Predicting Spring Moth Emergence in the Pink Bollworm (Lepidoptera: Gelechiidae): Implications for Managing Resistance to Transgenic Cotton

Carrière, Yves; Ellers-Kirk, Christa; Pedersen, Brent S.; Haller, Shirley; Antilla, Larry

doi:10.1603/0022-0493-94.5.1012

Cited by 20 publications

(20 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Symbols represent average population density for two simulations. Filled circles: F ϭ 8, e ϭ 0.1; open circles: F ϭ 8, e ϭ 0.9; filled triangles: F ϭ 12, e ϭ 0.1; open triangles: F ϭ 12, e ϭ 0.9. than 1,100 pheromone traps were set near cotton fields each year across the 15 regions (12,13). Trapping started after an accumulation of 500 heat units.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Long-term regional suppression of pink bollworm byBacillus thuringiensiscotton

Carrière

Ellers-Kirk

Sisterson

et al. 2003

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

303

175

View full text Add to dashboard Cite

Despite the potentially profound impact of genetically modified crops on agriculture and the environment, we know little about their long-term effects. Transgenic crops that produce toxins from Bacillus thuringiensis (Bt) to control insects are grown widely, but rapid evolution of resistance by pests could nullify their benefits. Here, we present theoretical analyses showing that long-term suppression of pest populations is governed by interactions among reproductive rate, dispersal propensity, and regional abundance of a Bt crop. Supporting this theory, a 10-year study in 15 regions across Arizona shows that Bt cotton suppressed a major pest, pink bollworm (Pectinophora gossypiella), independent of demographic effects of weather and variation among regions. Pink bollworm population density declined only in regions where Bt cotton was abundant. Such long-term suppression has not been observed with insecticide sprays, showing that transgenic crops open new avenues for pest control. The debate about putative benefits of Bt crops has focused primarily on short-term decreases in insecticide use. The present findings suggest that long-term regional pest suppression after deployment of Bt crops may also contribute to reducing the need for insecticide sprays.G enetically engineered crops have quickly become a significant component of agriculture, but little is known about their long-term consequences. Transgenic cultivars of cotton and maize that produce toxins from Bacillus thuringiensis (Bt) to control insect pests were grown on 12 million hectares worldwide during 2001 (1). A major concern is that rapid evolution of resistance by pests could nullify the benefits of Bt crops (2-6). It has also been proposed, however, that Bt crops imposing high mortality could cause regional suppression of target pests before resistance occurs (6-9). This would be most likely for target pests with a narrow host range, because their diet would be affected most by Bt crops. Here we report results of a large-scale 10-year study revealing that extensive use of Bt cotton in Arizona caused regional suppression of pink bollworm (Pectinophora gossypiella), an ecological specialist on cotton (10).Pink bollworm moths emerge in the spring, and four to five generations are completed before winter diapause begins (10). Population growth is exponential in non-Bt cotton fields where the pink bollworm is virtually always present. Survival of pink bollworm larvae is Ͻ0.5% in Bt cotton fields (3). We hypothesized that regional declines in pink bollworm density would occur because deployment of Bt cotton reduces the number of source habitats (non-Bt cotton fields) and the net reproductive rate of migrants from source habitats. Accordingly, we expected a density decline in regions where a threshold use of Bt cotton was exceeded (Fig. 1). To test this hypothesis, we evaluated changes in pink bollworm population density related to abundance of Bt cotton in each of 15 cotton-growing regions in Arizona during the 5 years before and the 5 years after deploym...

show abstract

Section: Methodsmentioning

confidence: 99%

“…Trapping started after an accumulation of 500 heat units. Cumulative trap catch up to an accumulation of 1,900 heat units was used to estimate density of the first overwintering generation (13). For each region and year, traps that had more than three missing records were excluded.…”

Section: Methodsmentioning

confidence: 99%

Long-term regional suppression of pink bollworm byBacillus thuringiensiscotton

Carrière

Ellers-Kirk

Sisterson

et al. 2003

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

303

175

View full text Add to dashboard Cite

show abstract

“…In this way, the open‐refuge technique can be highly effective when the dose is high and the resistant allele is completely recessive. Reports of extinction in the HDR modeling literature exist – see Carrière et al. 2001– but are scarce.…”

Section: How Refuges Work or Fail Tomentioning

confidence: 99%

Analysis of sustainable pest control using a pesticide and a screened refuge

Ringland¹,

George²

2010

Evolutionary Applications

View full text Add to dashboard Cite

We describe and analyze a ‘screened refuge’ technique for indefinitely sustaining control of insect pests using transgenic pesticidal crops or an applied pesticide, even when resistance is not recessive. The screen is a physical barrier that restricts pest movement. In a deterministic discrete-time model of the use of this technique, we obtain asymptotic analytical formulas for the two important equilibria of the system in terms of the refuge size and the pest fitnesses, mutation rates, and mobility out of and into the refuge. One of the equilibria is stable and is the point at which the pest population is controlled. The other is a saddle whose stable manifold bounds the basin of attraction of the former: its location provides a measure of the tolerance of the control mechanism to perturbations in the resistant allele density.

show abstract

“…Trapping was conducted in the spring up to an accumulation of 1900 heat units (April through June), which covered emergence of ϳ97% of adults from the first generation (Carrière et al 2001b). Heat-unit accumulation was evaluated with the single sine-curve method, using a starting date of 1 January and a lower and upper pink bollworm developmental threshold of 12.8ЊC and 30ЊC, respectively.…”

Section: Pheromone Trappingmentioning

confidence: 99%

SOURCES, SINKS, AND THE ZONE OF INFLUENCE OF REFUGES FOR MANAGING INSECT RESISTANCE TO Bt CROPS

Carrière

Dutilleul

Ellers-Kirk

et al. 2004

Ecological Applications

Self Cite

View full text Add to dashboard Cite

The refuge strategy is central for delaying insect resistance to transgenic crops that produce Bacillus thuringiensis (Bt) toxins, but determining an effective spatial configuration of refuges has been problematic. We developed a spatially explicit, demographically based method for estimating the zone of influence of refuges, the area over which refuges increase an insect's population density. The method relied on global positioning system (GPS) and geographic information system (GIS) technologies combined with spatial statistics. We applied it in two successive years to Arizona populations of pink bollworm, a major cotton pest. Refuges at 0.75 km or less from Bt cotton had the greatest potential for delaying resistance in both years studied. However, the zone of influence of refuges varied between years and among sites. The density of susceptible moths was significantly lower at sites with high compared to low abundance of Bt cotton relative to non-Bt cotton. Thus, abundance of a Bt crop relative to a non-Bt crop may influence the effectiveness of refuges. Our spatially explicit approach takes such source-sink dynamics into account and hence is well suited to help determine how refuges should be deployed.

show abstract

Predicting Spring Moth Emergence in the Pink Bollworm (Lepidoptera: Gelechiidae): Implications for Managing Resistance to Transgenic Cotton

Cited by 20 publications

References 29 publications

Long-term regional suppression of pink bollworm byBacillus thuringiensiscotton

Long-term regional suppression of pink bollworm byBacillus thuringiensiscotton

Analysis of sustainable pest control using a pesticide and a screened refuge

SOURCES, SINKS, AND THE ZONE OF INFLUENCE OF REFUGES FOR MANAGING INSECT RESISTANCE TO Bt CROPS

Contact Info

Product

Resources

About