quinta-feira, 15 de setembro de 2011

Lá, como cá, a oposição ideológica atravessa a ciência

A Convenção de Biodiversidade tem nos grupos de experts ad-hoc um braço executivo de sua política geral de proteção ao meio ambiente. Os grupos são criados em resposta a demandas dos países membros quanto a questões específicas. Há vários anos alguns AHTEGs, como são chamados estes grupos, têm-se debruçado sobre várias questões candentes referentes ao meio ambiente. Alguns destes grupos atuam no contexto do Protocolo de Cartagena e se dedicam a várias questões ligadas aos organismos geneticamente modificados. Um grupo destes dedicou-se a produzir recomendações (guidelines) sobre avaliação/análise de risco e outros procuraram exemplificar a aplicação destas guidelines para plantas piramidades, plantas resistentes a estresse e mosquitos transgênicos.
Na opinião da maioria dos participantes dos fóruns on-line que avaliaram estes documentos previamente à MOP/COP, o objetivo não havia sido alcançado em nenhum dos 4 textos. De fato, os guidelines para avaliação de riscos não foram aceitos na MOP e tiveram que voltar a ser discutidos e aprimorados. Insensatamente, contudo, foi pedido que outros grupos se debruçassem sobre novas questões quando as anteriores ainda estavam largamente não resolvidas.
Dois outros assuntos foram priorizados: monitoramento pós-liberação comercial e avaliação de risco de árvores perenes (espécies florestais). Como esperado, o resultado foi um completo desastre. Para se ter uma idéia da inconsistência do trabalho, fruto da colocação de viés ideológico claramente anti-GM à frente da ciência, repassamos os comentários do Prof. Dr. Steve Strauss, da Oregon State University, EUA. Eles espelham os muitos outros comentários no fórum on-line e dezenas de outros fora dele, que repudiam o texto como um todo.
O fórum pode ser acessado pelo link abaixo. Da página do fórum pode-se baixar vários documentos, inclusive a proposta de avaliação de risco de florestas GM.


I am writing as an observer to comment on the document “RISK ASSESSMENT OF LIVING MODIFIED TREES” that was open for comment under the discussion group "Risk Assessment of LM Trees", 5-17 September 2011.

I am a Distinguished Professor of Forest Biotechnology in the College of Forestry at Oregon State University in the USA.  I have taught and conducted research in forest genetics and transgenic biotechnology for 30 years thus believe I understand both genetic, ecological, and surrounding social issues of GM trees in considerable depth.  You can view my background, publications and CV at this web site:http://www.cof.orst.edu/coops/tbgrc/Staff/strauss/index.htm 

I was most unhappy with the tenor and content of the document, and believe an entire rewrite is warranted.  It had many value judgments that posing as scientific statements of fact, and lacked sufficient context to guide the formulation and design of relevant risk assessments.

1. The document considered intensively grown tree plantations as equivalent to natural forests, when societies throughout the world have chosen to allow, and often to encourage, plantations because of their very high social and economic value for wood production compared to management and harvest of wild forests.  This is similar to the decision to create agricultural fields rather than to conduct a hunter-gatherer-foraging kind of food production.  These forests are intentionally highly simplified in ecological structure and diversity because of the large social benefits, and sparing on impacts on wild forests, that they bring.  The impacts from GM trees in plantation systems should only be compared to the already very large impacts implicit to plantation forests, such as from short planting and harvest cycles with evenly spaced plantations of single species or genotypes, usually under intensive weed control and fertilization.  Thus, consideration of “landscape architecture” and “ecosystem function services” (e.g. illness 222-223) needs to be considered within a social framework that has already chosen to simplify and allocate these amenities these in a highly differential manner. 

2. The document stated in more than one place that forest trees are “unique” (e.g., line 88 and nearby) or are “ecosystems in themselves” (e.g., line 100) or have “extensive interactions with other organisms” (e.g., line 145 and nearby) or are crucial to “food webs” (e.g., line 258).  In fact many of their traits including perennial habit, vegetative persistence, and support of complex ecological communities are shared by many other plant species that are not trees nor part of forests.  The long-lived grasses that dominate native prairies are good examples.  Thus, these exaggerations and value judgments do not belong in a scientific document.
3. Wood was considered as a potential vegetative propagule with respect to possible transboundary movement, and thus movement of wood should be carefully considered (line 131 and nearby).  The large majority of wood is dead and unable to serve as propagules; only rarely, when dormant and well-preserved branch or root sections are shipped, are they effective propagues, and even then usually need to be planted and cared for by humans.  Likewise, normal vegetative propagule movement, such as through branches, is rarely found outside of the Salicaeae among industrially grown plantation trees.  Moreover, even there it is the major source of spread only special environments, such as in high elevation and wild Populus tremula/tremuloides (where no GM trees are intended). Thus, the sections are misleading.

4. The document often said that forest trees were little domesticated (e.g., see line 106 and 205 and nearby).  In fact, some of the most widely grown and intensively bred trees are highly domesticated, which can be accomplished in a single generation in case the case of interspecific hybrids in Populus and Eucalyptus.  These trees are usually highly infertile because of their hybrid genotypes and often produce highly variable and maladapted progeny, thus are substantially domesticated with respect to their ability to invade natural habitats.  These are the same types of genotypes most likely to use GM varieties in plantation forestry in the future. 

5. The conventional wisdom of tree breeding that local rather than exotic provenances are best (lines 147-153) are now being seriously questioned worldwide as global climate change substantially alters growing seasons, frost periods, high temperatures, and drought cycles.  Exotic kinds of trees, including some kinds of GM trees with enhanced abiotic or biotic stress tolerance properties, may be desirable and important for sustaining forest productivity and even survival in many environments. 

6. The document focuses on risks of changes to status quo, however, the rapidly rising world demand for solid wood, pulp, and bioenergy products—together with increased climate and forest pest injury—is putting serious and growing stresses on all kinds of forests.  The document lacks any perspectives on the risks to forests of doing nothing with advanced GM methods given these serious social and ecological stresses.  The long term and ecologically thorough risk assessments demanded throughout the document will make the use of GM increasingly impractical, taking a major tool for plantation forest improvement away from tree breeders (in fact, this has already begun under the CBD:  Strauss, S.H., H. Tan, W. Boerjan, and R. Sedjo. (2009) Strangled at birth? Forest biotech and the Convention on Biological Diversity. Nature Biotechnology 27:519-527).  .  Tree breeders themselves rarely wait for more than a fraction of a rotation to begin to make selection decisions, thus there is no reason for the more specifically modified GM trees to do otherwise.
7. The document suggests that instability of transgenic traits in trees is a serious issue (line 88 and nearby).  However, it is has been known for several years that stable expression of transgenes and associated traits is what is predominantly observed in the field with transgenic forest trees; instability is rare and easily managed (Brunner, A., J. Li, S. DiFazio, O. Shevchenko, R. Mohamed, B. Montgomery, A. Elias, K. Van Wormer, S.P. DiFazio, & S.H. Strauss. (2007) Genetic containment of forest plantations. Tree Genetics & Genomes 3:75-100).  Thus, the document is once again quite misleading.

I hope that these comments are useful.  As you can see, the flaws in perspective and fact are inherent to the very structure of the document—with its powerful anti-GM and anti-plantation bias.  I strongly urge that it be discarded and a new, more neutral document be drafted.

Thanks for considering these comments
Steve Strauss, Distinguished Professor

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