ABSTRACT
Genetic diversity within populations of Fusarium pseudograminearum isolated from wheat grains from the Canadian provinces of Alberta and Saskatchewan was investigated. Three restriction enzymes (EcoRI, HaeIII, and PstI) were used to carry out restriction analysis of the nuclear ribosomal DNA (nrDNA) intergenic spacer region (IGS region) and eight primers were used to generate inter-simple sequence-repeat (ISSR) molecular markers. Our study indicated substantially high genetic diversity within these two populations, but low genetic differentiation and frequent gene flow among populations. The IGS data showed no genetic distinction between the two Alberta populations and only minor genetic differentiation between the Saskatchewan and Alberta populations. Analysis of molecular variance indicated that most genetic variability resulted from differences among isolates within populations. Multilocus linkage disequilibrium analysis suggested a panmictic population genetic structure and the occurrence of significant recombination in F. pseudograminearum. Regular gene flow and random mating between isolates from different populations could result in novel genotypes with both improved pathological and biological traits.
Subject(s)
Fusarium/genetics , Plant Diseases/microbiology , Polymorphism, Restriction Fragment Length , Recombination, Genetic , Triticum/microbiology , Canada , DNA, Plant/genetics , DNA, Ribosomal Spacer/genetics , Fusarium/isolation & purification , Genetic Variation , Seeds/microbiologyABSTRACT
Genetic diversity within populations of Fusarium pseudograminearum isolated from wheat grains from the Canadian provinces of Alberta and Saskatchewan was investigated. Three restriction enzymes (EcoRI, HaeIII, and PstI) were used to carry out restriction analysis of the nuclear ribosomal DNA (nrDNA) intergenic spacer region (IGS region) and eight primers were used to generate inter-simple sequence-repeat (ISSR) molecular markers. Our study indicated substantially high genetic diversity within these two populations, but low genetic differentiation and frequent gene flow among populations. The IGS data showed no genetic distinction between the two Alberta populations and only minor genetic differentiation between the Saskatchewan and Alberta populations. Analysis of molecular variance indicated that most genetic variability resulted from differences among isolates within populations. Multilocus linkage disequilibrium analysis suggested a panmictic population genetic structure and the occurrence of significant recombination in F. pseudograminearum. Regular gene flow and random mating between isolates from different populations could result in novel genotypes with both improved pathological and biological traits (AU)
Se investigó la diversidad genética en poblaciones de Fusarium pseudograminearum aisladas de semillas de trigo de las provincias canadienses de Alberta y Saskatchewan. Se usaron tres enzimas de restricción (EcoRI, HaeIII, and PstI) para analizar los marcadores moleculares de las regiones espaciadoras intergénicas (IGS) del DNA ribosómico del núcleo (nrDNA) y de los fragmentos generados entre repeticiones de secuencias sencillas (fragmentos ISSR). Nuestro estudió reveló una gran diversidad genética en ambas poblaciones, pero poca diferenciación genética y un flujo genético frecuente entre las poblaciones. Los datos relativos a las IGS no mostraron diferencias genéticas entre las dos poblaciones de Alberta estudiadas y sólo una ligera diferenciación entre las poblaciones de Alberta y de Saskatchewan. El análisis de la varianza molecular indicó que la variabilidad genética respondía en su mayor parte a diferencias entre aislamientos dentro de las poblaciones. El análisis del desequilibrio en el ligamiento genético sugería una estructura genética de la población de tipo panmíctico y la existencia de una recombinación significativa en F. pseudograminearum. Un flujo genético regular y el apareamiento al azar de aislamientos de poblaciones distintas podría producir nuevos genotipos con características biológicas mejores o patológicas (AU)
