Developmental parameters and voltinism of the painted apple moth, Teia anartoides Walker (Lepidoptera: Lymantriidae) in New Zealand

Abstract

Key developmental parameters, including the lower threshold temperature for development and thermal accumulation requirements, of T. anartoides reared on an artificial diet were determined. The median number of days required to complete development was measured for each life stage at constant mean temperatures of 6.7, 10.2, 12.6, 17.7, 21.9, 22.5 and 30°C. Rate of development was a linear function of temperature over a range that can be realistically expected in New Zealand, and minimum rates of development were estimated by extrapolation. Eggs failed to emerge at temperatures below 10.2°C. Some neonate larvae survived for 60 days at 6.7°C, but failed to develop. At higher temperatures, larvae usually developed through 4 and 5 instars to males and females respectively, with generation developmental times of 71 and 76 days at 17.7°C, and 33 and 34 days at 30°C (for males and females respectively). Optimum temperatures for development lay between 17.7 and 22.5°C. Female developmental requirements above a base temperature of 9.6°C were 616 day-degrees per generation, consisting of 119 day-degrees for egg hatch plus 497 day-degrees for larval and pupal development. Historical weather data from sites around New Zealand suggest that T. anartoides might develop through 1.4 generations/year in the south of the South Island and 4 generations/year in the north of the North Island. The data indicate that the moth might realistically establish at any coastal site around New Zealand, and vary from uni-voltine in the south to tri-voltine in the north, depending on a number of factors including host plant.