The spatio-temporal distribution dynamics of the cabbage seedpod weevil, <i>Ceutorhynchus obstrictus</i> (Coleoptera: Curculionidae), and its larval parasitoids in canola in western Canada

Dosdall, Lloyd M.; Ulmer, Bryan J.; Gibson, Gary A. P.; Cárcamo, H. A.

doi:10.1080/09583150600828320

Cited by 32 publications

(30 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…But the question arises of whether additional releases of European parasitoids are warranted when several species of native natural enemies already attack the weevil. Results reported here and those of Dosdall et al (2006Dosdall et al ( , 2007 indicate that the present parasitoid fauna has sometimes caused substantial levels of parasitism, but current parasitism levels (usually less than 15% for all species combined) are not sufficiently high to adequately control the weevil population. It is not clear whether parasitism levels are still likely to increase over time, since the current situation has shown considerable year-to-year variation (Figs.…”

Section: Discussionmentioning

confidence: 59%

“…When C. obstrictus dispersed to southern Alberta and Saskatchewan it encountered a vast resource of many billions of siliques of B. napus and B. rapa that was largely unexploited by other herbivores and that provided a nutritious, high energy food resource for its larvae where they were protected from surface-dwelling predators. This study and those of Gibson et al (2005Gibson et al ( , 2006a and Dosdall et al (2006) documented a surprisingly diverse fauna of Chalcidoidea species that have responded to the invasion of C. obstrictus, so that these parasitoids have now become, in turn, invasive of canola agroecosystems infested with C. obstrictus larvae. Along with their hosts, a lag period of low parasitoid population densities (Dosdall and Dolinski 2001) was followed by years of increased numbers ), presumably as their populations expanded both numerically and geographically.…”

Section: Discussionmentioning

confidence: 90%

“…Pod samples were taken to the laboratory and placed into cardboard rearing containers, as described by Dosdall et al (2006). Boxes were sealed with tape to prevent escape of C. obstrictus larvae or parasitoids, and were maintained under continuous light at room temperature for six weeks until all parasitoids had emerged.…”

Section: Geographical Distribution and Abundance Of Chalcidoidea Paramentioning

confidence: 99%

“…When meteorological data from 193 sites across Alberta, Saskatchewan, and Manitoba were analyzed with data on the biological requirements of C. obstrictus using the CLIMEX Ò model, it was predicted that the distribution of the species would eventually encompass the entire region of canola production in western Canada (Dosdall et al 2002). However, several species of Chalcidoidea parasitoids were recently found to attack larval populations of the weevil (Gibson et al 2005;Dosdall et al 2006). The current study was undertaken to monitor the distribution and abundance of the cabbage seedpod weevil in western Canada since earlier surveys established its initial dispersal patterns, and to determine its ecological impact on populations of the Chalcidoidea parasitoids.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Responses of Chalcidoidea (Hymenoptera) parasitoids to invasion of the cabbage seedpod weevil (Coleoptera: Curculionidae) in western Canada

et al. 2008

View full text Add to dashboard Cite

Invasion of the European weevil, Ceutorhynchus obstrictus (Marsham), was investigated through surveys of its range and population densities in Alberta and Saskatchewan from 2001 to 2005. After it was first reported in southern Alberta, C. obstrictus rapidly expanded its range and abundance. Our more recent surveys indicate that its northward expansion has slowed, but that it has continued to extend its range eastward to southcentral Saskatchewan. The distribution and abundance of parasitoids of C. obstrictus in Alberta and Saskatchewan were investigated from 2003 to 2005 by mass rearing canola pods infested with C. obstrictus larvae. Although weevil populations were not parasitized for several years immediately following its introduction to southern Alberta, a surprisingly diverse assemblage of Chalcidoidea parasitoids, comprising 12 species from four families, were recently reared from weevil-infested canola siliques in Alberta and Saskatchewan. TheChalcidoidea fauna of C. obstrictus include species with both Nearctic and Holarctic distributions, with some species having restricted host ranges and others that are more niche than taxon-specific. These Chalcidoidea species appear to have expanded their host ranges to parasitize C. obstrictus in the region. Most parasitism is attributable to Trichomalus lucidus (Walker), Chlorocytus sp., and Pteromalus sp. (Pteromalidae), and Necremnus tidius (Walker) (Eulophidae). Parasitism levels varied considerably over the three years of this study. From 2003 to 2005 increases in parasitism occurred among all four of the species dominating the parasitoid fauna of C. obstrictus, but greater increases were observed for Chlorocytus sp. and Pteromalus sp. than for T. lucidus. Parasitoid species have sometimes caused substantial levels of host mortality, although current levels are usually less than 15% for all species combined and so are not sufficient to control weevil populations. Implementing a classical biological control program for C. obstrictus by reconstructing its European natural enemy complex is being considered, but it is still uncertain whether parasitism levels by native Chalcidoidea will increase over time since considerable yearto-year variation has been found. Parasitism levels of C. obstrictus should therefore continue to be monitored to assess whether a classical biological control program should be implemented.

