Statistical analysis of outcrossing between adjacent maize grain production fields

Goggi, A. Susana; Caragea, Petruţa C.; López-Sánchez, Higinio; Westgate, Mark E.; Arritt, Raymond W.; Clark, Craig A.

doi:10.1016/j.fcr.2006.04.005

Cited by 53 publications

(57 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Pollen-mediated gene flow has been quantified in detail in several crops using transgenic and marker genes including wheat (Triticum aestivum L.) (Gustafson et al, 2005;Hucl, 1996;Hucl and Matus-Cadiz, 2001;Matus-Cadiz et al, 2007), oilseed rape (B. napus) (Beckie et al, 2003;Damgaard and Kjellsson, 2005;Rieger et al, 2002;Weekes et al, 2005) and maize (Zea mays L.) (Goggi et al, 2006(Goggi et al, , 2007Gustafson et al, 2006;Weekes et al, 2007) (reviewed in Beckie andHall, 2008). Because of differences in research design and source plot size, studies are difficult to compare directly.…”

Section: Discussionmentioning

confidence: 99%

Pollen-mediated gene flow from transgenic safflower (CarthamustinctoriusL.) intended for plant molecular farming to conventional safflower

McPherson

Good

Topinka

et al. 2009

Environ. Biosafety Res.

View full text Add to dashboard Cite

Field experiments were conducted in Chile and western Canada to measure short-distance (0 to 100 m) outcrossing from transgenic safflower (Carthamus tinctorius L.) intended for plant molecular farming to nontransgenic commodity safflower of the same variety. The transgenic safflower used as the pollen source was transformed with a construct for seed-specific expression of a high-value protein and constitutive expression of a gene conferring resistance to the broad-spectrum herbicide glufosinate. Progeny of non-transgenic plants grown in plots adjacent to the transgenic pollen source were screened for glufosinate resistance to measure outcrossing frequency. Outcrossing frequency differed among locations: values closest to the transgenic pollen source (0 to 3 m) ranged from 0.48 to 1.67% and rapidly declined to between 0.0024 to 0.03% at distances of 50 to 100 m. At each location, outcrossing frequency was spatially heterogeneous, indicating insects or wind moved pollen asymmetrically. A power analysis assuming a binomial distribution and a range of alpha values (type 1 error) was conducted to estimate an upper and lower confidence interval for the probable transgenic seed frequency in each sample. This facilitated interpretation when large numbers of seeds were screened from the outcrossing experiments and no transgenic seeds were found. This study should aid regulators and the plant molecular farming industry in developing confinement strategies to mitigate pollen mediated gene flow from transgenic to non-transgenic safflower.

show abstract

Section: Discussionmentioning

confidence: 99%

Pollen-mediated gene flow from transgenic safflower (CarthamustinctoriusL.) intended for plant molecular farming to conventional safflower

McPherson

Good

Topinka

et al. 2009

Environ. Biosafety Res.

View full text Add to dashboard Cite

show abstract

“…In practice, shorter isolation distances than those currently proposed by several member states would often be sufficient to ensure compliance with labelling requirements. Cross-fertilisation studies mimicking worst-case commercial on-farm situations demonstrated that isolation distances exceeding 50 m are not always necessary to comply with the labelling threshold of 0.9% in grain maize (Goggi et al, 2006;Gustafson et al, 2006;Pla et al, 2006;Bannert and Stamp, 2007;Kraic et al, 2007;van de Wiel et al, 2007;Weber et al, 2007;Weekes et al, 2007;Della Porta et al, 2008). Similar conclusions have been drawn from out-crossing studies performed under real agricultural situations in Spain and from predictive vertical gene flow modelling at the landscape level in France (Messéan et al, 2006;Lécroart et al, 2007) and Italy (Mazzoncini et al, 2007).…”

Section: Science-based Principlementioning

confidence: 99%

Coexistence of genetically modified (GM) and non-GM crops in the European Union. A review

Devos

Demont

Dillen

et al. 2009

Agron. Sustain. Dev.

