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. 2000 Nov;66(11):4785-9.
doi: 10.1128/AEM.66.11.4785-4789.2000.

Genetic diversity and dynamics of Sinorhizobium meliloti populations nodulating different alfalfa cultivars in Italian soils

M Carelli  1 , S Gnocchi, S Fancelli, A Mengoni, D Paffetti, C Scotti, M Bazzicalupo
Affiliations

Genetic diversity and dynamics of Sinorhizobium meliloti populations nodulating different alfalfa cultivars in Italian soils

M Carelli et al. Appl Environ Microbiol. 2000 Nov.

Abstract

We analyzed the genetic diversity of 531 Sinorhizobium meliloti strains isolated from nodules of Medicago sativa cultivars in two different Italian soils during 4 years of plant growth. The isolates were analyzed for DNA polymorphism with the random amplified polymorphic DNA method. The populations showed a high level of genetic polymorphism distributed throughout all the isolates, with 440 different haplotypes. Analysis of molecular variance allowed us to relate the genetic structure of the symbiotic population to various factors, including soil type, alfalfa cultivar, individual plants within a cultivar, and time. Some of these factors significantly affected the genetic structure of the population, and their relative influence changed with time. At the beginning of the experiment, the soil of origin and, even more, the cultivar significantly influenced the distribution of genetic variability of S. meliloti. After 3 years, the rhizobium population was altered; it showed a genetic structure based mainly on differences among plants, while the effects of soil and cultivar were not significant.

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Figures

FIG. 1
FIG. 1
Unweighted pair group with mathematical average dendrograms of S. meliloti strains isolated from clay soil in 1994 (A) and 1997 (B). L, cultivar Lodi; O, cultivar Oneida. Each letter indicates a different isolate.
FIG. 2
FIG. 2
Among-plant variance components in each soil-cultivar combination for the 1994, 1995, and 1997 samples. Percentages of total variance were computed by AMOVA. SL, sandy loam soil; C, clay soil.
See this image and copyright information in PMC

References

    1. Bromfield E S P, Shina I B, Wolynetz M S. Influence of location, host cultivar, and inoculation on the composition of naturalized populations of Rhizobium meliloti in Medicago sativa nodules. Appl Environ Microbiol. 1986;51:1077–1084. - PMC - PubMed
    1. Demezas D H, Reardon T B, Watson J M, Gibson A H. Genetic diversity among Rhizobium leguminosarum bv. trifolii strains revealed by allozymes and restriction fragment length polymorphism analyses. Appl Environ Microbiol. 1991;57:3489–3495. - PMC - PubMed
    1. Excoffier L, Smouse P E, Quattro J M. Analysis of molecular variance inferred from metric distance among DNA haplotypes: application to human mitochondrial DNA restriction data. Genetics. 1992;131:479–491. - PMC - PubMed
    1. Laguerre G, Mavingui P, Allard M R, Charnay M P, Louvrier P, Mazurier S I, Rigottier-Gois L, Amarger N. Typing of rhizobia by PCR DNA fingerprinting and PCR-restriction fragment length polymorphism analysis of chromosomal and symbiotic gene regions: application to Rhizobium leguminosarum and its different biovars. Appl Environ Microbiol. 1996;62:2029–2036. - PMC - PubMed
    1. Leung K, Strain S R, de Bruijn F J, Bottomley P J. Genotypic and phenotypic comparisons of chromosomal types within an indigenous soil population of Rhizobium leguminosarum bv. trifolii. Appl Environ Microbiol. 1994;60:416–426. - PMC - PubMed

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