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Peter B Van Berkum
Soybean Genomics & Improvement Laboratory
Microbiologist

Phone: (301) 504-7280
Fax: (301) 713-0308

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Publications (Clicking on the reprint icon Reprint Icon will take you to the publication reprint.)
Stemphylium leaf spot of parsley in California caused by Stemphylium vesicarium - (Peer Reviewed Journal)
Koike, S.B., Oneill, N.R., Van Berkum, P.B., Wolf, J.E., Daugovish, O. 2013. Stemphylium leaf spot of parsley in California caused by Stemphylium vesicarium. Plant Disease. 97:315-322.
Development and application of a multilocus sequence analysis method for the identification of genotypes within genus Bradyrhizobium and for establishing nodule occupancy of soybean (Glycine max L. Merr) - (Peer Reviewed Journal)
Van Berkum, P.B., Elia, P.E., Song, Q., Eardly, B. 2012. Development and application of a multilocus sequence analysis method for the identification of genotypes within genus Bradyrhizobium and for establishing nodule occupancy of soybean (Glycine max L. Merr). Molecular Plant-Microbe Interactions. 25(3):321-330.
Sinorhizobium meliloti strains TII7 and A5 by Multilocus Sequence Typing (MLST) have chromsomes identical with Rm1021 and form an effective and ineffective symbiosis with Medicago truncatula line Jemalong A17, respectively - (Peer Reviewed Journal)
Zribi, K., Mhadhbi, H., Badri, Y., Aouani, M.E., Van Berkum, P.B. 2011. Sinorhizobium meliloti strains TII7 and A5 by Multilocus Sequence Typing (MLST) have chromsomes identical with Rm1021 and form an effective and ineffective symbiosis with Medicago truncatula line Jemalong A17, respectively. Canadian Journal of Microbiology. 59:996-1002.
Evidence for an American origin of the genes for symbiosis in R. lusitanum - (Peer Reviewed Journal)
Valverde, A., Velazquez, E., Cervantes, E., Igual, J.M., Van Berkum, P.B. 2011. Evidence for an American origin of the genes for symbiosis in R. lusitanum. Applied and Environmental Microbiology. 77(16):5665-5670.
Ensifer, Phyllobacterium and Rhizobium species occupy nodules of Medicago sativa (alfalfa) and Melilotus alba (sweet clover) grown at a Canadian site without a history of cultivation - (Peer Reviewed Journal)
Bromfield, E.S., Tambong, J.T., Cloutier, S., Prevost, D., Lagurerre, G., Van Berkum, P.B., Tran Thi, T.V., Assabgui, R., Barran, L.R. 2010. Ensifer, Phyllobacterium and Rhizobium species occupy nodules of Medicago sativa (alfalfa) and Melilotus alba (sweet clover) grown at a Canadian site without a history of cultivation. Microbiology. 156:505-520.
Application of Multilocus Sequence Typing To Study the Genetic Structure of Megaplasmids in Medicago-Nodulating Rhizobia - (Peer Reviewed Journal)
Van Berkum, P.B., Elia, P.E., Eardly, B.D. 2010. Application of Multilocus Sequence Typing To Study the Genetic Structure of Megaplasmids in Medicago-Nodulating Rhizobia. Applied and Environmental Microbiology. 76:3967-3977.
Characterization of Ni-resistant bacteria in the rhizosphere of the hyperaccumulator alyssum murale by 16S RRNA gene sequence analysis - (Peer Reviewed Journal)
Abou-Shanab, R.I., Van Berkum, P.B., Angle, J.S., Delorme, T.A., Chaney, R.L., Ghozlan, H.A., Ghanem, K., Moawad, H. 2010. Characterization of Ni-resistant bacteria in the rhizosphere of the hyperaccumulator alyssum murale by 16S RRNA gene sequence analysis. World Journal of Microbiology and Biotechnology. 26(1):101-108.
