Supplementary data: Scientific littterature on Bt plants in 2008 and 2009 (ended 30 April 2009)

Field / Reference / Experimental conditions / Summary / comments
Agronomy
General / Author: Achon MA, Alonso-Dueñas N,
Year: 2008.
Title: * Impact of 9 years of Bt-maize cultivation on the distribution of maize viruses.
Journal: Transgenic Research Published on line 9 dec. 2008 / Mon810 among others
Field / This study assesses the effect of Bt-maize on the distribution of maize viruses. Random surveys were conducted in Spain between 2001 and 2006 to evaluate the occurrence of maize viruses in Bt-maize cultivation areas and in areas where this crop had not been introduced. Maize dwarf mosaic virus (MDMV) was the predominant virus in Bt-areas, and Maize rough dwarf virus (MRDV) was the most predominant one in non-Bt-areas, with MRDV an emergent virus in both types of areas. A decline in the occurrence of MDMV and an increase in that of Sugarcane mosaic virus was observed in Bt-areas. Additionally, data obtained over 6 years in experimental fields showed non-significant differences between the infection rates exhibited by two generations of Bt varieties and the non-transformed isogenics varieties for any of the viruses. Our data suggest that differences in virus distribution are linked to the genetic background of the maize varieties and the distribution of virus reservoirs rather than to Bt-maize cultivation.

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From: CropBiotech Update 16 January 2009
Impact Of Bt Maize Cultivation On Maize Virus Distribution
Genetically modified, insect resistant maize was first cultivated in Spain in 1998. GM maize growing areas reached 64,200 ha in 2006, with 85 percent of the transgenic maize crop originating in the northeastern region of the country. Spain is the largest GM maize producer in the European Union. Bt-maize has proved to be an excellent means to control corn borers. Increased densities of aphids and leafhoppers, however, have been recorded in some Bt-maize fields. These non-target arthropods are vectors of viruses infecting the crop. In a study published by Transgenic Research, researchers from the University of Lleida evaluated the changes in the distribution and abundance of maize viruses in Spain after 9 years of large-scale cultivation of Bt-maize.
The maize dwarf mosaic virus (MDMV) was found to be the predominant virus in Bt-areas, and maize rough dwarf virus (MRDV) was found to be common in non-Bt-areas, with MRDV an emergent virus in both types of areas. Data obtained from 2001 to 2006 in experimental fields showed non-significant differences between the infection rates exhibited by two generations of Bt varieties and the non-transformed isogenics varieties for any of the viruses. The researchers concluded that differences in virus distribution are linked to the genetic background of the maize varieties and the distribution of virus reservoirs rather than to Bt-maize cultivation.
Author: Adamczyk JJ Jr, J. S. Mahaffey
Year: 2008
Title: * Efficacy of Vip3A and Cry1Ab Transgenic Traits in cottoN against Various Lepidopteran Pests.
Journal: Florida Entomologist 91(4): 570-575 / Cry1A and/or
Vip3A
Field / From 2004 through 2005, plots of experimental transgenic cotton lines containing the vegetative insecticidal protein, Vip3A; -endotoxin, Cry1Ab; and both Vip3A and Cry1Ab were evaluated for efficacy against certain lepidopteran pests. Results showed that the cotton line containing Vip3A was more efficacious against the beet Spodoptera exigua (Hubner) and fall armyworm Spodoptera frugiperda (J. E. Smith) compared to the Cry1Ab cotton line; however, the Cry1Ab cotton line was more efficacious against the tobacco budworm Heliothis virescens F. compared to the cotton line containing Vip3A. Both the Vip3A and Cry1Ab cotton lines provided similar mortality against the bollworm Helicoverpa zea (Boddie). No synergism between Vip3A and Cry1Ab was observed.

