofilms. Correspondingly, cathodic polarization designated the manganese oxide (MnOx) reduction peak in the form of a distinctive 'nose', which grew increasingly more negative with biofilm growth. The progressive expansion of cathodic current densities and the concurrent area-under-the-curve also allowed the quantification of microbially mediated MnOx deposition. Furthermore, the merger of EPR and cathodic polarization techniques yielded key insights, in tandem with Mn speciation data, into the pathways of microbial manganese transformations in biofilms, besides providing meaningful interpretations of prevailing literature. Accordingly, the natural freshwater biofilm was inferred as one supporting a complete manganese cycle encompassing multiple redox states.

Transcriptome patterns in hidradenitis suppurativa: support for the role of antimicrobial peptides and interferon pathways in disease pathogenesis.

BACKGROUND: Hidradenitis suppurativa (HS) is a recurrent inflammatory disease of the apocrine sweat glands. Immune dysregulation probably contributes to the pathogenesis of HS. AIM: To harness mRNA expression arrays to investigate the transcriptome profile in HS compared with control skin. METHODS: Illumina® HumanHT-12 v4 Expression BeadChips were used to measure mRNA expression in skin samples from HS (n = 10) and abdominoplasty (n = 11) skin specimens. Differentially expressed genes were detected by fitting genewise linear models to the normalized expression data and then modelling using the web-based software Ingenuity® Pathway Analysis. RESULTS: The antimicrobial peptide Dermcidin and the cytokine regulator interleukin (IL)-37 were both significantly downregulated in the HS specimens (Dermcidin expression log ratio -3.93, expression P = 0.04; IL-37 expression log ratio -3.29, expression P < 0.001). Pathway analysis revealed the interferon-signalling pathway, leucocyte extravasation pathway, T helper 1 and 2 pathways and nuclear factor of activated T cells as the top-five upregulated pathways in the HS samples. CONCLUSION: Evaluation of transcriptome patterns in HS compared with normal skin demonstrated downregulation of the antimicrobial peptide Dermcidin and the innate immune regulator IL-37, as well as upregulation of interferon pathways and pathways of leucocyte activation.

Molecular characterization of ß-endoglucanase from antagonistic Trichoderma saturnisporum isolate GITX-Panog (C) induced under mycoparasitic conditions.

The endoglucanase belonging to glycoside hydrolase family 61 are little studied. In present study, a ß-endoglucanase of ~37 kDa induced on autoclaved mycelium of Fusarium oxysporum was cloned and characterized. The molecular characterization of ß-endoglucanase encoding gene revealed presence of a single intron and an open reading frame of 1044-bp which encoded a protein of 347 amino acid residues. The phylogenetic analysis of Eglu revealed its similarity to endo-ß-glucanases of other Trichoderma spp. The catalytic site of ß-endoglucanase contained Asp, Asn, His and Tyr residues. The cDNA encoding ß-glucanase was cloned into E. coli and Pichia pastoris using pQUA-30 and pPIC9K vector system, respectively. The comparison of structure revealed that most similar structure to Eglu is Hypocrea jecorina template 5o2w.1.A of glycoside hydrolase family 61.The biochemical characterization of ß-endoglucanase purified from T. saturnisporum isolate and the recombinant protein expressed in E. coli and P. pastoris was active under acidic conditions with a pH optima of 5 and temperature optima of 60 °C. The purified and expressed enzyme preparation was able to inhibit growth of F.oxysporum at 1 × 105 spores/mL which clearly revealed its significance in plant pathogen suppression.

Phase I study of the novel Cdc2/CDK1 and AKT inhibitor terameprocol in patients with advanced leukemias.

