Publications by authors named "Sangeeta Paul"

16 Publications

  • Page 1 of 1

Beneficial Features of Biochar and Arbuscular Mycorrhiza for Improving Spinach Plant Growth, Root Morphological Traits, Physiological Properties, and Soil Enzymatic Activities.

J Fungi (Basel) 2021 Jul 17;7(7). Epub 2021 Jul 17.

Botany Department, Faculty of Science, Suez Canal University, Ismailia 41522, Egypt.

Biochar and arbuscular mycorrhizal fungi (AMF) can promote plant growth, improve soil properties, and maintain microbial activity. The effects of biochar and AMF on plant growth, root morphological traits, physiological properties, and soil enzymatic activities were studied in spinach ( L.). A pot experiment was conducted to evaluate the effect of biochar and AMF on the growth of spinach. Four treatments, a T1 control (soil without biochar), T2 biochar alone, T3 AMF alone, and T4 biochar and AMF together, were arranged in a randomized complete block design with five replications. The biochar alone had a positive effect on the growth of spinach, root morphological traits, physiological properties, and soil enzymatic activities. It significantly increased the plant growth parameters, such as the shoot length, leaf number, leaf length, leaf width, shoot fresh weight, and shoot dry weight. The root morphological traits, plant physiological attributes, and soil enzymatic activities were significantly enhanced with the biochar alone compared with the control. However, the combination of biochar and AMF had a greater impact on the increase in plant growth, root morphological traits, physiological properties, and soil enzymatic activities compared with the other treatments. The results suggested that the combined biochar and AMF led to the highest levels of spinach plant growth, microbial biomass, and soil enzymatic activity.
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http://dx.doi.org/10.3390/jof7070571DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8307178PMC
July 2021

Amelioration of short-term drought stress during different growth stages in Brassica juncea by rhizobacteria mediated maintenance of ROS homeostasis.

Physiol Plant 2021 Aug 18;172(4):1880-1893. Epub 2021 Apr 18.

Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi, India.

In the present investigation, the role of rhizobacteria in alleviating the deleterious effects of drought on mustard was assessed. The plants were exposed to short-term water shortages, during the vegetative and reproductive growth stages. Drought stress in both stages had a negative effect on growth, physiological, and biochemical parameters of mustard. Both the root and shoot biomass were significantly reduced in plants exposed to drought, but rhizobacterial inoculation resulted in better plant biomass than uninoculated plants. The ameliorative effects of inoculation were also indicated by improved relative water content, membrane stability index, total chlorophyll content, and photosynthetic parameters. Similarly, inoculation resulted in enhanced activity of antioxidative enzymes superoxide dismutase (SOD), ascorbate peroxidase, and catalase in both stages of growth which possibly increased stress tolerance by maintaining reactive oxygen species (ROS) homeostasis. There was a significant reduction in the accumulation of H O , proline and total soluble sugar in rhizobacteria treated plants under drought, suggesting that the treated plants did not encounter much stress and could maintain better plant health than uninoculated plants. Expression analysis of the BjP5CSB and BjFeSOD genes was conducted during both the growth stages. Expression of the BjP5CSB gene was significantly down-regulated in inoculated plants under drought, while BjFeSOD gene transcript levels were upregulated. The vegetative stage was more responsive to rhizobacterial inoculations than the reproductive stage under drought. Principal component analysis indicated a differential response by the two growth stages to inoculation. Hence, results indicate that these rhizobacteria reduce the negative impacts of drought in mustard by maintaining ROS homeostasis.
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http://dx.doi.org/10.1111/ppl.13399DOI Listing
August 2021

Comparative response of Spodoptera litura challenged per os with Serratia marcescens strains differing in virulence.

J Invertebr Pathol 2021 07 27;183:107562. Epub 2021 Feb 27.

Department of Biology, Faculty of Science, Jazan University, Jazan, Saudi Arabia.

