Crop protection in European greenhouses became strongly chemically oriented shortly after
the Second World War in the 1950s. But an excellent climate for fast reproduction of pests
and diseases demanded high spray frequencies and, thus, resulted in quick development of
resistance against pesticides. This initiated a search for alternatives of chemical pesticides.
The first natural enemies for control of pests in European greenhouse vegetables became
available in the 1960s. A change from chemical control to very advanced integrated pest …