Environmental Entomology (1981) 10, 279-284

Jose Morales and Arthur A. Hower (1981)
Thermal requirements for development of the parasite Microctonus aethiopoides
Environmental Entomology 10 (3), 279-284
Abstract: The thermal requirements for development of Microctonus aethiopoides Loan were studied under laboratory and field conditions. Laboratory studies indicated that the threshold temperature for development of M. aethiopoides larval and pupal stages was 8.4°C (47.2°F). The relationship between temperature and duration in days for development was linear within the range of temperatures supporting complete development (r² = 0.97). Averages of 222 and 240 Fahrenheit degree days (F°D) were required for development of the larval and pupal stages, respectively. Larval plus pupal development required an average of 469 PD.
Degree days in the field were accumulated beginning 1 January, and based on a threshold for development of 47.2°F. During 2 years of study, 50% of the first and second generations emerged when means of 463 and 484 F°D, respectively, had accumulated. These data validated the use of °D, as computed in the laboratory, to forecast periodicity of M. aethiopoides adults in the field.
The ability to predict parasite development would be helpful for collecting, rearing, and further releases of this insect in the field. This information would also be useful in timing of insecticide sprays to avoid the demise of the parasites.
(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:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution
environment/habitat manipulation

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Hypera postica	Alfalfa/lucerne (Medicago sativa)	U.S.A. (NE)
Microctonus aethiopoides (parasitoid)	Hypera postica		U.S.A. (NE)