Host plays an important role in influencing virulence of a pathogen and efficacy of a biopesticide. The present study was aimed to characterize the possible factors present in Spodoptera litura that influenced pathogenecity of orally ingested S. marcescens strains, differing in their virulence. Fifth instar larvae of S. litura responded differently as challenged by two Serratia marcescens strains, SEN (virulent strain, LC 7.02 10 cfu/ml) and ICC-4 (non-virulent strain, LC 1.19 10 cfu/ml). Considerable increase in activity of lytic enzymes protease and phospholipase was recorded in the gut and hemolymph of larvae fed on diet supplemented with S. marcescens strain ICC-4 as compared to the larvae treated with S. marcescens strain SEN. However, a significant up-regulation of antioxidative enzymes SOD (in foregut and midgut), CAT (in the midgut) and GST (in the foregut and hemolymph) was recorded in larvae fed on diet treated with the virulent S. marcescens strain SEN in comparison to larvae fed on diet treated with the non-virulent S. marcescens strain ICC-4. Activity of defense related enzymes lysozyme and phenoloxidase activity were also higher in the hemolymph of larvae fed with diet treated with S. marcescens strain SEN as compared to hemolymph of S. marcescens strain ICC-4 treated larvae. More number of over-expressed proteins was observed in the gut and hemolymph of S. marcescens strains ICC-4 and SEN treated larvae, respectively. Identification of the selected differentially expressed proteins indicated induction of proteins involved in insect innate immune response (Immunoglobulin I-set domain, Apolipophorin III, leucine rich repeat and Titin) in S. marcescens strain SEN treated larvae. Over-expression of two proteins, actin related protein and mt DNA helicase, were noted in S. marcescens treated larvae with very high levels observed in the non-virulent strain. Up-regulation of homeobox protein was noted only in S. marcescens strain ICC-4 challenged larvae. This study indicated that ingestion of non-virulent S. marcescens strain ICC-4 induced strong immune response in insect gut while there was weak response to the virulent S. marcescens strain SEN which probably resulted in difference in their virulence.
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http://dx.doi.org/10.1016/j.jip.2021.107562DOI Listing
July 2021

Genome Assembly of Azotobacter chroococcum Strain W5, a Free-Living Diazotroph Isolated from India.

Microbiol Resour Announc 2020 May 14;9(20). Epub 2020 May 14.

Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi, India.

strain W5 (MTCC 25045) is an effective diazotrophic bacterium with plant growth-promoting traits. Here, we report the draft genome assembly of this biologically and agronomically evaluated strain. The genome assembly in 55 contigs is 4,617,864 bp long, with a G+C content of 66.83%.
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http://dx.doi.org/10.1128/MRA.00259-20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7225537PMC
May 2020

Antioxidant, physiological and biochemical responses of drought susceptible and drought tolerant mustard (Brassica juncea L) genotypes to rhizobacterial inoculation under water deficit stress.

Plant Physiol Biochem 2019 Oct 26;143:19-28. Epub 2019 Aug 26.

Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi, 110 012, India.

Response of drought susceptible (DS) genotype Pusa Karishma LES-39 and drought tolerant (DT) mustard genotype NPJ-124, to rhizobacterial inoculation under water deficit stress, was compared in the present study to determine the influence of inoculants on biochemical and physiological attributes of these two different genotypes. Inoculation was observed to improve root and shoot dry weight in both the genotypes, although better results were observed in the DS genotype. There was variation in the response of the two genotypes to rhizobacterial inoculation, under water deficit stress. Significant improvement in most of the physiological and biochemical parameters including antioxidative enzyme activities of the DS genotype; with concomitant decrease in starch content, accumulation of HO and lipid peroxidation upon inoculation of rhizobacteria was observed. In contrast, there was improvement in only few physiological and biochemical parameters in the DT genotype in response to inoculation with rhizobacteria. There was significant increase in catalase enzyme activity along with concomitant decrease in lipid peroxidation. Thus, drought susceptibility of the mustard genotypes, NPJ-124 and Pusa Karishma LES-39, determined their physiological, biochemical and antioxidative responses to rhizobacterial inoculation under water deficit stress. Expression of drought stress responsive genes belonging to ABA-dependent (RD20 and RD26) and ABA-independent (DREB2 and DREB1-2) pathways was studied in the DS genotype. Expression of DREB2 and DREB1-2 genes was considerably enhanced due to inoculation under water deficit stress; indicating that in Bacillus-mediated priming for drought stress tolerance, in this genotype, ABA-independent pathway probably played key role in enhancing tolerance to drought stress.
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http://dx.doi.org/10.1016/j.plaphy.2019.08.018DOI Listing
October 2019

Diversity and Tissue Preference of Osmotolerant Bacterial Endophytes Associated with Pearl Millet Genotypes Having Differential Drought Susceptibilities.