PURPOSE: Inhibiting survivin and Cdc2 (CDK1) has preclinical anti-leukemic activity. Terameprocol is a small molecule survivin and Cdc2/CDK1 inhibitor that was studied in a Phase I dose-escalation trial. PATIENTS AND METHODS: Sixteen patients with advanced acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) were enrolled and 15 treated with Terameprocol in three dose cohorts intravenously three times per week for 2 weeks every 21 days. RESULTS: Patients had AML (n = 11), chronic myelogeneous leukemia in blast phase (CML-BP, n = 2) and one each T-cell acute lymphoblastic leukemia (T-ALL) and MDS. Four, five and six patients were treated at the 1000, 1500 and 2200 mg Terameprocol dose cohorts respectively. Common related treatment emergent adverse events (TEAE) were grade 1 or 2 headache, transaminitis and pruritus, with one grade 4 serious AE (SAE) of pneumonia. No dose limiting toxicity (DLT) was observed, however, due to other observed grade 3 TEAE the recommended phase 2 dose (RP2D) was determined at 1500 mg 3×/week for 2 weeks of a 21-day cycle. Partial remission and transfusion independence in a CML-BP patient (1500 mg cohort) and hematological improvement in erythroid (HI-E) and platelet lineage (HI-P) in an AML patient were observed. Five AML patients had stable disease greater/equal to 2 months. Pharmacodynamic studies showed a reduction of CDK1 and phospho-AKT protein expression. CONCLUSION: Terameprocol can be safely administered to advanced leukemia patients, sufficient drug exposure was obtained and clinical activity and biomarker modulation were observed.

Cross-talk between probiotic lactobacilli and host immune system.

The mechanism by which probiotic lactobacilli affect the immune system is strain specific. As the immune system is a multicompartmental system, each strain has its way to interact with it and induce a visible and quantifiable effect. This review summarizes the interplay existing between the host immune system and probiotic lactobacilli, that is, with emphasis on lactobacilli as a prototype probiotic genus. Several aspects including the bacterial-host cross-talk with the mucosal and systemic immune system are presented, as well as short sections on the competing effect towards pathogenic bacteria and their uses as delivery vehicle for antigens.

Interpersonal difficulties as a risk factor for athletes' eating psychopathology.

The present study sought to determine the predictive role of interpersonal difficulties on eating psychopathology among competitive British athletes (ranging from university to international competition level). A total of 122 athletes (36 males and 86 females) with a mean age of 21.22 years (SD = 4.02), completed a multisection questionnaire that measured eating psychopathology, attachment styles, and quality of relationships with parents, coaches and teammate over a 6-month period. Partial correlations revealed that when controlling for baseline eating psychopathology, only the quality of the relationship with coach and closest teammate were related to athletes' eating psychopathology 6 months later. Subsequent hierarchical multiple regression analyses demonstrated that athletes' eating psychopathology was only predicted by perceived levels of interpersonal conflict with the coach. The current findings provide evidence to suggest that conflict within the coach-athlete relationship is a potential risk factor for eating disorders among athletes and thus it would seem appropriate to raise awareness for its potentially toxic role in athletes' eating psychopathology.

Outcome of partial internal biliary diversion for intractable pruritus in children with cholestatic liver disease.

PURPOSE: Children with cholestatic disorders have undergone liver transplantation for intractable pruritus unresponsive to medical therapy even in the absence of liver failure. Biliary diversion procedures interrupt the entero-hepatic circulation of bile acids allowing them to be excreted in the feces thereby lowering the total bile acid pool. We evaluated the outcome of partial internal biliary diversion (PIBD) in children with intractable pruritus from inherited cholestatic disorders. METHODS: The records of children who underwent PIBD over a 4-year period were reviewed for etiology of liver disease, demographic data, preoperative and postoperative biochemical profile and improvement of pruritus. Standard statistical methods were used for analysis. RESULTS: Of the 12 children, 10 had progressive familial intrahepatic cholestasis (PFIC) and 2 had Alagille syndrome (AS). PIBD was done using an isolated jejunal loop as a conduit from gall bladder to mid ascending colon. Median period of follow up was 30 months. Pruritus resolved in nine children with significant reduction of serum bile acids (P < 0.02). CONCLUSION: To our knowledge, this is the largest reported series of children with PIBD. PIBD is a safe, well-tolerated and effective alternative to liver transplant in children with PFIC and AS who have intractable pruritus in the absence of synthetic liver failure.

