Biocontrol Science and Technology (2005) 15, 571-583

D.R. Gillespie and D.M.J. Quiring (2005)
Diapause induction under greenhouse conditions in two populations of Dicyphus hesperus (Hemiptera: Miridae)
Biocontrol Science and Technology 15 (6), 571-583
Abstract: The effects of daylength on induction of reproductive diapause were investigated in two populations of Dicyphus hesperus to determine which was more suitable as a biological control in greenhouses without supplemental light. A population from British Columbia Canada (49°36' N Lat.) had a critical daylength of about 15.5 h, whereas that of a population from California, USA (35°43' N Lat.) was between 14.0 and 13.5 h. Under natural daylengths in greenhouses at 49°N Lat., females of both populations exhibited reproductive diapause at a daylength that was consistent with their respective critical daylengths. In spring, a lower proportion of both populations diapaused when exposed to diapause-inducing conditions than in autumn. Reproductive diapause of the females of the BC population was 100% in autumn, but half of those females laid eggs when held in the greenhouse for 6 weeks. A maximum of 63% of females of the California population diapaused in autumn, and most began to lay eggs after 2 weeks. The differences in response to daylength presumably reflect differences between the two localities in the reliability of the critical daylength as a predictor of conditions unsuitable for growth and reproduction. Under greenhouse conditions the California population is essentially non-diapausing, and would be the more suitable of the two populations for use as a biological control agent.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): David R. Gillespie

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
environment/habitat manipulation
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
Dicyphus hesperus (predator)			U.S.A. (SW)
Dicyphus hesperus (predator)			Canada (west)