Electrophoretic karyotypes were obtained from intact cells of four wild
type strains of Tilletia caries and T. controversa, and 5 inter specific hybrid
progeny using clamped homogeneous electric field, pulsed field gel
electrophoresis (CHEF PFGE). Each karyotype was polymorphic and unique
relative to the other strains. However, the relative size...
A strain of the phytopathogenic bacterium Pseudomonas syringae
pv. phaseolicola, a pathogen of common bean Phaseolus vulgaris,
harbors a 150 kilobase pair (kb) plasmid pMC7105. In one strain,
LR719, pMC7105 is stably integrated in the bacterial chromosome.
Imprecise excision of the pMC7105 replicon has been shown to result
in the...
Genetic studies of Tilletia spp. have been hampered by the lack
of genetic markers. The work discussed here is a first report of the
isolation of genetically marked strains of J. caries and their use in
wheat plant infection studies. Procedures for the isolation of auxotrophic and drug-resistant mutants in...
Pulsed-field gel electrophoresis (PFGE) of the strains representing the 14 races of
U. hordei, the causal agent of covered smut on barley, revealed extensive polymorphism
in chromosome length and number. The purpose of this study was to determine by two
approaches the exact chromosome number for each U. hordei race,...
1S801 is a transposable element isolated from Pseudomonas syringae pathovar
(pv.) phaseolicola, the causal agent of halo blight of bean. Fragments of the element are
present in multiple copies on an indigenous plasmid, pMMC7105, of strain LR781, and
have been implicated as sites of homologous recombination leading to imprecise
excision...
Inbreeding of the avirulent physiologic race 8 strains of Ustilago hordei was
purported to have increased its pathogenicity in a stepwise manner that led to a highly
pathogenic race, designated race 14. The analysis of electrophoretic karyotypes and
restriction fragment length polymorphism profiles detected with a telomere-specific probe
(TelomereRFLP) in...
A pathogenicity locus of Pseudomonas syringae pv.
syringae identified by Tn5 mutagenesis was investigated.
The mutant strain PS9024 is attenuated for disease
expression in its host, Phaseolus vulgaris, but produces
the hypersensitive reaction (HR) in the nonhost, tobacco
(Nicotina tabacum). A cosmid clone carrying 16 kilobases
(kb) of contiguous genomic...