Thermal requirements and age-specific life tables of Myzus persicae (Sulzer) (Hemiptera: Aphididae) in laboratory

This study aimed to determine the thermal requirements of the green peach aphid, Myzus persicae (Sulzer), to calculate age-specific life tables, and to predict the occurrence of adults in the field by a degree-day model. The aphids were reared, individualized, in leaf cages set on kale, Brassica oleracea L. var. acephala DC., kept at 15, 20, 23, 25 and 30°C, in laboratory. The lowest developmental thermal threshold (Tb) was 2.2°C and the thermal constant (K) was 165.6 day-degree. The degree-day model predicted the occurrence of adults 0-1 day before the time they were first observed in the field. The age-specific life table parameters, on a degree-day time scale, indicated that the temperatures 23°C and 25°C provided the best thermal conditions for the population growth of M. persicae. At these temperatures the highest intrinsic rate of natural increase (r m = 0.012) was observed as well as the lowest mean generation time (T = 303.8 degree-day and T = 272 degree-day, respectively) and population doubling time (TD = 57.8 degree-day).

Green peach aphid; temperature; degree-day; population dynamics; Brassica oleracea