Knowledge of the viruses which are mechanically transmitted
from pear to herbaceous plants and the diseases they cause in pear
is not complete. This thesis discusses the means used to mechanically
transmit pear viruses, the properties of those viruses and their
relationships with latent viruses of apple.
Herbaceous plant virus...
Published August 1962. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Published June 1925. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Since 1948, pear decline has been responsible for the devitalization
and death of many pear trees in the Pacific Coast states and
British Columbia.
Use of anatomical abnormalities of the graft union as a diagnostic
technique to separate pear decline from other disorders exhibiting
similar symptoms was evaluated. Modifications in...
Published December 1962. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Published June 1925. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Arthropod communities in pear are conceptualized as hierarchically
organized systems in which several levels of organization or subsystems
can be recognized between the species population level and the community
as a whole. An individual tree is taken to be the community habitat with
arthropod subcommunities developing on leaf, fruit and...
Conditions were established for inducing pear blossom blast
caused by Pseudomonas syringae (Ps) on both attached and detached
shoots. The incidence of disease was proportional to the log of Ps
population under optimal temperature, moisture and bloom developmental
stage. Highest incidence of infection followed occurrence of a major
exotherm in...
Published April 1929. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
This publication deals with the development of integrated pest management of insect and mite species that attack pears in southern Oregon. Since about 1900, when the pear industry became firmly established in this area, losses from arthropod pests have been an important and occasionally limiting factor to the continuous production...
Published September 1950. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Since its discovery in Oregon in 1946, the pear psylla, Psylla pyricola Forster, has become the most serious insect pest of pear. Damage to pear trees include the transmission of pear decline disease which has caused losses of trees, injection of a phytotoxic toxin resulting in tree shock and injury,...
Potential sources of inoculum of Phialophora malorum
were investigated. P. malorum was found to be a soil-borne
fungus whose role as a postharvest pathogen of pear is
dependent upon passive dispersal with infested soil. P.
malorum survived in soil under a wide range of conditions,
with greatest survival in cool,...