Microb Ecol 2019 Apr 12;77(3):676-688. Epub 2018 Sep 12.

Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi, 110 012, India.

Genetic and functional diversity of osmotolerant bacterial endophytes colonizing the root, stem, and leaf tissues of pearl millet genotypes differing in their drought susceptibility was assessed. Two genotypes of pearl millet, viz., the drought tolerant genotype TT-1 and the drought susceptible genotype PPMI-69, were used in the present study. Diazotrophs were found to be the predominant colonizers, followed by the Gram positive bacteria in most of the tissues of both the genotypes. Higher proportion of bacterial endophytes obtained from the drought tolerant genotype was found to be osmotolerant. Results of 16S rRNA gene-ARDRA analysis grouped 50 of the highly osmotolerant isolates into 16 clusters, out of which nine clusters had only one isolate each, indicating their uniqueness. One cluster had 21 isolates and remaining clusters were represented by isolates ranging from two to four. The representative isolates from each cluster were identified, and Bacillus was found to be the most prevalent osmotolerant genera with many different species. Other endophytic bacteria belonged to Pseudomonas sp., Stenotrophomonas sp., and Macrococcus caseolyticus. High phylogenetic diversity was observed in the roots of the drought tolerant genotype while different tissues of the drought susceptible genotype showed less diversity. Isolates of Bacillus axarquiensis were present in all the tissues of both the genotypes of pearl millet. However, most of the other endophytic bacteria showed tissue/genotype specificity. With the exception of B. axarquiensis and B. thuringiensis, rest all the species of Bacillus were found colonizing only the drought-tolerant genotype; while M. caseolyticus colonized all the tissues of only the drought susceptible genotype. There was high incidence of IAA producers and low incidence of ACC deaminase producers among the isolates from the root tissues of the drought-tolerant genotype while reverse was the case for the drought-susceptible genotype. Thus, host played an important role in the selection of endophytes based on both phylogenetic and functional traits.
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http://dx.doi.org/10.1007/s00248-018-1257-2DOI Listing
April 2019

Exploitation of microbial antagonists for the control of postharvest diseases of fruits: a review.

Crit Rev Food Sci Nutr 2019 16;59(9):1498-1513. Epub 2018 Jan 16.

a ICAR - Central Institute of Post-Harvest Engineering & Technology , Ludhiana/Abohar , Punjab , India.

Fungal diseases result in significant losses of fruits and vegetables during handling, transportation and storage. At present, post-production fungal spoilage is predominantly controlled by using synthetic fungicides. Under the global climate change scenario and with the need for sustainable agriculture, biological control methods of fungal diseases, using antagonistic microorganisms, are emerging as ecofriendly alternatives to the use of fungicides. The potential of microbial antagonists, isolated from a diversity of natural habitats, for postharvest disease suppression has been investigated. Postharvest biocontrol systems involve tripartite interaction between microbial antagonists, the pathogen and the host, affected by environmental conditions. Several modes for fungistatic activities of microbial antagonists have been suggested, including competition for nutrients and space, mycoparasitism, secretion of antifungal antibiotics and volatile metabolites and induction of host resistance. Postharvest application of microbial antagonists is more successful for efficient disease control in comparison to pre-harvest application. Attempts have also been made to improve the overall efficacy of antagonists by combining them with different physical and chemical substances and methods. Globally, many microbe-based biocontrol products have been developed and registered for commercial use. The present review provides a brief overview on the use of microbial antagonists as postharvest biocontrol agents and summarises information on their isolation, mechanisms of action, application methods, efficacy enhancement, product formulation and commercialisation.
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http://dx.doi.org/10.1080/10408398.2017.1417235DOI Listing
November 2019

Draft Genome Sequence of Strain KMS 55, an Endophytic Diazotroph Isolated from Rice Roots.

Genome Announc 2017 Oct 5;5(40). Epub 2017 Oct 5.