Green synthesis, structure-activity relationships, in silico molecular docking, and antifungal activities of novel prenylated chalcones.

A series of 16 novel prenylated chalcones (5A-5P) was synthesized by microwave-assisted green synthesis using 5-prenyloxy-2-hydroxyacetophenone and different benzaldehydes. Comparisons were also performed between the microwave and conventional methods in terms of the reaction times and yields of all compounds, where the reaction times in the microwave and conventional methods were 1-4 min and 12-48 h, respectively. The synthesized compounds were characterized using different spectroscopic techniques, including IR, 1H-NMR, 13C-NMR, and LC-HRMS. The antifungal activities of all compounds were evaluated against Sclerotium rolfsii and Fusarium oxysporum under in vitro conditions and were additionally supported by structure-activity relationship (SAR) and molecular docking studies. Out of the 16 compounds screened, 2'-hydroxy-4-benzyloxy-5'-O-prenylchalcone (5P) showed the highest activity against both S. rolfsii and F. oxysporum, with ED50 of 25.02 and 31.87 mg/L, respectively. The molecular docking studies of the prenylated chalcones within the active sites of the EF1α and RPB2 gene sequences and FoCut5a sequence as the respective receptors for S. rolfsii and F. oxysporum revealed the importance of the compounds, where the binding energies of the docked molecules ranged from -38.3538 to -26.6837 kcal/mol for S. rolfsii and -43.400 to -23.839 kcal/mol for F. oxysporum. Additional docking parameters showed that these compounds formed stable complexes with the protein molecules.

3D Virtual Reality Rehabilitation Therapy for Patients with Vertigo Due to Peripheral Vestibular Dysfunction.

This study aimed to evaluate 3D virtual reality rehabilitation therapy in patients with vertigo due to peripheral vestibular dysfunction. The subjects were 20 patients with peripheral vestibular dysfunction confirmed by Videonystagmography, Divided into 2 groups: Group 1 (study group) underwent vestibular rehabilitation therapy using 3D virtual reality in a customised VR lab with specific headset (Oculus rift and htc vive) with software application, which allows vestibular rehabilitation treatment using high quality immersive virtual reality console in which environment appears real and in 3D. The exercises are designed for gaze stability, increase postural stability, improve vertigo and daily activities, through sensory stimuli and in addition to conventional Cawthorne-Choksey exercises. Group 2 (control group) are treated by conventional Cawthorne-Choksey exercises alone. A VSS-SF (Vertigo Symptom Scale-short form) questionnaire and VAS (Visual Analog Scale) were used to assess the levels of patient satisfaction compared before and after each treatment session in both groups. A significant higher level of subjective satisfaction was observed in patients who underwent 3D virtual reality rehabilitation therapy with conventional therapy (group 1) compared to patients who underwent conventional cawthorne-Choksey exercises alone (group 2). The study gave a substantial subjective satisfaction in patients using 3D virtual reality rehabilitation therapy with conventional therapy (group1) than conventional Cawthorne-Choksey exercises alone (group 2). Future of VR rehabilitation therapy brings a revolutionary novelty in field of rehabilitation therapy were it involves real time stimulation and interaction between sensory, motor and cognitive channels.

Clinical-radiological features and diagnostic modalities for mediastinal melioidosis.