Rhizobia from Lanzarote, the Canary Islands, that nodulate Phaseolus vulgaris have characteristics in common with LMW RNA group II Sinorhizobium meliloti of Medicago, Melilotus and Trigonella from soils of mainland Spain - (Peer Reviewed Journal)
Zurdo-Pineiro, J.L., Garcia-Fraile, P., Rivas, R., Leon-Barrios, M., Willems, A., Mateos, P.F., Martinez-Molina, E., Velazquez, E., Van Berkum, P.B. 2009. Rhizobia from Lanzarote, the Canary Islands, that nodulate Phaseolus vulgaris have characteristics in common with LMW RNA group II Sinorhizobium meliloti of Medicago, Melilotus and Trigonella from soils of mainland Spain. Applied and Environmental Microbiology. 75:2354-2359.
Rhizobia from Lanzarote, the Canary Islands, that nodulate Phaseolus vulgars have characteristics in common with Sinorhizobium meliloti isolates from mainland Spain - (Peer Reviewed Journal)
Van Berkum, P.B., Elia, P.E., Peix, A., Garcia-Fraile, P., Leon-Barrios, M., Velazquez, E. 2009. Rhizobia from Lanzarote, the Canary Islands, that nodulate Phaseolus vulgars have characteristics in common with Sinorhizobium meliloti isolates from mainland Spain. Applied and Environmental Microbiology. 75(8):2354-2359.
Evidence from ITS sequence analysis of 31 and 110 serogroup soybean strains that extant members of the genus Bradyrhizobium are likely the products of reticulate evolutionary events - (Peer Reviewed Journal)
Van Berkum, P.B., Fuhrmann, J.J. 2009. Evidence from ITS sequence analysis of 31 and 110 serogroup soybean strains that extant members of the genus Bradyrhizobium are likely the products of reticulate evolutionary events. Applied and Environmental Microbiology. 75:78-82.
Two different stable low molecular weight RNA (LMW RNA) profiles within Sinorhizobium meliloti and within Sinorhizobium medicae - (Peer Reviewed Journal)
Del Villar, M., Rivas, R., Peix, A., Mateos, P.F., Martinez-Molina, E., Van Berkum, P.B., Willems, A., Velazquez, E. 2008. Two different stable low molecular weight RNA (LMW RNA) profiles within Sinorhizobium meliloti and within Sinorhizobium medicae. FEMS Microbiology Letters. 282:273-281.
Medicago ciliaris growing in Tunisian soils is preferentially nodulated by Sinorhizobium medicae - (Peer Reviewed Journal)
Zribi, K., Badri, Y., Van Berkum, P.B., Aouani, M.E. 2007. Medicago ciliaris growing in Tunisian soils is preferentially nodulated by Sinorhizobium medicae. Australian Journal of Soil Science. 45:473-477.
Chromosomal and symbiotic relationships of rhizobia nodulating Medicago truncatula and M. laciniata. - (Peer Reviewed Journal)
Van Berkum, P.B., Badri, Y., Elia, P.E., Aouani, M.E., Eardly, B.D. 2007. Chromosomal and symbiotic relationships of rhizobia nodulating Medicago truncatula and M. laciniata. Applied and Environmental Microbiology. 73(23)7597-7604.
The genetic diversity of rhizobia associated with Dalea purpurea Vent. in fragmented grasslands of West-Central Minnesota. - (Peer Reviewed Journal)
Martir, M., Tlusty, B., Van Berkum, P.B., Graham, P.H. 2007. The genetic diversity of rhizobia associated with Dalea purpurea Vent. in fragmented grasslands of West-Central Minnesota. Canadian Journal of Microbiology. 53:351-363.
HEAVY METAL RESISTANCE AND GENOTYPIC ANALYSIS OF METAL RESISTANCE GENES IN GRAM-POSITIVE AND GRAM-NEGATIVE BACTERIA PRESENT IN SERPENTINE SOIL AND IN THE RHIZOSPHERE OF ALYSSUM MURALE. - (Peer Reviewed Journal)
Van Berkum, P.B., Abou-Shanab, R.A., Angle, J.S. 2007. Heavy metal resistance and genotypic analysis of metal resistance genes in gram-positive and gram-negative bacteria present in serpentine soil and in the rhizosphere of alyssum murale. Chemosphere. v. 68, p. 360-367.
CHROMATE-TOLERANT BACTERIA FOR ENHANCED METAL UPTAKE BY EICHHORNIA CRASSIPES (MART.) - (Peer Reviewed Journal)
Van Berkum, P.B., Abou-Shanab, R.I., Angle, J.S. 2007. Chromate-tolerant bacteria for enhanced metal uptake by eichhornia crassipes (mart.). International Journal of Phytoremediation. v. 9. p.91-105.
