Establishment of the Exotic Mite Orthogalumna terebrantis Wallwork on Water Hyacinth in Bangalore, India

Water hyacinth (Eichhornia crassipes) is the most serious among the 140 species of aquatic weeds recorded in India (Gupta 1979). For biological control trials against this weed, the oribatid mite Orthogalumna terebrantis Wallwork (Acarina : Galumrudae) was introduced from U.S.A. in March 1982 along with two weevils Neochetina eichhorniae Warner and N. bruchi Hustache (Coleoptera : Curculionidae). Releases of N. eichhorniae have already brought about successful control of water hyacinth under field conditions in Bangalore (Jayanth, 1987. 1988) and encouraging results have been obtained with N. bruchi also.