Location of Repository

Evolution and ecology of the Ceanothus-Frankia symbiosis

By 

Abstract

Graduation date: 1998The evolutionary relationship between Frankia and actinorhizal plants was evaluated\ud by reconstructing molecular phylogenetic trees from nifH, 16S rDNA, and rbcL\ud nucleotide sequences. Subgroupings in Frankia phylogenetic trees reconstructed from\ud nifH and from 16S rDNA sequences were consistent in terms of plant origins of Frankia\ud strains. Although the branching order of Frankia 16S rDNA and plant rbcL trees were\ud different, subgroupings of Frankia and of plants correlated well in terms of symbiotic\ud partnership. Tree matching, estimated divergence times, and molecular clock hypothesis\ud tests indicated that Frankia clades diverged more recently than plant clades and that\ud actinorhizal symbioses originated more than three times after the plant clades diverged.\ud A phylogenetic tree of Ceanothus species, which are symbiotic partners of Frankia,\ud was reconstructed using ndhF gene sequences. The analysis identified two main clades\ud corresponding to two subgenera: Ceanothus and Cerastes. The analysis also suggested\ud that three monophyletic clades within the subgenus ceanothus can be delimited on the\ud basis of vegetative characters. Based on rbcL sequences, the two subgenera diverged 18-39 million years ago whereas species within each subgenus diverged more recently.\ud These results support the current division of Ceanothus into two monophyletic subgenera\ud and agree with the postulated recent divergence of many species within each subgenus.\ud Specificity between Ceanothus species and their Frankia microsymbionts was\ud evaluated by analysis of DNA in nodules collected from three copopulations of\ud Ceanothus species. Sequencing of the intergenic spacer region between 16S and 23S rRNA genes suggested that Ceanothus-microsymbiont Frankia are closely related.\ud Nodules were further analyzed by genomic fingerprinting using repetitive sequences and\ud PCR (rep-PCR). A newly designed, direct repeat sequence and a BOX sequence showed\ud that Ceanothus-microsymbiont Frankia exhibited less diversity within each copopulation\ud than among copopulations. Furthermore, geographic separation was a more important\ud factor for divergence of Ceanothus-microsymbiont Frankia than host plant.\ud The population of Ceanothus-infective Frankia in soils under stands of Ceanothus\ud velutinus and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), a non-host plant, were\ud compared. The population sizes were measured using plant bioassay methods with C.\ud velutinus, C. sanguineus, and C. integerrimus as trap plants. Population size in soil under\ud C. velutinus was about 10 times higher than that under the Douglas-fir. Nodulation\ud capacities of the three trap plants were not significantly different. The diversity of\ud Frankia nodulating trap plants was examined using rep-PCR. Results suggested that\ud infective Frankia is not species-specific with regard to the three Ceanothus species used\ud as trap plants and that although the degree of diversity was similar in both soils, the two\ud populations consisted of different Frankia

Year: 1997
OAI identifier: oai:ir.library.oregonstate.edu:1957/34006
Provided by: ScholarsArchive@OSU

Suggested articles

Preview

Citations

  1. (1986). A 26-base-pair repetitive sequence specific for Neisseria gonorrhoeae and Neisseria meningitidis genomic
  2. (1982). A cumulative listing of isolated frankiae, the symbiotic, nitrogenfixing actinomycetes.
  3. (1992). A highly conserved repeated DNA element located in the chromosome of Streptococcus pneumoniae. Nucleic Acids Res. doi
  4. (1976). A microscopic study of the development of a sporelike stage in the life cycle of the root nodule endophyte of Alnus glutinosa (L.) Vill. doi
  5. (1984). A modified sucrose fractionation procedure for the isolation of frankiae from actinorhizal root nodules and soil samples. doi
  6. (1969). A treatise on Dinitrogen Fixation Section 3, Biology. doi
  7. (1986). Amplification of 16S rRNA genes from Frankia strains in root nodules of Ceanothus griseus, Coriaria arborea, Coriaria plumosa, Discaria toumatou, and Purshia tridentata.
  8. (1996). An integrated map of the genome of the tubercle bacillus, Myrobacterium tuberculosis H37Rv , and comparison with Mycobacterium leprae. doi
  9. (1992). Analysis of a ribosomal RNA operon in the actinomycete Frankia. Gene 111:119-124 doi
  10. (1993). Biology of Frankia strains, actinomycete symbionts of actinorhizal plants. doi
  11. (1994). Calcium and pH interaction on root nodulation of nursery grown red alder (Alnus rubra Bong.) seedlings by Frankia. doi
  12. (1995). Chloroplast gene sequence data suggest a single origin of the predisposition for symbiotic nitrogen fixation in angiosperms. doi
  13. (1983). Dinitrogen fixation in forest ecosystems. doi
  14. (1994). Disparate rates of molecular evolution in cospeciating hosts and parasites. doi
  15. (1986). Distribution of spore-positive and spore-negative nodules in stands of Alnus glutinosa and Alnus incana in Finland. Plant Soil 96:205-213 doi
  16. (1982). Evaluation of Frankia strains isolated from provenances of two Alnus species. doi
  17. (1994). Functional constraints and rbcL evidence for land plant phylogeny. doi
  18. (1996). Genetic diversity among Frankia strains nodulating members of the family Casuarinaceae in Australia revealed by PCR and restriction fragment length polymorphism analysis with crushed root nodules.
  19. Genomic fingerprinting of bacteria using repetitive sequence-based polymerase chain reaction.
  20. (1992). Grouping of Frankia strains on the basis of DNA relatedness. doi
  21. (1988). Host range differentiation of sporepositive and spore-negative strain types of Frankia in stands of Alnus glutinosa and Alnus incana in Finland. doi
  22. (1990). Identification of Frankia strains in nodules by hybridization of polymerase chain reaction products with strainspecific oligonucleotide probes. doi
  23. (1997). Molecular phylogeny of the genus Ceanothus using ndhF and rbcL sequences. doi
  24. (1995). ndhF sequence evolution and the major clades in the sunflower family. doi
  25. (1979). Nitrogen fixation by Ceanothus velutinus in northeastern Oregon.
  26. (1989). Occurrence and activity of hydrogenase in symbiotic Frankia from field-collected Alnus incana. doi
  27. PAUP: phylogenetic analysis using parsimony, version 3.0. Illinois National History Survey,
  28. (1987). Phylogenetics of seed plants: An analysis of nucleotide sequences from the plastid gene
  29. (1973). Some soil factors affecting snowbrush nodulation.
  30. (1994). Specific genomic fingerprinting of phytopathogenic Xanthomonas and Pseudomonas pathovars and strains generated with repetitive sequences
  31. (1987). Stabilization of translationally active mRNA by prokaryotic REP sequences. doi
  32. (1995). Studies oftwo Frankia strains isolated from Trevoa trinervis Miers. doi
  33. (1989). The evolution of specificity in the legumerhizobium symbiosis. Trends Ecol. Evol.
  34. (1992). The nodular endophytes of Coriaria spp. form a distinct lineage within the genus Frankia. doi
  35. (1971). The probabilities of rooted tree-shapes generated by random bifurcation. doi
  36. (1980). Ubiquitous, interspersed repeated sequences in mammalian genomes. doi

To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.