Environmental Entomology (2016) 45, 1515-1520

Jessica A. Hartshorn, Kevin D. Chase, Larry D. Galligan, John J. Riggins and Fred M. Stephen (2016)
Interactions among latitude, nematode parasitization, and female Sirex nigricornis (Hymenoptera: Siricidae) fitness
Environmental Entomology 45 (6), 1515-1520
Abstract: Sirex nigricornis F. (Hymenoptera: Siricidae) is an innocuous pine-inhabiting woodwasp native to eastern North America, utilizing dead or dying pine trees as hosts. Although S. nigricornis F. does not cause economic damage, a closely related species, Sirex noctilio, was discovered in New York in 2004 and has continually spread throughout the northeastern United States and southern Canada, threatening the multi-billion-dollar pine timber industry of the southeastern United States and raising interest about potential interactions with native woodwasps and associated mortality agents. A non-sterilizing strain of the biological control agent, Deladenus siricidicola Bedding (Tylenchida: Neotylenchidae), was introduced along with S. noctilio but is not inhibiting the spread or establishment of S. noctilio. A North American congener, Deladenus proximus Bedding, has been recently isolated from S. noctilio and shows promise as a biological control agent. To better understand the potential of D. proximus as a control agent for S. noctilio, we measured and dissected nearly 1,200 S. nigricornis females from Arkansas and Mississippi and evaluated differences among collection location with regard to nematode virulence, woodwasp body size, and egg load. Body size and egg load were related to collection location, and nematode infestation resulted in significantly smaller females who produced significantly fewer eggs. Female woodwasps, especially those collected in Arkansas, were often fully sterilized by nematodes, and a higher percent sterilization was inversely related to body size and fewer eggs. We propose field studies to test the nematode's ability to sterilize S. noctilio in the northeastern United States.
(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): Jessica A. Hartshorn, Fred M. Stephen

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

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Sirex noctilio
Deladenus proximus (entomopathogen)	Sirex noctilio		U.S.A. (mid S)