Environmental Entomology (1990) 19, 916-925

D.C. McCain, G.C. Rock and R.E. Stinner (1990)
San Jose scale (Homoptera: Diaspididae): Simulation of seasonal phenology in North Carolina orchards
Environmental Entomology 19 (4), 916-925
Abstract: Orchard temperatures and pheromone trap catch data and crawler hatch data for nine orchard-years were used to validate the accuracy of physiological time models in simulating the time intervals for one generation between male flight peaks, and crawler peaks, as well as the interval between male flight peaks and crawler peaks (embryonic development) of four seasonal generations of the San Jose scale, Quadraspidiotus perniciosus (Comstock) in North Carolina orchards. Linear (degree-days) models simulated within ±1 wk the interval for all male flight peaks between overwintering and F₁ generations, while a nonlinear model simulated within ±1 wk all but one male flight peak between overwintering and F₁ generations. The models were less accurate for simulating intervals of flight peaks between F₁ to F₂ and F₂ to F₃ generations. Likewise, model simulations of the time interval for one generation between crawler hatch peaks, and the time required for embryonic development, were more accurate for F₁ and F₂ than F₃ and F₄ generations. Simulation results of the linear and nonlinear models were similar with 40 of the 49 simulations comparing linear versus nonlinear models not differing by more than 6 d of each other. Validation of the models for San Jose scale was complicated in one apple orchard by the presence of Forbes scale, Quadraspidiotus forbesi (Johnson).
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)

Research topic(s) for pests/diseases/weeds:
population dynamics/ epidemiology
environment - cropping system/rotation

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Diaspidiotus perniciosus	Apple (Malus)	U.S.A. (NW)