Eurofins Genomics India Private Limited, Bengaluru, Karnataka, India.

strain KMS 55 (MTCC 12703) is an isolate from the root tissues of rice ( L.) that displays a high biological nitrogen fixation ability. Here, we report the complete genome sequence of this strain, which contains 4,637,820 bp, 4,289 protein-coding genes, 5,006 promoter sequences, 62 tRNAs, a single copy of 5S-16S-23S rRNA, and a genome average GC content of 51.18%. Analysis of the ~4.64-Mb genome sequence will give support to increased understanding of the genetic determinants of host range, endophytic colonization behavior, endophytic nitrogen fixation, and other plant-beneficial roles of .
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http://dx.doi.org/10.1128/genomeA.00972-17DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5629048PMC
October 2017

An Environmentally Friendly Engineered Azotobacter Strain That Replaces a Substantial Amount of Urea Fertilizer while Sustaining the Same Wheat Yield.

Appl Environ Microbiol 2017 Aug 17;83(15). Epub 2017 Jul 17.

School of Biotechnology, Jawaharlal Nehru University, New Delhi, India

In our endeavor to improve the nitrogen fixation efficiency of a soil diazotroph that would be unaffected by synthetic nitrogenous fertilizers, we have deleted a part of the negative regulatory gene and constitutively expressed the positive regulatory gene in the chromosome of CBD15, a strain isolated from the local field soil. No antibiotic resistance gene or other foreign gene was present in the chromosome of the engineered strain. Wheat seeds inoculated with this engineered strain, which we have named HKD15, were tested for 3 years in pots and 1 year in the field. The yield of wheat was enhanced by ∼60% due to inoculation of seeds by HKD15 in the absence of any urea application. Ammonium only marginally affected acetylene reduction by the engineered strain. When urea was also applied, the same wheat yield could be sustained by using seeds inoculated with HKD15 and using ∼85 kg less urea (∼40 kg less nitrogen) than the usual ∼257 kg urea (∼120 kg nitrogen) per hectare. Wheat plants arising from the seeds inoculated with the engineered strain exhibited far superior overall performance, had much higher dry weight and nitrogen content, and assimilated molecular N much better. A nitrogen balance experiment also revealed much higher total nitrogen content. Indole-3-acetic acid (IAA) production by the wild type and that by the engineered strain were about the same. Inoculation of the wheat seeds with HKD15 did not adversely affect the microbial population in the field rhizosphere soil. Application of synthetic nitrogenous fertilizers is a standard agricultural practice to augment crop yield. Plants, however, utilize only a fraction of the applied fertilizers, while the unutilized fertilizers cause grave environmental problems. Wild-type soil diazotrophic microorganisms cannot replace synthetic nitrogenous fertilizers, as these reduce atmospheric nitrogen very inefficiently and almost none at all in the presence of added nitrogenous fertilizers. If the nitrogen-fixing ability of soil diazotrophs could be improved and sustained even in the presence of synthetic nitrogenous fertilizers, then a mixture of the bacteria and a reduced quantity of chemical nitrogenous fertilizers could be employed to obtain the same grain yield but at a much-reduced environmental cost. The engineered strain that we have reported here has considerably enhanced nitrogen fixation and excretion abilities and can replace ∼85 kg of urea per hectare but sustain the same wheat yield, if the seeds are inoculated with it before sowing.
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http://dx.doi.org/10.1128/AEM.00590-17DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5514683PMC
August 2017

Characterization of putative virulence factors of Serratia marcescens strain SEN for pathogenesis in Spodoptera litura.

J Invertebr Pathol 2017 02 18;143:115-123. Epub 2016 Dec 18.

Department of Biology, Faculty of Science, Jazan University, Jazan, Saudi Arabia.

Two Serratia marcescens strains, SEN and ICC-4, isolated from diseased insect cadavers were observed to differ considerably in their virulence towards Spodoptera litura. The present study was aimed to characterize the possible virulence factors present in the virulent Serratia marcescens strain SEN. Both the S. marcescens strains were evaluated for the presence of various lytic enzymes such as chitinase, lipase, protease and phospholipase. The virulent S. marcescens strain SEN was observed to possess considerably higher activity of chitinase and protease enzymes; activity of phospholipase enzyme was also higher. Although, all the three toxin genes shlA, phlA and swr could be detected in both the S. marcescens strains, there was a higher expression of these genes in the virulent strain SEN. S. marcescens strain ICC-4 showed greater reduction in overall growth yield in the post-exponential phase in the presence of midgut juice and hemolymph of S. litura larvae, as compared to S. marcescens strain SEN. Proliferation of the S. marcescens strain SEN was also considerably higher in foregut, midgut and hemolymph of S. litura larvae, as compared to strain ICC-4. Peritrophic membrane treated with broth culture of the S. marcescens strain SEN showed higher damage as compared to strain ICC-4. The peritrophic membrane of larvae fed on diet treated with the virulent strain showed considerable damage while the peritrophic membrane of larvae fed on diet treated with the non-virulent strain showed no damage. This is the first report documenting the fate of ingested S. marcescens in S. litura gut and the relative expression of toxin genes from two S. marcescens strains differing in their virulence towards S. litura.
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http://dx.doi.org/10.1016/j.jip.2016.12.004DOI Listing
February 2017