165

127

View full text Add to dashboard Cite

-The adoption of genetically modified (GM) crops in the European Union (EU) raises questions on the feasibility of coexistence between GM and non-GM crops. Regulations to ensure that different cropping systems can develop side-by-side without excluding any agricultural option are currently implemented or developed by member states. The aim of this review is to explore whether nationally or regionally proposed coexistence strategies comply with the general principles established by the European Commission that ask for science-based and proportionate coexistence measures. In the first part, existing legal requirements and potential sources of adventitious mixing are reviewed. It is discussed what type of coexistence measures might be necessary to keep GM inputs below the legal tolerance threshold of 0.9%. Concentrating on cross-fertilisation as the major biological source of adventitious mixing in maize, it is then assessed to which extent available scientific data on cross-fertilisation can explain the diversity of currently proposed isolation distances by several member states. In the second part, it is analysed whether currently proposed isolation distances reflect contending policy objectives towards GM crops that largely exceed the economic scope of coexistence. It is investigated how coexistence is intersecting with a wider debate about the role of GM crops in agriculture. Based on the analysis of existing cross-fertilisation data, it is concluded that some of the currently proposed isolation distances are not in line with the coexistence principles laid down by the European Commission: they are (i) excessive from a scientific point of view; (ii) difficult to implement in practice; (iii) rarely proportional to the regional heterogeneity in the agricultural landscape; and (iv) not proportional to the farmers' basic economic incentives for coexistence. Hence, the range of proposed isolation distances cannot simply be explained by different interpretations of available scientific data, possible error intervals and remaining uncertainties inherent in the scientific process. It is argued that other than scientific issues must be at play. One might thus claim that coexistence has become an arena of contending values and visions on the future of agriculture and on the role GM crops might play therein.adventitious mixing / Bt-maize / coexistence / cross-fertilisation / flexible measures / genetically modified (GM) crops / isolation distances / liability / fixed measures / sustainable development

show abstract

“…However, defining the appropriate isolation perimeter width is complicated: various biological, physical, experimental and analytical factors with varying levels of importance play a role in the study of cross-fertilisation in maize (Devos et al, 2005). To take the factors that are relevant for co-existence into account, recent empirical crossfertilisation studies mimic worst-case commercial on-farm situations (Halsey et al, 2005;Della Porta et al, 2006;Goggi et al, 2006;Pla et al, 2006;Weber et al, 2007;Weekes et al, 2007). In Spain, out-crossing studies are even performed in real agricultural situations of co-existence.…”

Section: Eu Countries Eventsmentioning

confidence: 99%

Implementing isolation perimeters around genetically modified maize fields

Devos¹,

Reheul²,

Thas³

et al. 2007

Agron. Sustain. Dev.

View full text Add to dashboard Cite

-Due to the growing cultivation area of genetically modified (GM) maize and the rising number of GM maize varieties commercially available to European farmers, the co-existence between GM and non-GM maize is becoming a burning issue in some European regions. Hence, Member States are imposing or discussing specific co-existence measures to keep the adventitious presence of GM material in non-GM produces below the established labelling threshold. As maize is a cross-pollinated crop that uses wind for the dispersal of its pollen, on-farm co-existence measures may rely on the spatial isolation of GM and non-GM maize fields. In this study, we developed an approach that combines geographic information system (GIS) datasets with Monte Carlo simulations to assess the feasibility of implementing isolation perimeters around GM maize fields, since its practical implementation is rarely addressed in the co-existence debate. More specifically, five scenarios differing in shares and spatial distributions of GM maize were tested for various isolation perimeters in two agricultural areas in Flanders (Belgium). The GIS analyses emphasised the small size of maize fields and their scattered distribution throughout the cropped area. The feasibility of implementing isolation perimeters was largely affected by the (GM) maize share, the spatial distribution of GM maize, and the width of isolation perimeters. The higher the (GM) maize share and the wider the isolation perimeter, the higher the proportions of farmers with non-GM maize fields occurring within the implemented isolation perimeter. Compared with randomly distributed GM maize fields, the clustering of GM maize fields on a larger scale and at the farm level increased the feasibility of implementing isolation perimeters. The approach developed proved to be a valuable tool to quantify the feasibility of implementing isolation perimeters under real agricultural conditions. adventitious mixing / co-existence / cross-fertilisation / genetically modified crops / geographic information system / isolation perimeters / pollen flow / regional variation / simulations

show abstract

Statistical analysis of outcrossing between adjacent maize grain production fields

Cited by 53 publications

References 18 publications

Pollen-mediated gene flow from transgenic safflower (CarthamustinctoriusL.) intended for plant molecular farming to conventional safflower

Pollen-mediated gene flow from transgenic safflower (CarthamustinctoriusL.) intended for plant molecular farming to conventional safflower

Coexistence of genetically modified (GM) and non-GM crops in the European Union. A review

Implementing isolation perimeters around genetically modified maize fields

Contact Info

Product

Resources

About