Agrobacterium tumefaciens and Agrobacteriwn rhizogenes, the causal agents of crown gall disease and hairy root disease, are known for their ability to transfer part of their
DNA (the T-DNA) from the bacterial tumor-inducing (Ti) plasmid to the genome of the
host plant. Interest has focused on these bacteria because they...
Armillaria (Fr. ex. Fr.) is a parasite whose pathogenicity
and role in forest ecosystems often depends upon the
physiological condition of the tree. Therefore, I tested the
frequency and severity of Armillaria ostoyae (Romagn.) Herink
infection among Abies grandis (Dougl.) Lindl., Larix
occidentalis Nutt., Pinus contorta var. latifolia (Engelm.),
Discusses options for managing major insect pests and diseases of conifers in Oregon forests: bark beetles, wood borers, and ambrosia beetles; defoliators; aphids, adelgids, and scale insects; terminal and branch insects and pitch moths; root diseases; stem decays; foliage diseases; canker diseases and canker-causing rust diseases; and mistletoes. Extensive references...
The root disease fungus Inonotus tomentosus, common in the old
growth boreal forests of British Columbia, poses a threat to the
health of second growth forests established on sites with a previous
history of root disease. Colonized stumps occur in groups of 1 to 6;
the groups are clumped within...