Submitted to: Environmental Entomology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 9/22/2009
Publication Date: 4/1/2010
Citation: Brown, M.W., Short, B.D. 2010. Factors affecting appearance of stink bug (Hemiptera: Pentatomidae) injury on apple. Environmental Entomology. 39:134-139. Interpretive Summary: Stink bugs are an increasingly important insect pest of apples in the eastern U.S. damaging fruit before harvest and reducing the price of the fruit due to surface defects. Feeding by stink bugs in late summer is difficult to control due to the harvest re-entry dates of the effective pesticides. This study was done to describe the development of fruit damage from stink bug feeding puncture to the formation of the depressed and discolored surface defect. It was found that not all feeding punctures develop into surface defects and the development of damage is dependent on the fruit cultivar and maturity. It was also found that shading the fruit from sunlight, and especially ultraviolet light, reduced the severity of the fruit surface defect. This indicates that development of the fruit damage is in at least partially due to a light dependent wound response by the fruit. These results will be used by fruit Integrated Pest Management specialists and growers in developing ways to reduce fruit injury from stink bugs by affecting wound response in addition to controlling stink bug populations.
Technical Abstract: Three main types of stink bug injury have been reported on the surface of apple fruit: 1) discolored dots, 2) discolored dots with depressions, and 3) discolored dots with discolored depressions. From 2005 to 2008, studies were performed to determine the factors linked to the variations in the appearance of stink bug injury on apple fruit observed at harvest. The main factors tested were feeding type (i.e. probing vs. sustained feeding), time between injury and evaluation, cultivar, fruit maturity, and relative exposure to sunlight and ultraviolet radiation. No differences were observed due to type of feeding. Studies of the time between injury and evaluation revealed that there is a progression in the development of injury appearance. This progression of injury is influenced by cultivar and relative fruit maturity. Concomitantly, injury sites on fruit exposed to no or limited sunlight and ultraviolet radiation were less likely to develop discolored depressions.