Dickeya fangzhongdai, a bacterial pathogen of taro (Colocasia esculenta), onion (Allium sp.), and several species in the orchid family (Orchidaceae) causes soft rot and bleeding canker diseases. No field-deployable diagnostic tool is available for specific detection of this pathogen in different plant tissues.
View Article and Find Full Text PDFPectobacterium parmentieri (formerly Pectobacterium wasabiae), which causes soft rot disease in potatoes, is a newly established species of pectinolytic bacteria within the family Pectobacteriaceae. Despite serious damage caused to the potato industry worldwide, no field-deployable diagnostic tests are available to detect the pathogen in plant samples. In this study, we aimed to develop a reliable, rapid, field-deployable loop-mediated isothermal amplification (LAMP) assay for the specific detection of P.
View Article and Find Full Text PDFis a toxigenic bacterial pathogen of several grass species and is responsible for massive livestock deaths in Australia and South Africa. Due to concern for animal health and livestock industries, it was designated a U.S.
View Article and Find Full Text PDFClavibacter is an agriculturally important bacterial genus comprising nine host-specific species/subspecies including C. nebraskensis (Cn), which causes Goss's wilt and blight of maize. A robust, simple, and field-deployable method is required to specifically detect Cn in infected plants and distinguish it from other Clavibacter species for quarantine purposes and timely disease management.
View Article and Find Full Text PDFRathayibacter toxicus is a toxigenic bacterial plant pathogen indigenous to Australia and South Africa. A threat to livestock industries globally, the bacterium was designated a U.S.
View Article and Find Full Text PDFis a Gram-positive, nematode-vectored bacterium that infects several grass species in the family Poaceae. Unique in its genus, has the smallest genome, possesses a complete CRISPR-Cas system, a vancomycin-resistance cassette, produces tunicamycin, a corynetoxin responsible for livestock deaths in Australia, and is designated a Select Agent in the United States. In-depth, genome-wide analyses performed in this study support the previously designated five genetic populations, with a core genome comprising approximately 80% of the genome for all populations.
View Article and Find Full Text PDFClavibacter is an agriculturally important genus comprising a single species, Clavibacter michiganensis, and multiple subspecies, including, C. michiganensis subsp. nebraskensis which causes Goss's wilt/blight of corn, accounts for high yield losses and is listed among the five most significant diseases of corn in the United States of America.
View Article and Find Full Text PDFThis is a response to a recent Letter to the Editor of Phytopathology, in which Gupta et al. (2019) caution against the indiscriminate use of the MoT3 diagnostic assay that distinguishes isolates of Magnaporthe oryzae in the Triticum lineage from those that do not cause aggressive wheat blast. We confirm that the assay does reliably distinguish between wheat and rice isolates from Bangladesh and worldwide, as described in the original paper by Pieck et al.
View Article and Find Full Text PDFWheat blast, caused by the Magnaporthe oryzae Triticum pathotype, is an economically important fungal disease of wheat. Wheat blast symptoms are similar to Fusarium head scab and can cause confusion in the field. Currently, no in-field diagnostic exists for M.
View Article and Find Full Text PDFWheat blast has emerged as a major threat to wheat production in South America. Although originally restricted to Brazil, the disease has since been observed in the neighboring countries of Argentina, Bolivia, and Paraguay and recently the pathogen, Magnaporthe oryzae Triticum pathotype, was isolated from infected wheat in Bangladesh. There is growing concern that the pathogen may continue to spread to other parts of the world, including the United States, where several M.
View Article and Find Full Text PDFWheat blast, caused by the Triticum pathotype of Magnaporthe oryzae, is an emerging disease considered to be a limiting factor to wheat production in various countries. Given the importance of wheat blast as a high-consequence plant disease, weather-based infection models were used to estimate the probabilities of M. oryzae Triticum establishment and wheat blast outbreaks in the United States.
View Article and Find Full Text PDFRathayibacter toxicus is a gram-positive bacterium that infects the floral parts of several Poaceae species in Australia. Bacterial ooze is often produced on the surface of infected plants and bacterial galls are produced in place of seed. R.
View Article and Find Full Text PDFThe National Plant Diagnostic Network (NPDN) has developed into a critical component of the plant biosecurity infrastructure of the United States. The vision set forth in 2002 for a distributed but coordinated system of plant diagnostic laboratories at land grant universities and state departments of agriculture has been realized. NPDN, in concept and in practice, has become a model for cooperation among the public and private entities necessary to protect our natural and agricultural plant resources.
View Article and Find Full Text PDFMagnaporthe oryzae is the causal agent of blast disease on several graminaceous plants. The M. oryzae population causing wheat blast has not been officially reported outside South America.
View Article and Find Full Text PDFABSTRACT Pseudomonas spp. have been studied for decades as model organisms for biological control of plant disease. Currently, there are three commercial formulations of pseudomonads registered with the U.
View Article and Find Full Text PDFIn 2006, a mechanically-transmissible and previously uncharacterized virus was isolated in Kansas from wheat plants with mosaic symptoms. The physiochemical properties of the virus were examined by purification on cesium chloride density gradients, electron microscopy, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), sequencing of the nucleotides and amino acids of the coat protein, and immunological reactivity. Purified preparations contained flexuous, rod-shaped particles that resembled potyviruses.
View Article and Find Full Text PDFDisease phenotypes for winter wheat cultivars were determined in numerous inoculated greenhouse and field experiments over many years. For four diseases, Fusarium head blight, tan spot, Septoria leaf blotch, and Stagonospora leaf blotch, at least 20 cultivars each had been evaluated in a minimum of five experiments. Reference cultivars of known disease reaction were included in each experiment, which allowed transformation of the percent disease severity data to a 1-to-9 scale for comparisons between experiments.
View Article and Find Full Text PDFPanicle diseases are among the major constraints to sorghum (Sorghum bicolor) production in the northern Great Plains; host plant resistance is the primary management option. However, essentially all commercial sorghum hybrids contain A cytoplasm, which raises the concern about increased disease risk as a result of cytoplasmic genetic uniformity. To determine the influence of cytoplasmic background on the expression of susceptibility to panicle diseases, F hybrids with four nuclear genotypes in each of two cytoplasms (A and A) were planted in three environmentally diverse geographic locations in Nebraska.
View Article and Find Full Text PDF