Report on Tyrophagus neiswanderi (Acari: Acaridae) as a Pest of Greenhouse Cucumber in Korea

Mites were collected from organic cultivations of greenhouse cucumbers and identified as Tyrophagus neiswanderi (Acari: caridae). T. neiswanderi (length, width, ) is a very small, milky-white, and egg-shaped mite, and it mainly causes damage to the leaves, flowers, and fruits of cucumber plants. In the early growing season of cucumbers, the shoots of seedlings became pale and yellow because of T. neiswanderi, and eventually shrinkage or bud-failing was observed in the plants. In the middle of the growing season, T. neiswanderi caused white spots on the leaves and flowers of the plants, and the spots gradually became holes. T. neiswanderi also caused severe damage to young fruits by feeding on the rinds of the fruits, inducing malformations and lowering the economic value.