Environmental Entomology (1989) 18, 223-227

Daniel J. Burden and Elwood R. Hart (1989)
Degree-day model for egg eclosion of the pine needle scale (Hemiptera: Diaspididae)
Environmental Entomology 18 (2), 223-227
Abstract: Eclosion of overwintering eggs of pine needle scale, Chionaspis pinifoliae (Fitch), was modeled from growth chamber fluctuating temperature rearings. A computer model, DEGDAY, was used to determine daily and accumulated degree-day accumulations to hatch. This model and simple regression techniques were used to identify the developmental threshold. Percentage of survivorship ranged from 0 at 9°C to 98 at 18.5°C. At 18.5°C, 136 degree-days accumulated to hatch, and time to 50% hatch was 17.25 d. The developmental threshold lies between 10.8 and 11.8°C.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Database assignments for author(s): Elwood R. Hart

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

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Chionaspis pinifoliae		U.S.A. (mid N)