jamesonii. They shared RAPD markers with the tested representatives of the forma specialis chrysanthemi. Some isolates

of those tested from diseased G. jamesonii were placed in a different cluster, which included representative isolates of forma specialis tracheiphilum. This is the first report of F. oxysporum f.sp. tracheiphilum on G. jamesonii. A rapid protocol for DNA extraction directly from fungal colonies grown on potato dextrose agar allowed complete analysis in less than 4 h. “
“Mango malformation has become the most important global disease on mango. Fusarium species previously associated with this disease include F. mangiferae, F. mexicanum, F. sterilihyphosum, F. proliferatum, F. subglutinans and F. tupiense. A few strains of F. proliferatum have been reported from MI-503 Malaysia, but in this study, we report the results

of more extensive sampling. The recovered strains selleck chemicals llc were evaluated with morphology, mating tester strain cross-fertility, amplified fragment length polymorphisms (AFLPs), and partial DNA sequences of the genes encoding translation elongation factor 1-α (tef-1α) and β-tubulin (tub-2). Amongst the 43 strains evaluated, three species were identified – F. proliferatum, F. mangiferae and F. subglutinans – with F. proliferatum being the most frequent (69%). None of the Fusarium species that appear to originate in the Americas were recovered in Malaysia, which suggests special measures may be warranted to keep these species from entering the country. “
“This paper describes the development of a polymerase chain reaction (PCR) assay for the detection of Phytophthora nicotianae, the causal agent of Phytophthora blight of tobacco and other plants. The PCR primers were designed based on a Ras-related protein (Ypt1) gene, and 115 isolates representing 26 species of Phytophthora and 29 fungal species of plant pathogens were used to test the specificity of the primers. PCR amplification with species-specific (Pn) primers resulted in a product of 389 bp only from isolates of P. nicotianae. The detection sensitivity with Pn medchemexpress primers was 1 ng of genomic DNA. Using Ypt1F/Ypt1R as first-round amplification primers, followed by a second round using the primer

pair Pn1/Pn2, a nested PCR procedure was developed, which increased the detection sensitivity 100-fold to 10 pg. PCR with the Pn primers could also be used to detect P. nicotianae from naturally infected tobacco tissues and soil. The PCR-based methods developed here could simplify both plant disease diagnosis and pathogen monitoring as well as guide plant disease management. “
“The epiphyte Pseudomonas syringae pv. syringae 22d / 93 (Pss22d), isolated from soybean leaves, had been characterized as a promising and species-specific biocontrol strain in vitro and in planta against the plant pathogen P. syringae pv. glycinea (Psg), which causes bacterial blight of soybean. Three toxins are known to be produced by Pss22d: syringomycin, syringopeptin and 3-methylarginine (MeArg).