FLIGHT ACTIVITY OF 2 SPECIES OF THE DELIA GENUS (DIPTERA, ANTHOMYIIDAE) IN SOUTHWESTERN SLOVAKIA

Flight activity of local populations of the cabbage root fly (Delia ra dicum) and the seedcorn maggot D. platura has been monitored at Borska nizina lowland in the course of 1990 and 1998. Investigated species o f root maggots have been completing two generations per year and the o nset of a third one seemed to be in preparation. Activity peaks of fir st generation adults have been divided into early- and late-emerging f lies. One part of the second-generation flies has emerged without aest ivation the other ones' development continued after aestivation. Therm al requirements for the development of individual generations have bee n established.