show abstract

Section: Discussionmentioning

confidence: 59%

Section: Discussionmentioning

confidence: 90%

Section: Geographical Distribution and Abundance Of Chalcidoidea Paramentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Responses of Chalcidoidea (Hymenoptera) parasitoids to invasion of the cabbage seedpod weevil (Coleoptera: Curculionidae) in western Canada

et al. 2008

View full text Add to dashboard Cite

show abstract

“…The bowl traps (15-cm diameter, 9-cm depth) followed the design of Dosdall et al (2006). Bowl traps were set in position on 16 June 2005 and 19 June 2007 when the crops were in bud to early flowering (Growth Stage 55 of Thomas 2002), and the traps were adjusted weekly on their anchor posts so they remained at the level of the crop canopy throughout the study.…”

Section: Study Design and Insect Samplingmentioning

confidence: 99%

Leaf nutrient levels and the spatio-temporal distributions of Plutella xylostella and its larval parasitoids Diadegma insulare and Microplitis plutellae in canola

et al. 2009

View full text Add to dashboard Cite

Seasonal distribution patterns of the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), and its principal parasitoids Diadegma insulare (Cresson) (Hymenoptera: Ichneumonidae) and Microplitis plutellae (Muesebeck) (Hymenoptera: Braconidae) were investigated over three site-years in commercial fields of canola (Brassica napus L.) in southern Alberta, Canada. The sampling of P. xylostella, D. insulare, and M. plutellae from points arranged in grid patterns, together with the mapping and analysis of their spatial distributions over time, generated a detailed picture of the pattern of crop infestation by the herbivore and its parasitoids. Plutella xylostella exhibited significant aggregations on different scales most often when its host plants were in early flowering. Diadegma insulare adults exhibited significant aggregated distributions during early flowering and distributions subsequently became more uniform as the wasps moved into the crop later in the season. However, M. plutellae distributions were aggregated in mid flowering in only one site-year. The close spatial associations between densities of D. insulare and P. xylostella indicated that host abundance was the main determinant of parasitoid distribution patterns. Spatial distributions of nutrient contents in leaf tissue and their spatial associations with the herbivore and parasitoids were also investigated. Significant spatial associations existed between certain nutrients (e.g. nitrogen, sulfur, and potassium) and P. xylostella distributions. Sulfur exhibited a positive effect on the distributions of D. insulare but not of M. plutellae. We observed similar relationships between nutrients and the distribution of P. xylostella parasitoids as for nutrients and P. xylostella, but these relationships lacked consistency and may be the results of the spatial associations between the parasitoids and their hosts. Aggregated distributions of adults and larvae of P. xylostella hold promise for spatially targeted insecticidal applications as a means for reducing the environmental impact of insecticides on nontarget and beneficial species in canola agroecosystems.

show abstract

Effects of land use on infestation and parasitism rates of cabbage seed weevil in oilseed rape

Kovács

Kaasik

Lof

et al. 2018

Pest Management Science

View full text Add to dashboard Cite

show abstract

The spatio-temporal distribution dynamics of the cabbage seedpod weevil, Ceutorhynchus obstrictus (Coleoptera: Curculionidae), and its larval parasitoids in canola in western Canada

Cited by 32 publications

References 15 publications

Responses of Chalcidoidea (Hymenoptera) parasitoids to invasion of the cabbage seedpod weevil (Coleoptera: Curculionidae) in western Canada

Responses of Chalcidoidea (Hymenoptera) parasitoids to invasion of the cabbage seedpod weevil (Coleoptera: Curculionidae) in western Canada

Leaf nutrient levels and the spatio-temporal distributions of Plutella xylostella and its larval parasitoids Diadegma insulare and Microplitis plutellae in canola

Effects of land use on infestation and parasitism rates of cabbage seed weevil in oilseed rape

Contact Info

Product

Resources

About