Effect of Nanohexaconazole on Nitrogen Fixing Blue Green Algae and Bacteria.

J Nanosci Nanotechnol 2016 Jan;16(1):643-7

Nanohexaconazole is a highly efficient fungicide against Rhizoctonia solani. Nanoparticles are alleged to adversely affect the non-target organisms. In order to evaluate such concern, the present study was carried out to investigate the effect of nanohexaconazole and its commercial formulation on sensitive nitrogen fixing blue green algae (BGA) and bacteria. Various activities of algae and bacteria namely growth, N-fixation, N-assimilation, Indole acetic acid (IAA) production and phosphate solubilization were differently affected in the presence of hexaconazole. Although, there was stimulatory to slightly inhibitory effect on the growth measurable parameters of the organisms studied at the recommended dose of nanohexaconazole, but its higher dose was inhibitory to all these microorganisms. On the other hand, the recommended as well as higher dose of commercial hexaconazole showed much severe inhibition of growth and metabolic activity of these organisms as compared to the nano preparation. The uses of nanohexazconazole instead of hexaconazole as a fungicide will not only help to control various fungal pathogens but also sustain the growth and activity of these beneficial microorganisms for sustaining soil fertility and productivity.
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http://dx.doi.org/10.1166/jnn.2016.10901DOI Listing
January 2016

Induction of osmoadaptive mechanisms and modulation of cellular physiology help Bacillus licheniformis strain SSA 61 adapt to salt stress.

Curr Microbiol 2015 Apr 6;70(4):610-7. Epub 2015 Jan 6.

Division of Microbiology, Indian Agricultural Research Institute, New Delhi, 10012, India,

Bacillus licheniformis strain SSA 61, originally isolated from Sambhar salt lake, was observed to grow even in the presence of 25 % salt stress. Osmoadaptive mechanisms of this halotolerant B. licheniformis strain SSA 61, for long-term survival and growth under salt stress, were determined. Proline was the preferentially accumulated compatible osmolyte. There was also increased accumulation of antioxidants ascorbic acid and glutathione. Among the different antioxidative enzymes assayed, superoxide dismutase played the most crucial role in defense against salt-induced stress in the organism. Adaptation to stress by the organism involved modulation of cellular physiology at various levels. There was enhanced expression of known proteins playing essential roles in stress adaptation, such as chaperones DnaK and GroEL, and general stress protein YfkM and polynucleotide phosphorylase/polyadenylase. Proteins involved in amino acid biosynthetic pathway, ribosome structure, and peptide elongation were also overexpressed. Salt stress-induced modulation of expression of enzymes involved in carbon metabolism was observed. There was up-regulation of a number of enzymes involved in generation of NADH and NADPH, indicating increased cellular demand for both energy and reducing power.
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http://dx.doi.org/10.1007/s00284-014-0761-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7001579PMC
April 2015

Degradation of sulphonated azo dye Red HE7B by Bacillus sp. and elucidation of degradative pathways.

Curr Microbiol 2014 Aug 30;69(2):183-91. Epub 2014 Mar 30.

Division of Soil Biology, Indian Institute of Soil Science, Bhopal, 462 038, Madhya Pradesh, India.