COMPARISON OF RHIZOBIA THAT NODULATE MEDICAGO LACINIATA AND M. TRUNCATULA PRESENT IN A SINGLE TUNISIAN ARID SOIL. - (Peer Reviewed Journal)
Van Berkum, P.B., Badri, Y., Zribi, K., Badri, M., Aouani, M.E., Huguet, T. 2007. Comparison of rhizobia that nodulate medicago laciniata and m. truncatula present in a single tunisian arid soil. Canadian Journal of Microbiology. 53:277-283.
MOLECULAR DNA MARKERS UTILIZED TO DISCERN ALFALFA FALL DORMANCY CHECK CULTIVARS - (Abstract Only)
Bauchan, G.R., Xia, Z., Van Berkum, P.B. 2006. Molecular dna markers utilized to discern alfalfa fall dormancy check cultivars. North American Alfalfa Improvement Conference. July 16-19, 2006, Minneapolis, MN. p.6.
RHIZOBIUM GIARDINII IS THE MICROSYMBIONT OF ILLINOIS BUNDLEFLOWER (DESMANTHUS ILLINOENSIS (MICHX) MACMILLAN IN MIDWESTERN PRAIRIES. - (Peer Reviewed Journal)
Van Berkum, P.B., Beyhaut, E., Tlusty, B., Graham, P.H. 2006. Rhizobium giardinii is the microsymbiont of illinois bundleflower (desmanthus illinoensis (michx) macmillan in midwestern prairies. Canadian Journal of Microbiology. 52:903-907.
MULTI-LOCUS SEQUENCE TYPING (MLST), A BASIS FOR THE POPULATION ANALYSIS OF MEDICAGO-NODULATING RHIZOBIA. - (Peer Reviewed Journal)
Van Berkum, P.B., Elia, P.E., Eardly, B.D. 2006. Multi-locus sequence typing (mlst), a basis for the population analysis of medicago-nodulating rhizobia. Journal of Bacteriology. 188:5570-5577.
PROPOSAL FOR COMBINING BRADYRHIZOBIUM SPP. (AESCHYNOMENE INDICA) WITH BLASTOBACTER DENITRIFICANS AND TO TRANSFER BLASTOBACTER DENITRIFICANS (HIRSH AND MULLER 1985) TO THE GENUS BRADYRHIZOBIUM AS BRADYRHIZOBIUM DENITRIFICANS - (Peer Reviewed Journal)
Van Berkum, P.B., Eardly, B.D., Leibold, J.M. 2006. Proposal for combining bradyrhizobium spp. (aeschynomene indica) with blastobacter denitrificans and to transfer blastobacter denitrificans (hirsh and muller 1985) to the genus bradyrhizobium as bradyrhizobium denitrificans. Systematic and Applied Microbiology 29:207-213.
IMPACT OF GENOMICS ON THE RECONSTRUCTION OF EVOLUTIONARY RELATIONSHIPS OF NITROGEN-FIXING BACTERIA AND IMPLICATIONS FOR TAXONOMY - (Book / Chapter)
Van Berkum, P.B., Eardly, B.D. 2005. Impact of genomics on the reconstruction of evolutionary relationships of nitrogen-fixing bacteria and implications for taxonomy. Nitrogen Fixation International Congress. Chapter 13, p. 201-219.
CHARACTERISTICS OF RHIZOBIA ASSOCIATED WITH DALEA SPP. IN THREE PRAIRIE AREAS OF MINNESOTA. - (Peer Reviewed Journal)
Van Berkum, P.B., Tlusty, B., Grahma, P.H. 2004. Characteristics of rhizobia associated with dalea spp. in three prairie areas of minnesota.. Canadian Journal of Microbiology 51:15-23.
USE OF POPULATION GENETIC STRUCTURE TO DEFINE SPECIES LIMITS IN THE RHIZOBIACEAE - (Peer Reviewed Journal)
Van Berkum, P.B., Eardly, B. 2004. Use of population genetic structure to define species limits in the rhizobiaceae. Symbiosis 38: 109-122.
