Garrett et al’s recent letter (2013 Environ. Res. Lett. 8 044055) shows the trade value of Brazil’s production of non-genetically modified (GM) crops, and argues that production for this niche market laid the foundation for the expansion of a variety of non-GM and eco-certification systems. We argue that the conditions underlying the development and perpetuation of the non-GM certification systems are transient. The expansion of soy production has dampened the conditions that promoted the dominance of non-GM soy in the region. The state at the heart of the production of conventional soy, Mato Grosso, already has transitioned to almost 90% GM soy in the most recent agricultural season. The continued viability of eco-certification systems depends on strengthening institutions on the demand side, and ensuring farm-level costs on the supply side match price premiums reaching the farm level.

中文翻译：

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巴西大豆和玉米供应链的生态认证和绿化

Garrett 等人最近的一封信 (2013 Environ. Res. Lett. 8 044055) 显示了巴西生产非转基因 (GM) 作物的贸易价值，并认为针对这一利基市场的生产为扩大品种奠定了基础非转基因和生态认证系统。我们认为，非转基因认证体系发展和延续的基础条件是暂时的。大豆产量的扩大抑制了促进非转基因大豆在该地区占据主导地位的条件。位于传统大豆生产中心的马托格罗索州在最近的农业季节已经过渡到近 90% 的转基因大豆。生态认证系统的持续生存能力取决于加强需求方的机构，