Melioidosis is a potentially life-threatening infection caused by the Gram-negative bacillus Burkholderia pseudomallei. Mediastinal melioidosis has a range of clinical presentations, making it difficult to diagnose: we therefore reviewed the evidence on the clinical characteristics, radiological features and invasive diagnostic modalities or interventions. An electronic search was conducted on three databases (PubMed, SCOPUS, Google Scholar) from November to December 2022. The initial search yielded 120 results, of which 34 studies met the inclusion criteria, but only 31 full-texts were retrievable. Among these, 4 were cohort studies, 26 case reports or series and 1 a conference abstract. The four main themes covered were mediastinal melioidosis as a diagnostic dilemma, unexpected complications, invasive interventions or an accompanying thoracic feature. Radiological manifestations included matting, necrosis and abscess-like collection. Severe presentations of mediastinal melioidosis included superior vena cava obstruction, sinus tract formation and pericardial tamponade. Transbronchial needle aspiration was the most common invasive diagnostic modality. Further research is needed to understand the relationship between the thoracic features of melioidosis on patient prognosis, its relationship to melioidosis transmission and potential preventive measures.

Economic evaluation of the treatment of grade II haemorrhoids: a comparison of stapled haemorrhoidopexy and rubber band ligation.

OBJECTIVES: Haemorrhoidal disease is a common condition causing considerable distress to individuals and significant cost to healthcare services. This paper explored the cost-effectiveness of stapled haemorrhoidopexy (SH) compared with the non-surgical intervention, rubber band ligation (RBL), for grade II symptomatic circumferential haemorrhoids. METHOD: An economic evaluation alongside a randomized controlled trial conducted between October 2002 and February 2005. Adults were recruited and randomized to either SH or RBL. The same surgeon performed all procedures and investigators were blinded until analyses were completed. Primary outcomes measured at 52 weeks were cumulative costs to the NHS, clinical diagnosis of recurrence and quality adjusted life years (QALYs). RESULTS: Sixty symptomatic men and women with confirmed clinical diagnosis of grade II symptomatic haemorrhoids were randomized. Loss to follow-up was up to 10% at 52 weeks. The mean cost for SH was greater than RBL (mean difference: 1483 pounds, 95% CI: 1339-1676); disease recurrence was lower (OR = 0.18, 95% CI: 0.03-0.86); and there was no evidence of a statistically significant difference in QALYs (-0.014, 95% CI: -0.076 to 0.051). SH was associated with a modest incremental cost per recurrence avoided at 12 months follow-up (4945 pounds). Based on current data, it was considered highly unlikely to be cost-effective in terms of incremental cost per QALY. CONCLUSIONS: There is insufficient evidence about the cost-effectiveness of SH for grade II haemorrhoids to recommend its routine use in place of RBL. Further information is needed from larger trials with a longer-term follow-up to inform subsequent economic evaluation.

Randomized controlled trial comparing rubber band ligation with stapled haemorrhoidopexy for Grade II circumferential haemorrhoids: long-term results.

OBJECTIVE: An improved understanding of the pathophysiology of haemorrhoids has resulted in the introduction of new surgical techniques including stapled haemorrhoidopexy (SH). This randomized controlled trial compared the long-term effectiveness of SH with rubber band ligation (RBL) in the treatment of grade II circumferential symptomatic haemorrhoids. METHOD: A consecutive cohort of patients was randomly allocated to either SH or RBL. Data on haemorrhoidal symptoms, Cleveland continence scores, sphincter assessment, SF-36, EQ-5D, HAD score and prior treatment history were assessed at enrollment and reassessed by long-term postal questionnaire. The details were analysed using spss 12.0 from Microsoft Access. RESULTS: Sixty patients were allocated by computer block randomization. Both groups were balanced for age, sex and symptoms. Recurrence favoured SH [3 vs 11; OR 0.18, 95% CI (0.03 to 0.86), P = 0.028] at 1 year and, at a mean of 40.67 (31-47) months [4 vs 12; OR 0.23, 95% CI (0.05, 0.95); P = 0.039]. SH patients experienced prolonged pain [Median (IQR) = 7 (5,7) vs 3 (1,7), P = 0.008] and took a longer time to return to work [6 (3,7) vs 3 (1,6) days, P = 0.018]. This was no significant difference in quality of life. CONCLUSION: Stapled haemorrhoidopexy achieved better disease control at 1 year without any major complication. This was sustained in the long-term. Further studies with greater patient numbers are needed to confirm this study.

