MONITORING OF FLIGHT ACTIVITY IN SOME CRUCIFER-FEEDING PESTS BY MEANS OF YELLOW WATER-TRAPS

Between 1981-1983, yellow water-traps were used to study occurrence of some vegetable pests. Determination was made of temperature thresholds for the flight of Ceutorhynchus quadridens (9.6-degrees-C), C. assimilis (14.6-degrees-C), Meligethes aeneus (10.2-degrees-C), Phyllotreta spp. (10.2-degrees-C), Athalia rosae (17.6-degrees-C), and Delia radicum (8.4-degrees-C). A flight course of overwintering generations of adults of C. quadridens, C. assimilis and M. aeneus was expressed by a derived model based upon the sum of active temperatures for the flight. A day-degree model proved the existence of three generations of A. rosae and D. radicum, the latter being characterised by regular aestivation in part of a population of the first summer generation. Day-degrees are given to assess dates of adult occurrence and period of development of the respective generation. The role of flight activity is discussed for the life cycles of the insect species under study as is the possibility of using yellow water-traps in practical pest control.