CHARACTERISTICS OF RHIZOBIA NODULATING BEANS IN THE CENTRAL REGION OF MINNESOTA. - (Peer Reviewed Journal)
Van Berkum, P.B., Bernal, G.R., Tlusty, B., Esteves De Jensen, C., Graham, P.H. 2004. Characteristics of rhizobia nodulating beans in the central region of minnesota. Canadian Journal of Microbiology 50:1023-1031.
GENOMES, RIBOSOMAL GENES AND EVOLUTINARY BIOLOGY OF RHIZOBIA - (Abstract Only)
Van Berkum, P.B., Eardly, B.B. 2004. Genomes, ribosomal genes and evolutinary biology of rhizobia [abstract]. North American Conference on Symbiotic Nitrogen Fixation.Program and Abstracts. P.19.
RHIZOBIAL 16S AND DNAK GENES: MOSAICISM AND THE UNCERTAIN PHYLOGENETIC PLACEMENT OF RHIZOBIUM GALEGAE - (Peer Reviewed Journal)
Van Berkum, P.B., Eardly, B.D., Nour, S.M., Selander, R.K. 2004. Rhizobial 16s and dnak genes: mosaicism and the uncertain phylogenetic placement of rhizobium galegae [abstract]. North American Conference on Symbiotic Nitrogen Fixation. p. 73.
ETHIOPIAN SOILS HARBOR NATURAL POPULATIONS OF RHIZOBIA THAT FORM SYMBIOSES WITH COMMON BEAN (PHASEOLUS VULGARIS L.). - (Peer Reviewed Journal)
Van Berkum, P.B., Beyene, D., Kassa, S., Asseffa, A., Gebremedhin, T. 2003. Ethiopian soils harbor natural populations of rhizobia that form symbioses with common bean (Phaseolus Vulgaris L.).. Archives for Microbiology. 181(2): 129-136.
BIOCONTROL GENOTYPES OF FUSARIUM OXYSPORUM FROM TOMATO FIELDS IN FLORIDA - (Peer Reviewed Journal)
Bao, J., Fravel, D. R., Lazarovits, G., Chellemi, D., van Berkum, P., and O¿Neill, N. 2004. Biocontrol genotypes of Fusarium oxysporum from tomato fields in Florida. Phytoparasitica 32:9-20.
PHENOTYPIC AND GENETIC DIVERSITY OF RHIZOBIA ISOLATED FROM NODULES OF CLOVER GROWN IN A ZINC AND CADMIUM CONTAMINATED SOIL - (Peer Reviewed Journal)
Delorme, T.A., Gagliardi, J.V., Angle, J.S., Van Berkum, P.B., Chaney, R.L. 2003. Phenotypic and genetic diversity of rhizobia isolated from nodules of clover grown in a zinc and cadmium contaminated soil. Soil Science Society of America Journal. 67(6):1746-1754.
SOIL MICROBIAL EFFECTS ON HEAVY METAL UPTAKE INTO HYPERACCUMULATORS - (Abstract Only)
MESORHIZOBIUM AMORPHASE, A RHIZOBIAL SPECIES THAT NODULATES AMORPHA FRUTICOSA, IS NATIVE TO AMERICAN SOILS. - (Peer Reviewed Journal)
CONFLICTING PHYLOGEOGRAPHIC PATTERNS IN RRNA AND NIFD INDICATE REGIONALLY RESTRICTED GENE TRANSFER IN BRADYRHIZOBIUM - (Peer Reviewed Journal)
GENETIC ANALYSIS OF PATHOGENIC AND NONPATHOGENIC FUSARIUM OXYSPORUM FROM TOMATO PLANTS USING VCG, RDNA ITS SEQUENCE AND AFLP - (Peer Reviewed Journal)
LEPTOSPHAERIA AND PHAEOSPHAERIA MOLECULAR SYSTEMATICS - (Peer Reviewed Journal)
