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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]

Biological and ecological data collected on a genetically modified crop and an appropriate control are useful for assessing potential ecological risk. Specific characteristics studied are selected on the basis of relevance to potential ecological effects, are well known, and are accepted by plant breeders. In these studies, germination, vegetative and reproductive growth, or ecological characteristics of Roundup Ready Flex cotton, MON 88913 were compared with a negative control, MON 88913(-). Statistically significant differences, when detected, were considered in the context of the genetic variation known to occur in cotton and their potential impact on plant pest (weed) potential (ecological risk). Experimental results revealed no effects of the genetic modification that would result in increased pest potential or ecological risk of MON 88913 compared with MON 88913(-).

Abstract: Herbicides classified as synthetic auxins have been most commonly used to control broadleaf weeds in a variety of crops and in non‐cropland areas since the first synthetic auxin herbicide (SAH), 2,4‐D, was introduced to the market in the mid‐1940s. The incidence of weed species resistant to SAHs is relatively low considering their long‐term global application with 30 broadleaf, 5 grass, and 1 grass‐like weed species confirmed resistant to date. An understanding of the context and mechanisms of SAH resistance evolution can inform management practices to sustain the longevity and utility of this important class of herbicides. A symposium was convened during the 2nd Global Herbicide Resistance Challenge (May 2017; Denver, CO, USA) to provide an overview of the current state of knowledge of SAH resistance mechanisms including case studies of weed species resistant to SAHs and perspectives on mitigating resistance development in SAH‐tolerant crops. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [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]

As part of an ecological risk assessment, Roundup Ready 2 Yield® soybean (MON 89788) was compared to a conventional control soybean variety, A3244, for disease and arthropod damage, plant response to abiotic stress and cold, effects on succeeding plant growth (allelopathic effects), plant response to a bacterial symbiont, and effects on the ability of seed to survive and volunteer in a subsequent growing season. Statistically significant differences between MON 89788 and A3244 were considered in the context of the genetic variation known to occur in soybean and were assessed for their potential impact on plant pest (weed) potential and adverse environmental impact. The results of these studies revealed no effects of the genetic modification that would result in increased pest potential or adverse environmental impact of MON 89788 compared with A3244. This paper illustrates how such characterization studies conducted in a range of environments where the crop is grown are used in an ecological risk assessment of the genetically modified (GM) crop. Furthermore, risk assessors and decision makers use this information when deciding whether to approve a GM crop for cultivation in—or grain import into—their country. [ABSTRACT FROM AUTHOR]

Laboratory studies were conducted to identify the sex pheromone of Tyta luctuosa (Denis and Schiffermuller), a Eurasian noctuid moth that has been imported and released to aid in control of field bindweed, Convolvulus arvensis L. Using gas chromatography-mass spectrometry, together with electroantennogram and windtunnel bioassays of male moths, two compounds, (Z)9-tetradecenal and (Z)-11-hexadecenal, were identified as the major pheromone components. Wholegland extracts contained these components, as well as two other major compounds, (Z)-9-tetradecanol and (Z)-11-hexadecanol. However, the two alcohols were not detected in airborne emissions of calling females. Ratios of Z9-14:ALD to Z11-16:ALD were markedly different for whole-gland extracts and airborne emissions (1:3 and 2:1, respectively). Also, although the total amount of the two compounds varied nearly eight-fold among individuals (22-167 ng, mean 75 ± 56 ng [SD]) in gland extracts, the Z9-14:ALD/Z11-16:ALD ratio was relatively constant (0.3 ± 0.15). On average, calling females released 94 ng of Z9-14:ALD and 45 ng Z11-16:ALD per hour, with a mean ratio of 2.2. In wind tunnel tests, 69% of males exhibited complete upwind flights and touched the stimulus source in response to a synthetic pheromone blend that mimicked the female-produced Z9-14:ALD/Z11-16:ALD airborne concentration and ratio, as compared with 82% and 50% in response to calling females and pheromone gland extracts, respectively. Tyta luctuosa adults are vagile, and both adults and larvae are cryptie in the field-factors that make recoveries of released insects unlikely. Therefore, our data will contribute to the development of a pheromone-based monitoring tool to help assess colonization and establishment of this potentially useful weed biological control agent. [ABSTRACT FROM AUTHOR]

The front cover image of the herbicide, 2,4‐D, inside the deep binding pocket of the auxin receptor protein known as TIR1, by Roberto Busi et al., is based on the Review Weed resistance to synthetic auxin herbicides, DOI: 10.1002/ps.4823. [ABSTRACT FROM AUTHOR]