How to Manage Pests

Pests in Gardens and Landscapes

Pear decline

Pear decline is caused by a microorganism called a mycoplasma, which is spread by pear psylla. Trees with pear decline have poor shoot and spur growth, dieback of shoots, upper rolling of leaves, reduced leaf and fruit size, and premature leaf drop. Sudden tree collapse can result from tissue damage at the graft union on highly susceptible rootstocks, but slow decline is more common.

Life cycle

Solutions

Some tolerant rootstocks may be available. To keep the disease in remission on susceptible rootstocks, control pear psylla and maintain trees in good vigor; reduce stress caused by inadequate irrigation, nutrient deficiency, weed competition, and lack of pruning. Consider replacing trees on susceptible rootstocks with resistant ones.

Rolling and discoloration of leaves
Rolling and discoloration of leaves


Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2014 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance.

Agriculture and Natural Resources, University of California

Accessibility   /PMG/GARDEN/FRUIT/DISEASE/peardecline.html revised: April 25, 2014. Contact webmaster.