INFLUENCE OF BIOSOLIDS COMPOST ON THE BRADYRHIZOBIAL GENOTYPES RECOVERED FROM COWPEA AND SOYBEAN NODULES. - (Peer Reviewed Journal)
THE AQUATIC BUDDING BACTERIUM BLASTOBACTER DENITRIFICANS IS A NITROGEN- FIXING SYMBIONT OF AESCHYNOMENE INDICA. - (Peer Reviewed Journal)
THE PUTATIVE GLUTAMATE RECEPTORS FROM PLANTS ARE RELATED TO TWO SUPER FAMILIES OF ANIMAL NEUROTRANSMITTER RECEPTORS VIA DISTINCT EVOLUTIONARY MECHANISMS. - (Peer Reviewed Journal)
SYSTEMATICS OF PARAPHAEOSPHAERIA: A MOLECULAR AND MORPHOLOGICAL APPROACH - (Peer Reviewed Journal)
MOLECULAR PHYLOGENY OF STEMPHYLIUM SPP BASED ON ITS AND GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE GENE SEQUENCES - (Peer Reviewed Journal)
DIVERSITY OF RHIZOBIA IN A CD AND ZN ENRICHED SOIL - (Abstract Only)
POPULATION STRUCTURE OF FUSARIUM OXYSPORUM IN TOMATO PRODUCTION IN FLORIDA - (Abstract Only)
A UNIQUE MYCOBACTERIUM SP. RESEMBLING MYCOBACTERIUM MARINUM AND MYCOBACTERIUM ULCERANS ISOLATED FROM STRIPED BASS (MORONE SAXATILIS) - (Peer Reviewed Journal)
POPULATION STRUCTURE OF FUSARIUM OXYFPORUM IN CONVENTIONAL AND ORGANIC TOMATO PRODUCTION IN FLORIDA - (Abstract Only)
MOLECULAR PHYLOGENY OF STEMPHYLIUM SPP., PATHOGENS OF ALFALFA AND OTHER LEGUMES - (Abstract Only)
CHARACTERIZATION OF RHIZOBIAL ISOLATES OF PHASEOLUS VULGARIS BY STAIRCASE ELECTROPHORESIS OF LOW MOLECULAR WEIGH RNA. - (Peer Reviewed Journal)
CHARACTERIZATION OF SOYBEAN BRADYRHIZOBIA FOR WHICH SEROGROUP AFFINITIES HAVE NOT IDENTIFIED. - (Peer Reviewed Journal)
A CRITICAL EXAMINATION OF 16S RRNA GENE SEQUENCE DIVERGENCE FOR THE RECONSTRUCTION OF BACTERIAL EVOLUTIONARY HISTORIES: THE RHIZOBIACEAE. - (Abstract Only)
CHARACTERIZATION OF SOYBEAN BRADYRHIZOBIA FOR WHICH SEROGROUP AFFINITIES HAVE NOT BEEN IDENTIFIED. - (Abstract Only)
POPULATION STRUCTURE OF FUSARIUM OXYSPORUM IN CONVENTIONAL AND ORGANIC TOMATO PRODUCTION IN FLORIDA - (Abstract Only)
OPHIOSPHAERELLA AGROSTIS SP. NOV. AND ITS RELATIONSHIP TO OTHER SPECIES OF OPHIOSPAERELLA. - (Peer Reviewed Journal)
EVOLUTIONARY RELATIONSHIPS AMONG THE SOYBEAN BRADYRHIZOBIA RECONSTRUCTED FROM 16S RRNA AND INTERNALLY TRANSCRIBED SPACER SEQUENCE DIVERGENCE. - (Peer Reviewed Journal)
DISCRIMINATION BETWEEN TWO PERKENSIS SPP. ISOLATED FROM THE SOFTSHELL CLAM,MYA ARENARIA, BY SEQUENCE ANALYSIS OF TWO INTERNAL TRANSCRIBED SPACER REGIONS AND THE 5.8S RIBOSOMAL RNA GENE. - (Peer Reviewed Journal)
OPHIOSPHAERELLA AGROSTIS, A NEW SPP. CAUSING A DISEASE OF AGROSTIS PALUSTRIS. - (Abstract Only)
PHYLOGENY OF RHIZOBIA - (Proceedings)
THE PHYLOGENY OF RHIZOBIACEAE - (Abstract Only)
