Pear stony pit
Unknown, virus suspected
Dark-green spots appear on developing fruit about two to three weeks after petal fall. The tissue around the affected areas continues to grow, forming deep pits. Older pits develop necrotic centers. Heavily infected fruit are often severely deformed, gritty, and difficult to slice through (A). Doing so, however, reveals pitting throughout.
Widespread; it is the most important viral disease of pear.
Similar symptoms can be caused by the pear plant bug.
Pear stony pit is almost exclusively managed in the nursery through the use of disease-free propagated material. In the orchard, trees affected one year may not be affected in subsequent years.
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