Transcriptome Profiling Provides Insights Into Potential Antagonistic Mechanisms Involved in Chaetomium globosum Against Bipolaris sorokiniana.

Chaetomium globosum Kunze is recognized as a potential biocontrol fungus against spot blotch of wheat caused by Bipolaris sorokiniana. Its molecular mechanism of biocontrol activity and the biosynthetic pathways involved have not been yet elucidated. Here, global transcriptome profiling of C. globosum strain Cg2 during interaction with B. sorokiniana isolate BS112 using RNA-seq was performed in order to gain insights into the potential mechanisms of antagonism. The Illumina HiSeq platform (2 × 150 bp) yielded an average of 20-22 million reads with 50-58% GC. De novo assembly generated 45,582 transcripts with 27,957 unigenes. Transcriptome analysis displayed distinct expression profiles in the interaction (Cg2-BS112), out of which 6,109 unique differentially expressed genes were present. The predominant transcripts classified as genes involved in "catalytic activity" constituted 45.06%, of which 10.02% were associated with "hydrolytic activity" (GO:0008152), and similarly, in the biological process, 29.18% of transcripts were involved in "metabolic activity" (GO:0004096 and GO:0006979). Heat map and cluster categorization suggested an increase in the expression levels of genes encoding secondary metabolites like polyketide synthase (GO:0009058), S-hydroxymethyl glutathione dehydrogenase (GO:0006069), terpene cyclase (EC 4.2.3.-), aminotran_1_2 domain-containing protein (GO:0009058), and other hydrolytic CAZYmes such as the glycosyl hydrolase (GH) family (GH 13, GH 2, GH 31, and GH 81; GO:0005975), cellulase domain-containing protein, chitinases, ß-1, 3-glucanases (GO:0004565), glucan endo-1,3-beta-glucanase (GO:0052861), and proteases (GO:0004177). The obtained RNA-seq data were validated by RT-qPCR using 20 randomly chosen genes, showing consistency with the RNA-seq results. The present work is worldwide the first effort to unravel the biocontrol mechanism of C. globosum against B. sorokiniana. It generated a novel dataset for further studies and facilitated improvement of the gene annotation models in the C. globosum draft genome.

Case report of uncontrollable pelvic bleeding--managed by a previously unreported method (QuikClot).

Pelvic haemorrhage can be difficult to control. Several measures including packing, drawing pins, stenting and embolization are available. We present a case where these measures failed to control catastrophic pelvic bleeding while operating in the pelvis to excise a dumbbell tumour involving the right S1 nerve root. Attempted surgical control by a vascular surgeon and radiological control through stenting and embolization failed to control the bleeding. QuikClot is an inert substance and acts as a selective sponge. This product is licensed for external use by the British military. We felt that 'internal' use of Quikclot in this situation might be lifesaving and was applied to the bleeding area, stopping the bleeding immediately.

Diversity and differentiation among fluorescent pseudomonads in crop rhizospheres with whole-cell protein profiles.

Fluorescent pseudomonads from rhizospheres of four different crops, grown under similar soil and climatic conditions were phenotypically characterized to differentiate them into biovars. In protein electrophenogram studies of relationships among fluorescent pseudomonads by UPGMA cluster analysis based on DICE similarity index, the isolates were mainly discerned into three major clusters representing four different biovars. The biovars generally matched the delineated phenotypic clusters with the exception of a strain belonging to biovar II. However, the isolates representing similar rhizospheres and geographic locations were generally distributed into different phenotypic clusters as influenced by factors yet to be determined. The studies reinstated the importance of whole-cell protein analyses in characterizing pseudomonads and assessing their diversity.

Genetic relatedness of Trichoderma isolates antagonistic against Fusarium oxysporum f.sp. dianthi inflicting carnation wilt.

