Seasonal temperatures and the phenology of greedy scale populations (Homoptera: Diaspididae) on kiwifruit vines in New Zealand

Abstract

The development rate response to temperature of greedy scale, Hemiberlesia rapax, instars was determined from development times over a range of constant temperatures. A diurnal temperature simulation technique employing sine and exponential functions was coupled with these relationships and used to drive a distributed development period model of greedy scale phenology. The model was assessed against field data for its ability to predict first instar presence at one site in the Waikato, New Zealand. The model was then used to examine possible seasonal variation in the timing of first instar greedy scale production over the range of kiwifruit growing climates in New Zealand. The model duplicated field data for first instar presence well. The results obtained from simulations for a range of seasons and districts are discussed. © 1994 The Royal Society of New Zealand.