A number of subgroups of Polymyxa graminis have been separated on the basis of their rDNA sequence. Isolates of P. graminis found on temperate cereals can similarly be divided into two subgroups known as ribotypes I and II. Nothing is known about the biological significance of these ribotypes with regard to host range and virus transmission. Initial studies have been directed towards testing of...

Pseudomonas fluorescens Q8r1-96 produces 2,4-diacetylphloroglucinol (2,4-DAPG), a polyketide antibiotic that suppresses a wide variety of soilborne fungal pathogens, including Gaeumannomyces graminis var. tritici, which causes take-all disease of wheat. Strain Q8r1-96 is representative of the D-genotype of 2,4-DAPG producers, which are exceptional because of their ability to aggressively coloni...

The rhizobacterium Pseudomonas fluorescens CHA0 promotes the growth of various crop plants and protects them against root diseases caused by pathogenic fungi. The main mechanism of disease suppression by this strain is the production of the antifungal compounds 2,4-diacetylphloroglucinol (DAPG) and pyoluteorin (PLT). Direct plant growth promotion can be achieved through solubilization of inorga...

Root diseases have long been prevalent in Australian grain-growing regions, and most management decisions to reduce the risk of yield loss need to be implemented before the crop is sown. The levels of pathogens that cause the major root diseases can be measured using DNA-based services such as PreDicta B. Although these pathogens are often studied individually, in the field they often occur as ...

The main effects of antagonistic rhizobacteria on plant pathogenic fungi are antibiosis, fungistasis or an indirect constraint through the induction of a plant defence response. To explore different biocontrol mechanisms, an in vitro confrontation assay was conducted with the rhizobacterium Pseudomonas fluorescens Pf29Arp as a biocontrol agent of the fungus Gaeumannomyces graminis var. tritici ...

Plants have evolved strategies of stimulating and supporting specific groups of antagonistic microorganisms in the rhizosphere as a defense against diseases caused by soilborne plant pathogens owing to a lack of genetic resistance to some of the most common and widespread soilborne pathogens. Some of the best examples of natural microbial defense of plant roots occur in disease suppressive soil...

Zestaw 478 linii jęczmienia (Hordeum vulgare L.) był badany pod kątem odporności na mączniaka prawdziwego. Badane linie wyprowadzono z odmian miejscowych jarego pochodzących głównie Basenu Morza Śródziemnego. W badaniach wykorzystano trzy izolaty Blumeria graminis o znanym profilu wirulencji. Ocenę wykonano siewkach w warunkach kontrolowanych. Badanie pozwoliło wyselekcjonować 111 odpornych jęc...