Tuesday, December 11, 2007
D0427

Management of rust mites in organically grown pears in Oregon

Silvia Rondon, silvia.rondon@oregonstate.edu and Mahmut Dogramaci, mahmut.dogramaci@oregonstate.edu. Oregon State University, Hermiston Agricultural Research and Extension Center - Crop and Soil Science, 2121 South First Street, Hermiston, OR

The pear rust mite Epitrimerus pyri (Nalepa) (Acari: Eryiophidae) is a serious pest of organic pear production in the northwest. They can reduce the photosynthetic efficiency of leaves and cause russeting on the fruit skin with associated losses in fruit quality, yield and marketability. Due to their size, rust mites are hard to detect and difficult to control especially in organic crops due to the limited availability of organically approved miticides. In this study, we developed a preliminary management strategy that incorporated the temporal and spatial distribution of rust mites with potentially effective chemicals to control the pest. Three organically approved pesticides NeemixR(Azadirachtin), EcotrolR (rosemary and peppermint oils) and EF300R(rosemary oil, sesame oil, thyme, peppermint oil, cinnamon oil) were applied when reached more than 10% rust mite infestation. Results indicated that rust mites prefer to feed on younger leaves with greater numbers of rust mites found in the upper section of the trees compared to the lower section. EF300R significantly reduced rust mite populations compared to control or other treatments. Further studies are needed to develop an IPM strategy for management of rust mites in organic pears.


Species 1: Acari Eriophyidae Epitrimerus pyri (pear rust mite)