Author: Beltagi MS
Year: 2008.
Title: * Molecular Responses of Bt Transgenic Corn (zea Mays L.) Plans to Salt (nacl) Stress.
Journal: Australian Journal of Crop Science 2(2): 57-63. / Cry1Ab (Mon810) and HeTo
Laboratory / Non-transformed and Bt transgenic crop lines of a hybrid (YieldGard 2) corn (Zea mays L.) plants in the 4th leaf stage were subjected to 0, 50, 100 and 150 mM NaCl. Significant (P _ 0.05) reduction in growth of non-traformed plants was recorded under almost all levels (50, 100 and 150 mM) of salt (NaCl) stress; while, the growth of the Bt transgenic corn plants showed no significant changes under the same levels of salt stress. Chlorophyll a contents were reduced at 150 mM NaCl only; but did not change in the BT transgenic corn plants. Chlorophyll b was not responsive to NaCl treatments in both non-transformed and Bt transgenic corn plants. Chlorophyll stability index (CSI) were always higher in the Bt transgenic than in the non-transformed corn plants under all salinity levels. The analyses of SDS-PAGE revealed relative stability in the patterns of protein bands in the Bt transgenic corn plants under salinity stress. The sum of optical densities of protein bands was higher in the Bt transgenic corn plants. In response to salinity stress, a group of polypeptide (76.96, 59.38, 41.56, 33.5 and 31.26 KDa) were newly synthesized in both non-transformed and Bt transgenic plants. Salt susceptible polypeptides of molecular weights 325.47, 32.64 and 24.17 KDa were found only in non-transformed corn plants and completely disappeared under all level of salt stress; while two polypeptides of molecular weights 38.59 and 30.61 KDa were totally inhibited in all salt-stressed corn plants. The synthesis of another four polypeptides (298.81, 99.82, 20.79 and 19.43 KDa) was solely specific to the Bt transgenic corn plants. Stability of chlorophyll pigments and molecular weights of salt stress responsive proteins are key genetic determinants of salt stress in Bt transgenic corn plants.

Author: Bohanec M, Messean, A.; Scatasta, S.; Angevin, F.; Griffiths, B.; Krogh, P. H.; Znidarsic, M.; Dzeroski, S
Year: 2008
Title: * A qualitative multi-attribute model for economic and ecological assessment of genetically modified crops.
Journal: Ecological Modelling 215 (1/3) 247-261 / Maize
Bt & Ht / Genetically modified (GM) crops have become a real option in modern agriculture. They offer advantages for agricultural production, but they also raise concerns about their ecological and economic impacts. Decisions about GM crops are complex and call for decision support. This paper presents a qualitative multi-attribute model for the assessment of ecological and economic impacts at a farm-level of GM and non-GM maize crops. The model is applied for one agricultural season. This is an ex-ante model developed according to DEX methodology. In this model, cropping systems are defined by four groups of features: (1) crop sub-type, (2) regional and farm-level context, (3) crop protection and crop management strategies, and (4) expected characteristics of the harvest. The impact assessment of cropping systems is based on four groups of ecological and two groups of economic indicators: biodiversity, soil biodiversity, water quality, greenhouse gasses, variable costs and production value. The evaluation of cropping systems is governed by expert-defined rules. The paper describes the structure and components of the model, and presents three practical applications of the model, assessing both hypothetical and real-life cropping systems. In an overall assessment of the ecological and economic outcomes the model ranked cropping systems in the order: organically managed > GM systems including Bt and HT traits > conventionally managed maize. The paper discusses contributions of the model to decision-making practice and highlights methodological lessons learned during its development.

Author: Brookes G
Year: 2008
Title: * The impact of using GM insect resistant maize in Europe since 1998
Journal: Int. J. Biotechnology, 10, Nos. 2/3, 148–166 - [Special Issue: The economics of agricultural biotechnology.] / Maize Bt (mainly Mon810)
Review / Genetically Modified (GM) insect resistant (Bt) maize crops have been grown commercially in the European Union (EU) since 1998, and in 2006, there were plantings in seven EU member states. This paper reviews the specific economic impacts on yield and farm income as well as the environmental impact in respect of insecticide usage (where data exists). The analysis shows that there have been important yield and net economic benefits at the farm level equal to an improvement in profitability of between 12 and 21%. Where farmers have previously used insecticides to control pests, the technology has reduced insecticide spraying and as a result decreased the associated environmental impact. Bt maize has also delivered important improvements in grain quality through significant reductions in the levels of mycotoxins found in the grain.

Author: Brookes G, Barfoot P
Title: Global impact of biothech crops: socio-economic and environmental effects 1996–2006.
Year: 2008
Journal: AgBioForum 11:21–38. / Maize Bt among others
Review / Genetically modified (GM) crops have been grown commercially on a substantial scale for eleven years. This paper updates the assessment of the impact this technology is having on global agriculture from both economic and environmental perspectives. It examines specific global economic impacts on farm income and environmental impacts associated with pesticide usage and greenhouse gas (GHG) emissions for each of the countries where GM crops have been grown since 1996. The analysis shows that there have been substantial net economic benefits at the farm level amounting to $6.94 billion in 2006 and $33.8 billion for the eleven-year period (in nominal terms). The technology has reduced pesticide spraying by 286 million kg and, as a result, decreased the environmental impact associated with herbicide and insecticide use on these crops by 15.4%. GM technology has also significantly reduced the release of GHG emissions from this cropping area, which, in 2006, was equivalent to removing 6.56 million cars from the roads.