A SINORHIZOBIUM FREDII STRAIN ENHANCED GROWTH AND PRODUCTIVITY OF FUNGICIDE-TREATED SOYBEAN. - (Abstract Only)
SYMBIOTIC COMPETENCE OF RHIZOBIUM LEGUMINOSARUM ON DIVERSE GENOTYPES OF FABA BEAN. - (Abstract Only)
DIVERSITY OF RHIZOBIA ASSOCIATED WITH AMORPHA FRUTICOSA ISOLATED FROM CHINESE SOILS AND DESCRIPTION OF MESORHIZOBIUM AMORPHAE SP. NOV. - (Peer Reviewed Journal)
CHARACTERIZATION OF TWO PERKINSUS SPP. FROM THE SOFTSHELL CLAM, MYA AREARIAUSING THE SMALL SUBUNIT RIBOSOMAL RNA GENES. - (Peer Reviewed Journal)
MORPHOLOGICAL AND MOLECULAR STUDIES ON DENDRYPHION PENICILLATUM AND PLEOSPORA PAPAVERACEA, PATHOGENS OF PAPAVER SOMNIFERUM - (Peer Reviewed Journal)
GENETIC DIVERSITY AMONG RHIZOBIA ISOLATED FROM SOILS OF THE AMERICAS - (Abstract Only)
IDENTIFICATION OF BRADYRHIZOBIA IN SOYBEAN INOCULANTS BY RAPD ANALYSIS - (Abstract Only)
GENETIC ANALYSIS OF RHIZOBIA OF MEDICAGO AND GLYCINE - (Abstract Only)
SOME ISSUES OF RELEVANCE IN THE TAXONOMY OF RHIZOBIA - (Proceedings)
RHIZOBIUM HUAUTLENSE SP. NOV., A SYMBIONT OF SESBANIA HERBACEA WHICH HAS CLOSE PHYLOGENETIC RELATIONSHIP WITH RHIZOBIUM GALGAE - (Peer Reviewed Journal)
AFLP CHARACTERIZATION OF COLLETOTRICHUM ISOLATES PATHOGENIC TO ALFALFA - (Abstract Only)
GENETIC DIVERSITY OF RHIZOBIA ISOLATED FROM ASTRAGALUS, OXYTROPIS, AND ONOBRYCHIS SPP. - (Abstract Only)
APPLICATION OF AMPLIFIED FRAGMENT LENGTH POLYMORPHISM (AFLP) FOR GENETIC CHARACTERIZATION OF COLLETOTRICHUM PATHOGENS OF ALFALFA (MEDICAGO SATIVA) - (Peer Reviewed Journal)
DISTRIBUTION OF GENES OF A CYTOCHROME P450 OPERON AMONG THE RHIZOBIACEAE - (Peer Reviewed Journal)
RHIZOBIUM MONGOLENSE SP. NOV., IS ONE OF THREE RHIZOBIAL GENOTYPES IDENTIFIED WHICH NODULATE AND FORM NITROGEN-FIXING SYMBIOSES WITH MEDICAGO RUTHENICA (L.) LEDEBOUR - (Peer Reviewed Journal)
GENETIC DIVERSITY OF BRADYRHIZOBIA NODULATING LUPINUS SPP. - (Peer Reviewed Journal)
TRANSFER OF RHIZOBIUM LOTI, RHIZOBIUM HUAKUII, RHIZOBIUM CICERI, RHIZOBIUM MEDITERRANEUM, AND RHIZOBIUM TIANSHANENESE TO MESORHIZOBIUM GEN. NOV. - (Peer Reviewed Journal)
DIFFERENTIATION OF CLOVER RHIZOBIUM ISOLATED FROM BIOSOLIDS-AMENDED AND CONTROL SOILS WITH VARYING PH - (Peer Reviewed Journal)
FOUR UNNAMED SPECIES OF NONSYMBIOTIC RHIZOBIA ISOLATED FROM THE RHIZOSPHERE OF LOTUS CORNICULATUS - (Peer Reviewed Journal)
RHIZOBIA ISOLATED FROM ASTRAGALUS, OXYTROPIS AND ONOBRYCHIS SPP.: ESTIMATEDPHYLOGENY BY ANALYSIS OF MAPPED RESTRICTION SITE POLYMORPHISM (MRSP) WITHIN16S RRNA GENES/DETERMINATION OF GENOMIC DIVERSITY BY PCR DNA FINGERPRINTING - (Peer Reviewed Journal)
MOLECULAR EVOLUTIONARY SYSTEMATICS OF THE RHIZOBIACEAE - (Book / Chapter)