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Field trials were conducted in Japan under different growing conditions to better understand seed production of wild soybean (Glycine soja Seib. et Zucc.). The objectives of these trials were to evaluate yield and yield components of wild soybean: (1) across 11 diverse populations grown under favorable conditions to assess seed production potential, (2) under different planting densities (112, 208, 416, and 832 plants/m2) to assess intra-specific competition, and (3) across growing conditions (favorable, ruderal, and natural) to assess the impacts of environmental stress and inter-specific competition. Significant differences in yield and seed number observed among the evaluated wild soybean populations were predominantly due to environmental effects and genetic by environmental interaction. Seed production was impacted by both intra- and inter-specific competition. Wild soybean grown without plant competition had 51-fold and 247-fold higher yield compared to when grown in ruderal and natural environments, respectively. Under favorable growing conditions, wild soybean had substantial yield potential due to the ability to produce a high number of seeds. In nature, yield potential is severely limited because of plant competition and other environmental stressors. The results of this research are useful to inform environmental risk assessment when considering the potential impact of soybean biotechnology traits that increase or protect yield. If such traits were to be inadvertently transferred from imported soybean into wild soybean, this research indicates that the effects would likely have little overall impact on wild soybean seed production. [ABSTRACT FROM AUTHOR]

In commercializing a genetically engineered (GE) crop, agronomic characterization studies that contribute to environmental risk assessment (ERA) may be repeated in different global regions. Likewise, these studies may be done both for single‐event GE products and for traditional breeding crosses that combine GE events (breeding stacks). The objectives of this research were to assess the need for de novo agronomic characterization if previously done in another region or for each event in a breeding stack. Data were obtained for the GE maize (Zea mays L.) products MON 89034 (insect protected), NK603 (herbicide tolerant), and the breeding stack MON 89034 × NK603. The field trials were done from 2004 to 2014 in Argentina, Brazil, Mexico, Pakistan, and/or the United States. Sources of environmental diversity among the regions (i.e., countries) included differences in the prevalent climate classes of their sites. Although values for the agronomic characteristics varied among regions, event × region interactions caused <1% of the total variability for each GE product. Within each region, comparisons of GE products and near‐isogenic conventional controls were largely nonsignificant. When considering agronomic characteristics, a consistent risk assessment outcome—no evidence of increased potential to become a plant pest—was found in each region and for the single‐event products and the breeding stack. The results support ERA policies that provide for (i) acceptance of agronomic characterization data from other regions (data transportability) and (ii) exemption of breeding stacks from agronomic characterization, based on case‐by‐case assessments of plausible risks. [ABSTRACT FROM AUTHOR]

Insect-protected soybean (Glycine max (L.) Merr.) was developed to protect against foliage feeding by certain Lepidopteran insects. The assessment of potential consequences of transgene introgression from soybean to wild soybean (Glycine soja Seib. et Zucc.) is required as one aspect of the environmental risk assessment (ERA) in Japan. A potential hazard of insect-protected soybean may be hypothesized as transfer of a trait by gene flow to wild soybean and subsequent reduction in foliage feeding by Lepidopteran insects that result in increased weediness of wild soybean in Japan. To assess this potential hazard two studies were conducted. A three-year survey of wild soybean populations in Japan was conducted to establish basic information on foliage damage caused by different herbivores. When assessed across all populations and years within each prefecture, the total foliage from different herbivores was ≤ 30%, with the lowest levels of defoliation (< 2%) caused by Lepidopteran insects. A separate experiment using five levels of simulated defoliation (0%, 10%, 25%, 50% and 100%) was conducted to assess the impact on pod and seed production and time to maturity of wild soybean. The results indicated that there was no decrease in wild soybean plants pod or seed number or time to maturity at defoliation rates up to 50%. The results from these experiments indicate that wild soybean is not limited by lepidopteran feeding and has an ability to compensate for defoliation levels observed in nature. Therefore, the potential hazard to wild soybean from the importation of insect-protected soybean for food and feed into Japan is negligible. [ABSTRACT FROM AUTHOR]

Mexico, the center of origin of maize (Zea mays L.), has taken actions to preserve the identity and diversity of maize landraces and wild relatives. Historically, spatial isolation has been used in seed production to maintain seed purity. Spatial isolation can also be a key component for a strategy to minimize pollen-mediated gene flow in Mexico between transgenic maize and sexually compatible plants of maize conventional hybrids, landraces, and wild relatives. The objective of this research was to generate field maize-to-maize outcrossing data to help guide coexistence discussions in Mexico. In this study, outcrossing rates were determined and modeled from eight locations in six northern states, which represent the most economically important areas for the cultivation of hybrid maize in Mexico. At each site, pollen source plots were planted with a yellow-kernel maize hybrid and surrounded by plots with a white-kernel conventional maize hybrid (pollen recipient) of the same maturity. Outcrossing rates were then quantified by assessing the number of yellow kernels harvested from white-kernel hybrid plots. The highest outcrossing values were observed near the pollen source (12.9% at 1 m distance). The outcrossing levels declined sharply to 4.6, 2.7, 1.4, 1.0, 0.9, 0.5, and 0.5% as the distance from the pollen source increased to 2, 4, 8, 12, 16, 20, and 25 m, respectively. At distances beyond 20 m outcrossing values at all locations were below 1%. These trends are consistent with studies conducted in other world regions. The results suggest that coexistence measures that have been implemented in other geographies, such as spatial isolation, would be successful in Mexico to minimize transgenic maize pollen flow to conventional maize hybrids, landraces and wild relatives. [ABSTRACT FROM AUTHOR]

Environmental risk assessment is required for genetically modified (GM) crops before their import into Japan. Annual roadside monitoring along transportation routes from ports to processing facilities for GM soybean (Glycine max (L.) Merr.) have been requested as a condition of import only approval because of lack of information on the likelihood of persistence of imported GM soybean for food, feed and processing and the potential for transfer of transgenes into wild soybean (Glycine soja Seib. et Zucc.) through gene flow under the Japanese environment. The survey of soybean seeds, plants and wild soybean populations were conducted along transportation routes from unloading ports to processing facilities that provided data to help quantify actual exposure. The survey indicated that the opportunities for co-existence and subsequent crossing between wild soybean populations and imported soybean are highly unlikely. Together the survey results and the comprehensive literature review demonstrated low exposure of imported GM soybean used for food, feed and processing in Japan. This evaluation of exposure level is not specific to particular GM soybean event but can apply to any GM soybean traits used for food, feed and processing if their weediness or invasiveness are the same as those of the conventional soybean. [ABSTRACT FROM AUTHOR]

Environmental risk assessment is required for genetically modified (GM) crops before their import into Japan. Annual roadside monitoring along transportation routes from ports to processing facilities for GM soybean ( Glycine max (L.) Merr.) have been requested as a condition of import only approval because of lack of information on the likelihood of persistence of imported GM soybean for food, feed and processing and the potential for transfer of transgenes into wild soybean ( Glycine soja Seib. et Zucc.) through gene flow under the Japanese environment. The survey of soybean seeds, plants and wild soybean populations were conducted along transportation routes from unloading ports to processing facilities that provided data to help quantify actual exposure. The survey indicated that the opportunities for co-existence and subsequent crossing between wild soybean populations and imported soybean are highly unlikely. Together the survey results and the comprehensive literature review demonstrated low exposure of imported GM soybean used for food, feed and processing in Japan. This evaluation of exposure level is not specific to particular GM soybean event but can apply to any GM soybean traits used for food, feed and processing if their weediness or invasiveness are the same as those of the conventional soybean.