Author: Cullen E
Year: 2008
Title: ** Rootworm Bt Corn and Soil Insecticides – One or the other, but not both
Journal: Wisconsin Crop Manager, 14, 7: 44-45. / Cry3, Cry34 and Cry35
Field / This article stems from our discussion about this proposed practice to “double-up” on rootworm control tactics for the 2007 season. We (UW Madison Entomology and UW-Extension) do not recommend this practice, nor does it fit into a sound integrated pest management (IPM) approach to agronomic field crop production.

Author: Eichenseer H, Strohbehn R; Burks JC
Year: 2008
Title: * Frequency and Severity of Western Bean Cutworm (Lepidoptera: Noctuidae) Ear Damage in Transgenic Corn Hybrids Expressing Different Bacillus thuringiensis Cry Toxins
Journal: Journal of Economic Entomology 101, 2 (9): 555-563 / Cry1F
Laboratory &
Fields / The frequency and severity of corn ear damage caused by western bean cutworm, Striacosta albicosta (Smith), were measured on transgenic corn, Zea mays L., hybrids expressing two different insecticidal Bacillus thuringiensis (Bt) (Berliner) Cry toxins (Bt) selected to protect against damage caused by larval European corn borer, Ostrinia nubilalis (Hübner). A field cage experiment deliberately infested with western bean cutworm egg masses resulted in less damage in the hybrid expressing the Cry1F protein and supported fewer western bean cutworm larvae than its non-Bt isoline. Corn hybrids expressing Cry1F, grown in small plot field experiments at three locations over two separate years and exposed to natural western bean cutworm infestations suffered less damage than non-Bt or Bt-hybrids expressing a Cry1Ab protein. Later maturing hybrids suffered more damage than shorter-season hybrids. Finally, corn ears observed in strip trials for several years in diverse agronomic conditions in farmer-cooperator fields corroborated the in-plant protection conferred by corn hybrids expressing the Cry1F protein in small plot field trials.

Author: Felke M, Langenbruch, G. A.
Year: 2008
Title: * Susceptibility of European corn borer larvae to pollen of B.t.-176 maize. [Original Title: Empfindlichkeit von Maiszunslerlarven gegenuber B.t.-176 Maispollen.]
Journal: Nachrichtenblatt des Deutschen Pflanzenschutzdienstes 60 (1): 2-6 / Bt176
(Cry1Ab+PAT)
Field / The sensitivity of European corn borer larvae (Ostrinia nubilalis) (second instar) on pollen of B.t.-176 maize was tested during the research project "Impact of pollen from transgenic B.t.-maize on non-target-lepidopterans" that was financially supported by the Federal Ministry of Education and Research (BMBF) and the Federal Environment Agency (UBA). Bioassays were set up as no choice tests and larvae were fed with defined amounts of pollen from the transgenic cultivar B.t.-176 (PACTOL CB), which expresses the Cry1Ab delta endotoxin, as well as the conventional isogenic cultivar PACTOL. After one week, larval weight gain and mortality were recorded. Mortality of the tested European corn borer larvae increased with increasing pollen numbers, indicating a clear dose-response relationship. Application of even 10 pollen grains of B.t.-176 maize per larva led to an increased mortality rate of 28 +- 10.2% compared to the untreated control (10.31 +- 2.41%). Mortality between B.t.-176 variants and untreated control differed significantly if 20 (mortality rate=59.56 +- 12.07%) or more pollen grains per larva were applied. The highest pollen dose tested (160 pollen grains per individual) caused a mortality rate of 80 +- 8.37%. Weight gain of larvae fed with pollen from B.t.-176 maize was lower compared to the untreated control, but differences were not significant. Ingestion of conventional maize pollen did not have positive nor negative effects on survival or development of the larvae. The LC50-value was calculated with 32.43 B.t.-176 maize pollen applied per larva. 95% confidence limit ranged between 19.38 and 48.8 pollen grains. So susceptibility of 2nd instar larvae of the European corn borer to B.t.-176 maize pollen is comparable to susceptibility of larvae of some other European or North American butterfly species which are common in agricultural used habitats. It is not possible to establish a laboratory rearing for most non-target-butterflies, which might possibly be affected by cultivation of B.t. plants. Therefore we suggest that the European corn borer, which is easy to rear under laboratory conditions, can be used as a test organism in a GMO environmental risk assessment to investigate potential side effects of pollen from newly developed B.t. plants, expressing the Cry1Ab deltaendotoxin, on larvae of non-target-lepidopterans from different groups (without Noctuidae).
URL:
Author: Gomez-B M, Berbel J, Rodriguez-Cerezo E
Year: 2008
Title: * Bt corn in Spain—the performance of the EU's first GM crop
Journal: Nature Biotechnology Contents: 26: 384-386 / Mon810 and others
Review / Currently, the only genetically-modified (GM) crop authorized for commercial cultivation in the European Union is a GM-maize resistant to maize borer by virtue of the transgenic expression of a gene encoding Bacillus thuringiensis (Bt) toxin. Spain now has over 9 years of experience in commercial cultivation of this type of GM maize (and is the European member state with the highest adoption rate for this GM variety), which makes it an opportune time to analyse ex post the agronomic and economic performance of Bt maize in Spain. This paper presents the results of this analysis, which is considered as the first for a GM crop cultivated in the EU.

