Environmental Entomology (2007) 36, 1154-1158

W.H. Day (2007)
Effect of host instar on measuring parasitism of Lygus spp. (Hemiptera: Miridae) nymphs by Peristenus spp. (Hymenoptera: Braconidae)
Environmental Entomology 36 (5), 1154-1158
Abstract: The accurate measurement of insect mortality by parasites is critical in biological control research, both in baseline studies to determine the absence or inadequacy of native parasites and in subsequent efforts to measure the effectiveness of introduced endoparasitic species. Although rearing has been most frequently used to measure parasitism, dissection has been shown to be more accurate in several cases. Selection of the host instar, whether for rearing or dissection, was also found to be important in this study. In two species [Lygus lineolaris (Palisot) and L. hesperus Knight], parasitism by Peristenus digoneutis Loan and P. howardi Shaw, respectively, was highest in instars 3 and 4. Parasitism was underestimated in instars 1 and 2 (because of reduced exposure time) and in instar 5 (because of parasites killing the hosts in instar 4).
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Link to article at publishers website

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
surveys/distribution/isolation

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Lygus lineolaris
	Lygus hesperus
Peristenus digoneutis (parasitoid)	Lygus lineolaris
Peristenus howardi (parasitoid)	Lygus hesperus