Greedy scale (Homoptera: Diaspididae) phenology on taraire based on Julian day and degree-day accumulations

In northern New Zealand, greedy scale, Hemiberlesia rapax (Comstock), infests kiwifruit, Actinidia deliciosa (Chevalier) C. F. Liang et A. R. Ferguson variety deliciosa, by aerial invasion from adjacent host plants such as taraire, Beilshmiedia tarairi Bentham and Hooker. Greedy scale was monitored over 3 seasons using leaf samples from taraire trees adjacent to a commercial kiwifruit orchard. The seasonality of stage-specific population peaks and troughs was estimated using a Bayesian smoothing technique for both degree-day (DD) accumulations and Julian days. Two generations were observed with peaks for the 1st, 2nd, 3rd instars, and mature stages occurring on 30 December, 4 February, 17 March, and 18 April, respectively, for the summer generation, and 12 March, 13 April, 3 June, and 2 July, respectively, for the winter generation. Field populations of greedy scale were well described by physiological time; therefore, opportunities exist for predicting stage-specific events. Total developmental time using a base temperature of 9.3 degrees C was estimated at 1,056 DD with a standard error of 34 DD