title: In situ hybridization for the detection of rust fungi in paraffin embedded plant tissue sections.
abstract: BACKGROUND
  Rust fungi are obligate pathogens with multiple life stages often including different spore types and multiple plant hosts. While individual rust pathogens are often associated with specific plants, a wide range of plant species are infected with rust fungi. To study the interactions between these important pathogenic fungi and their host plants, one must be able to differentiate fungal tissue from plant tissue. This can be accomplished using the In situ hybridization (ISH) protocol described here.
  
  
  RESULTS
  To validate reproducibility using the ISH protocol, samples of Chrysanthemum × morifolium infected with Puccinia horiana, Gladiolus × hortulanus infected with Uromyces transversalis and Glycine max infected with Phakopsora pachyrhizi were tested alongside uninfected leaf tissue samples. The results of these tests show that this technique clearly distinguishes between rust pathogens and their respective host plant tissues.
  
  
  CONCLUSIONS
  This ISH protocol is applicable to rust fungi and potentially other plant pathogenic fungi as well. It has been shown here that this protocol can be applied to pathogens from different genera of rust fungi with no background staining of plant tissue. We encourage the use of this protocol for the study of plant pathogenic fungi in paraffin embedded sections of host plant tissue.
authors.affiliation: Department of Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA USA.
authors.forename: Mitchell A
authors.initials: MA
authors.lastname: Ellison
authors.affiliation: USDA-ARS Foreign Disease-Weed Science Research Unit, Ft. Detrick, MD USA.
authors.forename: Michael B
authors.initials: MB
authors.lastname: McMahon
authors.affiliation: USDA-ARS Foreign Disease-Weed Science Research Unit, Ft. Detrick, MD USA.
authors.forename: Morris R
authors.initials: MR
authors.lastname: Bonde
authors.affiliation: IR-4 Project, Rutgers University, Princeton, NJ USA.
authors.forename: Cristi L
authors.initials: CL
authors.lastname: Palmer
authors.affiliation: USDA-ARS Foreign Disease-Weed Science Research Unit, Ft. Detrick, MD USA.
authors.forename: Douglas G
authors.identifier: 0000-0002-5789-408X
authors.initials: DG
authors.lastname: Luster
keywords: Basidiomycota; Chrysanthemum × morifolium; Gladiolus × hortulanus; Glycine max; In situ hybridization; Phakopsora pachyrhizi; Puccinia horiana; Pucciniomycotina; Rust fungus; Uromyces transversalis