title: Comparative behavior of root pathogens in stems and roots of southeastern Pinus species.
abstract: Root diseases are expected to become a greater threat to trees in the future due to accidental pathogen introductions and predicted climate changes, thus there is a need for accurate and efficient pathogenicity tests. For many root pathogens, these tests have been conducted in stems instead of roots. It, however, remains unclear whether stem and root inoculations are comparable for most fungal species. In this study we compared the growth and damage caused by five root pathogens (Grosmannia huntii, Grosmannia alacris, Leptographium procerum, Leptographium terebrantis, and Heterobasidion irregulare) in root and stem tissue of two Pinus species by inoculating mature trees and tissue amended agar in the laboratory. Most fungal species tested caused greater damage in roots of both pine hosts following inoculation. The relationship between root and stem damage was, however, similar when most combinations of pathogens were compared. These results suggest that although stem inoculations are not suitable for determining the actual damage potential of a given species, they may be viewed as a useful surrogate for root inoculations when comparing the relative pathogenicity of multiple species. When grown on amended agar, fungal species generally had greater growth in stem tissue, contrasting with the findings from tree inoculations.
authors.affiliation: School of Forestry and Wildlife Sciences, Auburn University, 602 Duncan Drive, Auburn, AL 36849-5418, USA. Electronic address: matusge@auburn.edu.
authors.forename: George
authors.initials: G
authors.lastname: Matusick
authors.affiliation: School of Forestry and Wildlife Sciences, Auburn University, 602 Duncan Drive, Auburn, AL 36849-5418, USA.
authors.forename: Ryan L
authors.initials: RL
authors.lastname: Nadel
authors.affiliation: Department of Forest Resources and Environmental Conservation, Virginia Tech University, 4800 Phillips Rd., Hiwassee, VA 24347, USA.
authors.forename: David M
authors.initials: DM
authors.lastname: Walker
authors.affiliation: Department of Biological Sciences, Auburn University, 101 Rouse Life Sciences, Auburn, AL 36849, USA.
authors.forename: Mohammad J
authors.initials: MJ
authors.lastname: Hossain
authors.affiliation: School of Forestry and Wildlife Sciences, Auburn University, 602 Duncan Drive, Auburn, AL 36849-5418, USA.
authors.forename: Lori G
authors.initials: LG
authors.lastname: Eckhardt
mesh_terms: D001487:Basidiomycota / Q000254:growth & development* / Q000472:pathogenicity*; D003470:Culture Media / Q000737:chemistry; D008828:Microbiological Techniques; D055155:Ophiostomatales / Q000254:growth & development / Q000472:pathogenicity*; D028223:Pinus / Q000382:microbiology*; D010935:Plant Diseases / Q000382:microbiology*; D018517:Plant Roots / Q000382:microbiology*; D018547:Plant Stems / Q000382:microbiology*
chemical_list: D003470:Culture Media
keywords: Annosus; Blue-stain; Loblolly; Pathogenicity; Pine; Root disease