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Managing Quarantine-Significant Post Harvest Diseases in Pacific Northwest Apple and Pear Orchards

Video Summary

In this video Drs. Parama Sikdar, Mike Willett, Richard Kim and Mr. Tom Auvil provide a tutorial about the management of two quarantine significant postharvest diseases in apple orchards of Washington State. These include speck rot caused by Phacidiopycnis washingtonensis and Sphaeropsis rot caused by Sphaeropsis pyriputrescens.


Dr. Parama Sikdar introduces the two diseases, their first report and disease cycle. Dr. Mike Willett, then provides information about the ban on export of apples to Chinese markets from 2012-2014 due to the occurrence of these two quarantine specific diseases in shipped fruit. He further elaborates on the management practices required by the Chinese government for the market to remain open for the export of Red Delicious and other varieties of apple. Dr. Richard Kim provides important advice on how to control infection in the orchard to control the postharvest incidence of the disease at harvest and before storage in packing houses. In the orchard, Mr. Tom Auvil demonstrates how to prune the Manchurian crabapple pollenizer that is a source of inoculum for apple fruit infection in the orchard. He provides information on the right technique to remove the pendant limbs, and how soon or often the crabapple trees should be pruned in order to avoid the incidence of latent fruit infection in orchard. The video also provides insights on future project research to replace the Manchurian crabapple with other suitable crabapple genotypes under the direction of Dr. Stefano Musacchi. Finally, Dr. Sikdar provides information on the other hosts and geographic spread of Phacidiopycnis washingtonensis.

Speakers: Dr. Parama Sikdar, Washington State University; Dr. Mike Willett, Northwest Horticultural Council; Dr. Richard Kim, Pace International; and Mr. Tom Auvil, Washington Tree Fruit Research Commission

Washington State University