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A meta-analysis of effects of Bt crops on honey bees (Hymenoptera: Apidae).

Duan JJ, Marvier M, Huesing J, Dively G, Huang ZY - PLoS ONE (2008)

Bottom Line: We conducted a meta-analysis of 25 studies that independently assessed potential effects of Bt Cry proteins on honey bee survival (or mortality).Our results show that Bt Cry proteins used in genetically modified crops commercialized for control of lepidopteran and coleopteran pests do not negatively affect the survival of either honey bee larvae or adults in laboratory settings.Although the additional stresses that honey bees face in the field could, in principle, modify their susceptibility to Cry proteins or lead to indirect effects, our findings support safety assessments that have not detected any direct negative effects of Bt crops for this vital insect pollinator.

View Article: PubMed Central - PubMed

Affiliation: Ecological Technology Center, Monsanto Company, St. Louis, Missouri, USA.

ABSTRACT

Background: Honey bees (Apis mellifera L.) are the most important pollinators of many agricultural crops worldwide and are a key test species used in the tiered safety assessment of genetically engineered insect-resistant crops. There is concern that widespread planting of these transgenic crops could harm honey bee populations.

Methodology/principal findings: We conducted a meta-analysis of 25 studies that independently assessed potential effects of Bt Cry proteins on honey bee survival (or mortality). Our results show that Bt Cry proteins used in genetically modified crops commercialized for control of lepidopteran and coleopteran pests do not negatively affect the survival of either honey bee larvae or adults in laboratory settings.

Conclusions/significance: Although the additional stresses that honey bees face in the field could, in principle, modify their susceptibility to Cry proteins or lead to indirect effects, our findings support safety assessments that have not detected any direct negative effects of Bt crops for this vital insect pollinator.

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Related in: MedlinePlus

Meta-analysis of studies that report survival of honey bees exposed to Bt Cry proteins or plant tissues (pollen) that are active against lepidopterans and coleopterans.Effect size is Hedge's d, and error bars represent bias-corrected bootstrap 95% confidence intervals. Positive mean effect sizes indicate improved survival when exposed to Cry proteins compared to water or sugar-water control treatments. N = number of lines of independent data summarized by each bar.
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pone-0001415-g001: Meta-analysis of studies that report survival of honey bees exposed to Bt Cry proteins or plant tissues (pollen) that are active against lepidopterans and coleopterans.Effect size is Hedge's d, and error bars represent bias-corrected bootstrap 95% confidence intervals. Positive mean effect sizes indicate improved survival when exposed to Cry proteins compared to water or sugar-water control treatments. N = number of lines of independent data summarized by each bar.

Mentions: When all studies were combined, no statistically significant effect of Bt Cry protein treatments on survival of honey bees was detected (N = 39, d = 0.025, 95% CI = −0.128 to 0.171). When data for lepidopteran-active and coleopteran-active Bt Cry proteins were compared using a fixed categorical meta-analysis model, the above pattern of no significant effects held true for each class of protein (Fig. 1). No significant difference in effect sizes was detected between lepidopteran-active and coleopteran-active proteins (Q = 0.668, df = 1, P = 0.25); nor was any significant within-group heterogeneity detected for effect sizes calculated for either lepidopteran-active (Qw = 12.828, df = 29, P>0.99) or coleopteran-active proteins (Qw = 5.893, df = 8, P = 0.66). Mean effect sizes also did not differ (Q = 0.012, df = 1, P = 0.90) between studies that were peer-reviewed (N = 20, d = 0.015, 95% CI = −0.153 to 0.245) versus not peer-reviewed (N = 19, d = 0.039, 95% CI = −0.190 to 0.293).


A meta-analysis of effects of Bt crops on honey bees (Hymenoptera: Apidae).

Duan JJ, Marvier M, Huesing J, Dively G, Huang ZY - PLoS ONE (2008)

Meta-analysis of studies that report survival of honey bees exposed to Bt Cry proteins or plant tissues (pollen) that are active against lepidopterans and coleopterans.Effect size is Hedge's d, and error bars represent bias-corrected bootstrap 95% confidence intervals. Positive mean effect sizes indicate improved survival when exposed to Cry proteins compared to water or sugar-water control treatments. N = number of lines of independent data summarized by each bar.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2169303&req=5

pone-0001415-g001: Meta-analysis of studies that report survival of honey bees exposed to Bt Cry proteins or plant tissues (pollen) that are active against lepidopterans and coleopterans.Effect size is Hedge's d, and error bars represent bias-corrected bootstrap 95% confidence intervals. Positive mean effect sizes indicate improved survival when exposed to Cry proteins compared to water or sugar-water control treatments. N = number of lines of independent data summarized by each bar.
Mentions: When all studies were combined, no statistically significant effect of Bt Cry protein treatments on survival of honey bees was detected (N = 39, d = 0.025, 95% CI = −0.128 to 0.171). When data for lepidopteran-active and coleopteran-active Bt Cry proteins were compared using a fixed categorical meta-analysis model, the above pattern of no significant effects held true for each class of protein (Fig. 1). No significant difference in effect sizes was detected between lepidopteran-active and coleopteran-active proteins (Q = 0.668, df = 1, P = 0.25); nor was any significant within-group heterogeneity detected for effect sizes calculated for either lepidopteran-active (Qw = 12.828, df = 29, P>0.99) or coleopteran-active proteins (Qw = 5.893, df = 8, P = 0.66). Mean effect sizes also did not differ (Q = 0.012, df = 1, P = 0.90) between studies that were peer-reviewed (N = 20, d = 0.015, 95% CI = −0.153 to 0.245) versus not peer-reviewed (N = 19, d = 0.039, 95% CI = −0.190 to 0.293).

Bottom Line: We conducted a meta-analysis of 25 studies that independently assessed potential effects of Bt Cry proteins on honey bee survival (or mortality).Our results show that Bt Cry proteins used in genetically modified crops commercialized for control of lepidopteran and coleopteran pests do not negatively affect the survival of either honey bee larvae or adults in laboratory settings.Although the additional stresses that honey bees face in the field could, in principle, modify their susceptibility to Cry proteins or lead to indirect effects, our findings support safety assessments that have not detected any direct negative effects of Bt crops for this vital insect pollinator.

View Article: PubMed Central - PubMed

Affiliation: Ecological Technology Center, Monsanto Company, St. Louis, Missouri, USA.

ABSTRACT

Background: Honey bees (Apis mellifera L.) are the most important pollinators of many agricultural crops worldwide and are a key test species used in the tiered safety assessment of genetically engineered insect-resistant crops. There is concern that widespread planting of these transgenic crops could harm honey bee populations.

Methodology/principal findings: We conducted a meta-analysis of 25 studies that independently assessed potential effects of Bt Cry proteins on honey bee survival (or mortality). Our results show that Bt Cry proteins used in genetically modified crops commercialized for control of lepidopteran and coleopteran pests do not negatively affect the survival of either honey bee larvae or adults in laboratory settings.

Conclusions/significance: Although the additional stresses that honey bees face in the field could, in principle, modify their susceptibility to Cry proteins or lead to indirect effects, our findings support safety assessments that have not detected any direct negative effects of Bt crops for this vital insect pollinator.

Show MeSH
Related in: MedlinePlus