Monitoring GM crops: Sharing Country Experiences

Presentation 1. Monitoring GM crops in Canada. R. Blackshaw

Presentation 2. Monitoring GM crops in China. Bao-Rong Lu

Presentation 3. Monitoring GM Crops in Brazil. E. Fontes

Presentation 4. Field experience in monitoring GM crops in South Africa. G. Bothma

Robert Blackshaw outlined approaches to studying the environmental effects of GM crops in Canada, where 5 million hectares of GM crops are grown annually. A 12-year field experiment is examining environmental and economic effects of herbicide-tolerant (HT) canola, maize and potato (until 2003), and Bacillus thuringenesis (Bt) maize. Data include soil quality and weed seed bank at initiation, weed density by species (species shifts), assessments of resistance development, target insects and plant diseases, arthropod community dynamics (diversity), soil microbial biomass and diversity, transgenic DNA persistence in soil, Bt toxicity persistence in soil, DNA transfer to soil microorganisms, crop yield and quality, and production economics. A second study addresses an HT canola seed in the soil seed bank. It was pointed out that although much scientific evaluation is conducted before GM crops are approved for commercial production, post-commercialization studies are prudent because some environmental impacts of GM crops are likely to be scale- and/or time-dependent.

Bao-Rong Lu outlined methodologies for monitoring environmental effects of GM crops in China, with special emphasis on rice. Biosafety research has been funded on GM cotton, rice, soybean, wheat, tomato and Brassica species, including gene flow and its ecological consequences, impact of transgenes on non-target organisms, changes in biodiversity, development of Bt resistance, fitness of inter-specific hybrids, and field performance of GM crops. Research on rice and its wild relatives provides a model for selfing, wind-pollinated crops. It addresses pollen flow, crop-to-crop and crop-to-wild gene flow, biodiversity influences of GM rice, fitness performance of hybrids between GM rice and wild rice species, and cost-benefit analysis. The objectives are to determine the most effective methodologies for monitoring environmental effects of GM crops and to develop guidelines for safe management

Eliana Fontes presented details of monitoring for the environmental effects of GM crops in Brazil, where agricultural crops are grown in all five geographical regions, which differ in topography, climate, ecological and socio-economic characteristics and biodiversity. New agricultural technologies must fit within a culturally diverse society, a mega-biodiverse country and subsistence to industrial farming systems. Field trials of GM crops have been held since 1997, but only GMHT soybean is commercially cultivated. There are concerns about adverse effects on non-target organisms, and some crops have sexually compatible wild, feral and backyard relatives. Gene flow may pose a threat to the long-term preservation of crop species’ genetic diversity. The diversity of agricultural systems in Brazil and the variety of expertise and baseline information needed for monitoring, poses a significant challenge. A Post-Commercial Monitoring Plan required by the National Technical Biosafety Commission for commercial release of GMHT soybean and an impact assessment of Bt cotton were presented.

Gurling Bothma discussed field experience and methodologies for monitoring the environmental effects of GM crops in South Africa, where GM yellow and white maize, soybean and cotton are grown. Monitoring by seed suppliers is required by the Office of the Registrar: Genetically Modified Organisms Act, 1997⁵ to ensure refugia are maintained. Seed companies have established a GM Seed Standing Committee to coordinate an Insect Resistance Management system and a protocol is under development. Indirect monitoring of seed sales is also used to monitor the maintenance of refugia in cotton, to prevent resistance build up. A different strategy is used to manage and monitor compliance by less technologically advanced farmers. Companies selling the GMHT crops are required to monitor for herbicide resistance in weeds, but this has not been detected yet. Monitoring and management systems are being synchronized in South Africa to make them accessible across the diverse farming community.

Discussion Summary

• The types of variables to be monitored must be identified with the procedures to measure them and appropriate time-periods for measurement. Monitoring designs must be within logistic limits.


• All biodiversity effects in the UK FSEs arose from the effects of herbicides whose use was enabled by the GM technology rather than because of the mode of crop breeding.


• Although the FSEs were not monitoring studies, their design criteria (i.e., procedures built from a clear hazard scenario with an identified mechanism) were equivalent to those required in monitoring programme design.


• Several countries already have good procedures in place that provide a useful model for implementation in other countries, and some countries have made a commitment to conduct long-term research on monitoring environmental effects of GM crops.


• Several countries that have adopted GM crops do not have a monitoring process in place yet. In rice, to date, the major concern has been the presence of wild rice relatives and the impacts of the foreign gene in these species. The level of out-crossing between transgenic cultivated rice and weedy rice is still low; however, it may change as the infestation increases. Procedures are also needed to monitor the impact of GM soybean and cotton, but in several cases, countries did not have trained personnel or resources allocated to this purpose.


• In one example, the private sector has shown interest in investing in the monitoring process, but there is not enough human capacity to carry it out.


• Policy makers vary in their capacity to exploit details about GM crop ecological effects, and ecological impact data vary in the degree to which they can inform and assist the development of effective policy. Emphasis in some policy arenas tends to be on crop production goals, whereas in others (e.g., the EU), ecological effects are a priority.


• Monitoring must consider factors of concern to stakeholders, and to be effective, they must establish a relevant location, scale and duration. The specific GM traits may guide design, as may significant changes in crop management.


• Capacity building for GM crop monitoring is needed in developing countries. There should be a responsible institution/organization in the country to coordinate monitoring. CGIAR centres may help with regional implementation and play a role in information gathering.

⁵Office of the Registrar: Genetically Modified Organisms Act, 1997. http://www.info.gov.za/acts/1997/act15.htm