Neotropical Entomology (2015) 44, 270-277

C.A. Marchioro, F.S. Krechemer and L.A. Foerster (2015)
Assessing the total mortality caused by two species of Trichogramma on its natural host Plutella xylostella (L.) at different temperatures
Neotropical Entomology 44 (3), 270-277
Abstract: Trichogramma pretiosum Riley and Trichogramma atopovirilia Oatman and Platner are natural enemies of Plutella xylostella (L.) in Southern Brazil. Laboratory studies to evaluate parasitoids performance under different conditions, such as temperature regimes, are necessary to assess their potential as biocontrol agents of P. xylostella. In most studies involving Trichogramma, parasitism rate is the main parameter used to evaluate parasitoid performance, ignoring that parasitoids can cause egg mortality by feeding on the host content and/or to multiple drilling without laying eggs. This study was conducted to investigate three main issues: how temperature affects T. pretiosum and T.atopovirilia development on eggs of P. xylostella, whether or not these species respond differently to temperature, and how important is the mortality they cause besides parasitism on P. xylostella. Temperature effects (from 10 to 30°C) on development, survival, parasitism rate, mortality, and total mortality caused by T. pretiosum and T. atopovirilia on eggs of P. xylostella were evaluated. Temperature affected the development time, female longevity, parasitism rate, mortality not directly related to parasitoid larval development, and total mortality caused on the host. No significant differences were recorded for the estimated thermal requirements for T. pretiosum and T. atopovirilia. However, the higher mortality caused by T. pretiosum indicates that this parasitoid is the most suitable to be used against P. xylostella. Also, the results suggest that the use of parasitism rate as the only parameter to evaluate the performance of T. pretiosum and T. atopovirilia may underestimate the potential of these parasitoids in regulating pest populations.
(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): Cesar A. Marchioro

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

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Plutella xylostella	Cabbage (Brassica oleracea)	Brazil (south)
Trichogramma pretiosum (parasitoid)	Plutella xylostella		Brazil (south)
Trichogramma atopovirilia (parasitoid)	Plutella xylostella		Brazil (south)