Rodrigues, A.N, Torres, L.M., & Polesny, F. 2001 Phenology of San Jose Scalé, Quadraspidiotus perniciosus (Comstock) on apple in Guarda region (central eastern Portugal).. IOBC/WPRS Bulletin 24(5): 195-199.

Notes: [Proceedings of the IOBC-WPRS Fifth International Conference on Integrated Fruit Protection, Lleida, Spain, 22-26 October, 2000. Avilla, J. & Polesny, F. (Eds.)] San José Scale, Q. perniciosus [Diaspidiotus perniciosus], phenology was studied in an unsprayed apple orchard of the cultivar Golden Delicious, near Guarda (central eastern region of Portugal), during 17 March until 30 November 1997. Three major periods of male flight activity were shown by pheromone traps in this study, for two periods of crawler emergence, which suggest that the insect developed two generations and a partial third one. Spring flight began by the end of March, at 116 degree-days (base 10 °C from 1 March) and occurred until mid-April, during bloom in the apple variety studied. Emergence of first male generation started in the beginning of July at 656 degree-days and continued through mid-September, while that of second generation males, began in mid-September, at 1,535 degree-days and ended by mid-October. First generation crawlers emerged in mid-May, at 326 degree-days and continued to appear through the end of July. Second generation crawlers emerged in mid-August, at 1,161 degree-days and were active throughout November. Approximately 210 degree-days elapsed between first caught of spring males in pheromone traps and the release of first generation crawlers. The use of these data in pest management programmes is discussed.