EFFECTS OF PESTICIDES
In the last 30 years investigations into side-effects of pesticides on beneficial organisms have gained more and more importance. The increase in knowledge is the basis for reducing the undesirable effects of pesticide applications, which among others, is an important principle of integrated production (Cross & Dickler, 1994). Whereas in former years companies presented data on side-effects of a pesticide on a voluntary basis to the authorities for the registration procedure, in 1986 this became obligatory in Germany (Anon., 1986; Brasse, 1990) and recently in all European countries, as regulated by the Council Directive 91/414/EEC. Factors to be considered when studying side-effects were published by Franz (1974). The IOBC/WPRS working group ‘Pesticides and Beneficial Organisms’, founded in 1974, has contributed considerably to research of side-effects caused by pesticides. The group is working (in close co-operation with registration authorities, EPPO) on the development, improvement, and validation of test methods (laboratory, semi-field, and field) and on rearing methods, and it carries out joint testing programmes to investigate the impact of pesticides on about 30 beneficial organisms (Hassan et al., 1983, 1985, 1987, 1988, 1991, 1994; Hassan, 1988, 1989, 1992, 1994; Samsøe-Petersen, 1989; Vogt, 1994; Sterk et al., 1999). Comprehensive data on research findings focusing on the interaction of pesticides with entomophagous arthropods have been published by Croft (1990).