Author: Gomez-Barbero M, Emilio Rodríguez-Cerezo
Year: 2008
Title: £ Adoption and socioeconomic impacts of the first genetically modified crop introduced in EU. agriculture: Bt maize in Spain (European Commission-DG JRC).
Journal: EUR : 22778 EN : Publication date: 6/2008
EU-DG-JRC - EUROPEAN COMMISSION -
DG JRC- Institute for Prospective Technological Studies
Sustainability in Agriculture, Food and Health Unit / Mon810 and others maizeBt
Review
Survey / This report analyses the process of adoption by farmers of the only GM crop cultivated in Europe. Bt maize is a transgenic crop resistant to an important group of pests (the maize borers). The report used data from a survey carried out among 402 commercial maize farms, including both adopters and non adopters of Bt maize during three growing seasons (2002-2004). Farmers were based in three Spanish provinces (Zaragoza, Lleida and Albacete) situated in leading Bt maize growing areas of Spain. All farmers were producing maize for feed manufacturing.
The survey found that Bt maize, like other pest-control technologies, produced variable impacts on maize yields in different provinces, ranging from neutral to 11.8% yield increase. Yield gains for growers of Bt maize were translated into revenue increase since no differences were found in the price paid to farmers for Bt or conventional maize. Regarding production costs, Bt maize growers paid more for the seeds than conventional growers, but had reduced insecticide use and costs. On average, growers of conventional maize applied 0.86 insecticide treatments/year to control borers versus 0.32 treatments/year applied by Bt maize growers. All things considered, the impact of Bt maize adoption on gross margin obtained by farmers in different provinces ranged from neutral to € 122/ha and year. In the survey, the reason most quoted by farmers for adopting Bt maize was "lowering the risk of maize borer damage" followed by "obtaining higher yields".
The report concludes that the differences in yields and gross margin are attributable to the adoption of Bt maize varieties and not to differences in the socio-economic profiles or technical capability of the farmers surveyed.
ftp://ftp.jrc.es/pub/EURdoc/JRC37046.pdf
Author: Guehlstorf NP
Year: 2008
Title: * Understanding the scope of farmer perceptions of risk: considering farmer opinions on the use of genetically modified (GM) crops as a stakeholder voice in policy.
Journal: Journal of Agricultural & Environmental Ethics 21 (6) 541-558 / GM general
Survey / This study explores the relationship of farmer attitudes and GM agriculture. A survey was conducted on 200 farmer adopters and non-adopters of GM crops within the counties of Madison, Macoupin, Jersey and Feyette in Illinois, USA on the perception of risk in relation to GM food production and current agricultural policies within the USA. Although national research indicates that larger yields are the most common reason for GM adoption, qualitative information suggest that the potential of GM crops to increase revenue per acre does not truly reflect all the concerns of modern farmers. For example, farmers who use GM seeds indicate that they constantly question the social impacts of their agricultural practices. As such, GM policies should be restructured as a political rationalization of both economic modelling and political theory because this research suggests that farmers' business decisions are utility calculations that consider economics without ignoring environmental and political contexts. Farmers' concerns about non-economic risks suggest that they need more information about GM crops and that governmental policies should respond to their interests, as they are more democratic or pluralistic than industry or consumer arguments.

Author: Hellmich Richard L, Ramon Albajes, David Bergvinson, Jarrad R. Prasifka, Zhen-Ying Wang and Michael J. Weiss