Twenty-eight isolates of Trichoderma belonging to four different species were screened in vitro for their antagonistic ability against Fusarium oxysporum f.sp. dianthi causing carnation wilt. Three different levels of antagonism observed in dual plate assay were further confirmed by cell-free culture filtrate experiments. Isolates showing class I level of antagonism produced maximum lytic enzymes, chitinases and beta-1,3-glucanases. Genetic variability of 25 selected isolates was assessed by random amplified polymorphic DNA technique and the amplified products were correlated for their level of antagonism. Unweighed pair-group method with arithmetical averages cluster analysis revealed prominent inter-and intraspecific genetic variation among the isolates. Based on their genetic relationship, the isolates were mainly distributed into 3 major groups representing T. atroviride, T. pseudokoningii and T. harzianum, with 20-35% interspecific dissimilarity. However, the polymorphism shown by the isolates did not correlate to their level of antagonism.

An innovative way of managing coeliac artery stenosis during pancreaticoduodenectomy.

Coeliac artery stenosis (CAS) is rarely of consequence owing to rich collateral supply from the superior mesenteric artery via the pancreatic head. Pancreaticoduodenectomy (PD) in CAS disrupts these collaterals, and places the liver, stomach and spleen at risk of ischaemia. A 56-year-old man presented with a 3-week history of obstructive jaundice. Computed tomography revealed an operable periampullary tumour with CAS due to compression by the median arcuate ligament with multiple collaterals in the pancreatic head and a prominent gastroduodenal artery (GDA). Following unsuccessful coeliac axis endovascular stenting, a PD was performed. Intraoperative median arcuate ligament release failed to restore good flow in the common hepatic artery (CHA) and splenic artery (SpA) A decision was made to use the left gastric artery (LGA) for arterial reconstruction, disconnect it from the stomach with its origin intact and anastomose it to the supracoeliac aorta. Doppler ultrasonography with a GDA clamp confirmed good filling of the CHA and SpA via the LGA. The GDA was ligated and the PD completed. The patient had an uneventful recovery except for a biochemical pancreatic leak and was discharged on day 10. CAS during PD (confirmed by a decrease in CHA flow with a GDA clamp) requires an additional procedure to restore blood flow to the liver, stomach and spleen. Anastomosing the LGA to the supracoeliac aorta is a simple reconstruction technique for achieving this.

An unreported complication of acute pancreatitis.

Acute pancreatitis constitutes 3% of all admissions with abdominal pain. There are reports of osteal fat necrosis leading to periosteal reactions and osteolytic lesions following severe pancreatitis, particularly in long bones. A 54-year-old man was admitted to our hospital with acute pancreatitis, who later developed spinal discitis secondary to necrotizing pancreatitis. He was treated conservatively with antibiotics and after a month he recovered completely without any neurological deficit. This case is reported for its unusual and unreported spinal complications after acute pancreatitis.

Influence of soil reaction on diversity and antifungal activity of fluorescent pseudomonads in crop rhizospheres.

The diversity and antifungal activity of fluorescent pseudomonads isolated from rhizospheres of tea, gladiolus, carnation and black gram grown in acidic soils with similar texture and climatic conditions were studied. Biochemical characterisation including antibiotic resistance assay, RAPD and PCR-RFLP studies revealed a largely homogenous population. At soil pH (5.2), the isolates exhibited growth with varying levels of siderophore production, irrespective of crop rhizospheres. Two isolates with maximum chitinase production showed antagonism. The bacterial populations in general lacked the ability to produce deleterious traits such as cellulase, pectinase and hydrogen cyanide. However, increased pH levels beyond 5.2 caused reduction in metabolite production with reduced antifungal activity. The homogeneity of the bacterial population irrespective of crop rhizospheres together with decreased secondary metabolite production at higher pH levels reinstated the importance of soil over host plant in influencing rhizosphere populations. The studies also yielded acid tolerant chitinase producing antagonistic fluorescent pseudomonads.