Bacteria capable of degrading the sulfonated azo dye Red HE7B were isolated from textile mill effluent contaminated soil. The most efficient isolate was identified as Bacillus sp. Azo1 and the isolate could successfully decolorize up to 89% of the dye. The decolorized cultural extract analyzed by HPLC confirmed degradation. Enzymatic analysis showed twofold and fourfold increase in the activity of azoreductase and laccase enzymes, respectively, indicating involvement of both reductive and oxidative enzymes in biodegradation of Red HE7B. Degraded products which were identified by GC/MS analysis included various metabolites like 8-nitroso 1-naphthol, 2-diazonium naphthalene. Mono azo dye intermediate was initially generated from the parent molecule. This mono azo dye was further degraded by the organism, into additional products, depending on the site of cleavage of R-N=N-R molecule. Based on the degradation products identified, three different pathways have been proposed. The mechanism of degradation in two of these pathways is different from that of the previously reported pathway for azo dye degradation. This is the first report of a microbial isolate following multiple pathways for azo dye degradation. Azo dye Red HE7B was observed to be phytotoxic, leading to decrease in root development, shoot length and seedling fresh weight. However, after biotreatment the resulting degradation products were non-phytotoxic.
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http://dx.doi.org/10.1007/s00284-014-0571-2DOI Listing
August 2014

Effects of lindane on lindane-degrading Azotobacter chroococcum; evaluation of toxicity of possible degradation product(s) on plant and insect.

Bull Environ Contam Toxicol 2013 Mar 22;90(3):351-6. Epub 2012 Dec 22.

Division of Microbiology, Indian Agricultural Research Institute, New Delhi, 110012, India.

The effects of lindane on growth and plant growth-promoting traits of two lindane-degrading Azotobacter chroococcum strains (JL 15 and JL 104) were determined. The potential of both A. chroococcum strains to degrade lindane was also determined. Lower concentrations of lindane had a stimulatory effect, and higher concentrations generally had an inhibitory effect on growth and plant growth-promoting activities. A high percentage (>90%) of lindane was degraded by both strains at a lindane concentration of 10 ppm. Lindane at 1,000 ppm decreased seed germination and reduced seedling fresh weight. However, the possible degradation products for a starting lindane concentration of 10 ppm was found to be non-phytotoxic. Toxicity studies with larvae of Spilarctia obliqua resulted in an LC50 estimate of 3.41 ppm for lindane solutions into which leaf discs were dipped. No toxicity was observed for possible degradation products.
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http://dx.doi.org/10.1007/s00128-012-0930-2DOI Listing
March 2013

Physiological studies on endorhizospheric establishment of Azotobacter chroococcum in wheat.

J Basic Microbiol 2010 Jun;50(3):266-73

Department of Biological Sciences, Texas Tech University, Lubbock, Texas, USA.

Ten strains of Azotobacter chroococcum were studied for their ability to invade the endorhizosphere of wheat. Strain W-5 exhibited ability to invade endorhizosphere as shown in the microscopic observations. This strain was compared with the strain OA-3 which did not invade the endorhizosphere zone. Strain W-5 showed higher production of cellulase and pectinase than OA-3. Both the strains induced defense enzymes in the host plant. However, induction of peroxidase and phenylalanine ammonia lyase activities (PAL) was higher in OA-3 than W-5. Quantitative differences in flavonoid like compounds obtained from root extracts and root exudates of plants inoculated with these strains were observed.
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http://dx.doi.org/10.1002/jobm.200900218DOI Listing
June 2010

Ex situ and in situ biodegradation of lindane by Azotobacter chroococcum.

J Environ Sci Health B 2010 Jan;45(1):58-66

Division of Microbiology, Indian Agricultural Research Institute, New Delhi, India.

This study was undertaken to investigate the potential of Azotobacter chroococcum for degrading lindane. Ten cultures were screened for lindane degradation by a chloride estimation method and the best A. chroococcum culture JL 102 was selected for further studies. This strain was subjected to a lindane-tolerance experiment and based on the results obtained, 10 and 100 ppm of lindane were selected to study the potential of the A. chroococcum strain for ex situ and in situ biodegradation of lindane. The organism was grown in 2 different media viz. Jensen's broth and soil extract broth and ex situ lindane degradation was studied for a period of 6 days. Maximum degradation of lindane was recorded at 10 ppm concentration. The degradation was higher in Jensen's medium, compared to the soil extract broth. A pot culture experiment was conducted using both sterile and non-sterile soils supplemented with 10 ppm lindane to study in situ degradation potential of this strain for a period of 8 weeks. In both the conditions (sterile and non-sterile), the organism exhibited increased degradation over the days with maximum degradation observed on the 8th week of incubation. It could degrade most of the applied lindane by the end of the study period.
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http://dx.doi.org/10.1080/03601230903404465DOI Listing
January 2010
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