BASAL THRESHOLD TEMPERATURE AND LIFE CYCLE OF GLOBODERA TABACUM ON EGGPLANT IN RELATION TO ACCUMULATED DAY DEGREES
The basal threshold temperature for development of Globodera tabacum was estimated to be 11 °C. Population dynamics was compared under constant and fluctuating temperatures in growth chambers and in the field experiments respectively, in relation to accumulated degree-days (DD). Completion of the first generation required 70, 34 and 30 days (630, 510 and 570 DD) at 20, 26 and 30 °C respectively; 31 days (476 DD) at field soil temperatures ranging from 23.3 to 29.7. In the field (Campania) four consecutive generations occurred on eggplant requiring 476, 458, 377 and 423 respectively DD. The completion of the fifth generation was arrested by plant removal.