- Jeffrey A. Harvey (1)
- Marcel Dicke (1)
- Louise E.M. Vet (1)
- Jetske G. Boer de (1)
- Joop J.A. Loon van (1)
- Lisa J.M. Heumen van (1)
- Martine Kos (1)
- Jenny Lazebnik (1)
- Thibault P.M. Costaz (1)
- Lucia Salis (1)
- Marianne Tibboel (1)
- Ward Tollenaar (1)
Effects of temperature and food source on reproduction and longevity of aphid hyperparasitoids of the genera Dendrocerus and Asaphes
Boer, Jetske G. de; Salis, Lucia ; Tollenaar, Ward ; Heumen, Lisa J.M. van; Costaz, Thibault P.M. ; Harvey, Jeffrey A. ; Kos, Martine ; Vet, Louise E.M. - \ 2019
BioControl 64 (2019)3. - ISSN 1386-6141 - p. 277 - 290.
Aphidius colemani - Fourth trophic level - Hymenoptera - Megaspilidae - Myzus persicae - Pteromalidae
Hyperparasitoids of aphid parasitoids commonly occur in (sweet pepper) greenhouses, and can pose a threat to effective biological control of aphids. Here, we studied life history characteristics of laboratory colonies of Dendrocerus spp. Ratzeburg (Hymenoptera: Megaspilidae) and Asaphes spp. Walker (Pteromalidae) that originated from a commercial sweet pepper greenhouse. We aimed to clarify how these two hyperparasitoid taxa can coexist inside greenhouses. Hyperparasitoids of both taxa have a long lifespan that was extended significantly by food sources that are naturally available in a greenhouse environment, including aphid honeydew and sweet pepper flowers. Differences in sensitivity to decreased or increased temperatures did not appear to explain seasonal patterns in abundance of Dendrocerus spp. and Asaphes spp. in sweet pepper greenhouses. Instead, Dendrocerus spp. may have an advantage early in the season because it thrives on aphid honeydew, while Asaphes spp. may do better later in the season because of its long lifespan and extensive reproductive period.
Inoculation of susceptible and resistant potato plants with the late blight pathogen Phytophthora infestans : effects on an aphid and its parasitoid
Lazebnik, Jenny ; Tibboel, Marianne ; Dicke, Marcel ; Loon, Joop J.A. van - \ 2017
Entomologia Experimentalis et Applicata 163 (2017)3. - ISSN 0013-8703 - p. 305 - 314.
Aphididae - Aphidius colemani - Braconidae - genetic modification - Hemiptera - Hymenoptera - Myzus persicae - non-target effects - plant-pathogen-insect interactions - plant–insect interactions - Solanum tuberosum - trophic interactions
Plants are exposed to microbial pathogens as well as herbivorous insects and their natural enemies. Here, we examined the effects of inoculation of potato plants, Solanum tuberosum L. (Solanaceae), with the late blight pathogen Phytophthora infestans (Mont.) de Bary (Peronosporales: Pythiaceae) on an aphid species commonly infesting potato crops and one of the aphid's major parasitoids. We observed the peach-potato aphid, Myzus persicae Sulzer (Hemiptera: Aphididae), and its natural enemy, the biocontrol agent Aphidius colemani Viereck (Hymenoptera: Braconidae), on potato either inoculated with water or P. infestans. Population growth of the aphid, parasitism rate of its natural enemy, and other insect life-history traits were compared on several potato genotypes, the susceptible cultivar Désirée and genetically modified (GM) isogenic lines carrying genes conferring resistance to P. infestans. Effects of P. infestans inoculation on the intrinsic rate of aphid population increase and the performance of the parasitoid were only found on the susceptible cultivar. Insect traits were similar when comparing inoculated with non-inoculated resistant GM genotypes. We also tested how GM-plant characteristics such as location of gene insertion and number of R genes could influence non-target insects by comparing insect performance among GM events. Different transformation events leading to different positions of R-gene insertion in the genome influenced aphids either with or without P. infestans infection, whereas effects of position of R-gene insertion on the parasitoid A. colemani were evident only in the presence of inoculation with P. infestans. We conclude that it is important to study different transformation events before continuing with further stages of risk assessment of this GM crop. This provides important information on the effects of plant resistance to a phytopathogen on non-target insects at various trophic levels.