Publications by authors named "Rebecca E Spanner"

Sugar beet () is grown in temperate regions around the world as a source of sucrose used for natural sweetening. Sugar beet is susceptible to a number of viral diseases, but identification of the causal agent(s) under field conditions is often difficult due to mixtures of viruses that may be responsible for disease symptoms. In this study, the application of RNAseq to RNA extracted from diseased sugar beet roots obtained from the field and from greenhouse-reared plants grown in soil infested with the virus disease rhizomania (causal agent beet necrotic yellow vein virus; BNYVV) yielded genome-length sequences from BNYVV, as well as beet soil-borne virus (BSBV).

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Cercospora beticola is a hemibiotrophic fungus that causes cercospora leaf spot disease of sugar beet (Beta vulgaris). After an initial symptomless biotrophic phase of colonization, necrotic lesions appear on host leaves as the fungus switches to a necrotrophic lifestyle. The phytotoxic secondary metabolite cercosporin has been shown to facilitate fungal virulence for several Cercospora spp.

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Unlabelled: Cercospora leaf spot, caused by the fungal pathogen Cercospora beticola, is the most destructive foliar disease of sugar beet worldwide. This review discusses C. beticola genetics, genomics, and biology and summarizes our current understanding of the molecular interactions that occur between C.

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Perylenequinones are a family of structurally related polyketide fungal toxins with nearly universal toxicity. These photosensitizing compounds absorb light energy which enables them to generate reactive oxygen species that damage host cells. This potent mechanism serves as an effective weapon for plant pathogens in disease or niche establishment.

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Species in the genus cause economically devastating diseases in sugar beet, maize, rice, soy bean, and other major food crops. Here, we sequenced the genome of the sugar beet pathogen and found it encodes 63 putative secondary metabolite gene clusters, including the cercosporin toxin biosynthesis () cluster. We show that the gene cluster has experienced multiple duplications and horizontal transfers across a spectrum of plant pathogenic fungi, including the wide-host range genus as well as the rice pathogen Although cercosporin biosynthesis has been thought to rely on an eight-gene cluster, our phylogenomic analysis revealed gene collinearity adjacent to the established cluster in all cluster-harboring species.

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