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The data set reported here includes the part of a Hot Serial Cereal Experiment (HSC) experiment recently used in the AgMIP-Wheat project to analyze the uncertainty of 30 wheat models and quantify their response to temperature. The HSC experiment was conducted in an open-field in a semiarid environment in the southwest USA. The data reported herewith include one hard red spring wheat cultivar (Yecora Rojo) sown approximately every six weeks from December to August for a two-year period for a total of 11 planting dates out of the 15 of the entire HSC experiment. The treatments were chosen to avoid any effect of frost on grain yields. On late fall, winter and early spring plantings temperature free-air controlled enhancement (T-FACE) apparatus utilizing infrared heaters with supplemental irrigation were used to increase air temperature by 1.3°C/2.7°C (day/night) with conditions equivalent to raising air temperature at constant relative humidity (i.e. as expected with global warming) during the whole crop growth cycle. Experimental data include local daily weather data, soil characteristics and initial conditions, detailed crop measurements taken at three growth stages during the growth cycle, and cultivar information. Simulations include both daily in-season and end-of-season results from 30 wheat models. Data access via doi 10.7910/DVN/M9ZT0F

International audience; It is a common agronomic practice to evaluate new varieties under natural field conditions. This applies to GM plants and for more than 25 years, numerous field trials were set up throughout the world to assess GM trees modified for an array of different traits. In this talk, I will stress some of the knowledge, we gained from these experiments. While recently a few GM tree events have been authorized for commercial release, in Europe, GM tree field trials remain limited in numbers, mainly because it is becoming increasingly difficult to obtain authorization for a GM tree field trial. This is in sharp contrast with all the experimental results issued from GM tree field trial experiments: 1) phenotypic effects resulting from transgene expression in GM trees grown in the field appear to be stable, albeit variable 2) most field studies have validated earlier observations made under greenhouse conditions, although in some cases the modification of target traits was less obvious in fluctuating field environments, and in a few cases, GM trees had severe growth and developmental penalties 3) non-target effects were consistently within the range of natural variation. Overall, the European GM tree field trials failed to identify any significant tangible risks. Based on this evidence, it seems appropriate that Europe should now move forward beyond small confined trials to larger scale experiments better fitted to a broader context of evaluation and environmental assessment.

For the last 20 years, as a complement to biochemical approaches, lignin-modified transgenic trees have proven to be invaluable tools for deciphering the lignin biosynthetic pathway and increasing our knowledge about the role of lignins in wood specific properties important for tree physiology. In addition, their evaluation in the field has been very useful for the identification of possible routes to improve wood properties for specific industrial uses, initially pulp and paper making and now biofuel production. In this chapter, we review our present knowledge gained through numerous studies analysing transgenic trees, with emphasis on field trial evaluations, for assessing the effects of lignin modification on wood properties and tree physiology. All the data presented here led to the conclusion that, prior to use in forestry for pulp and paper or bioenergy production, the fitness of lignin-modified transgenic trees required careful evaluation in a variety of field environments. Although limited in number, environmental studies failed to indicate any strong effects of lignin-modified transgenic trees on the ecosystem. Finally, this review helps to identify some promising options where biotech trees could be used to further optimize the production of wood for human uses.

Background Global warming, environmental disasters, and increasing oil prices have catalyzed a worldwide trend to use plant biomass as a renewable source for liquid biofuels and bio-based materials. Plant biomass can be processed into fermentable sugars by enzymatic depolymerization of the cell wall polysaccharides, followed by fermentation. However, the presence of lignin in the cell wall constitutes a major recalcitrance factor because it limits the accessibility of polysaccharidases to the cellulose microfibrils. To overcome this hurdle, plant biomass is pretreated in a costly and energyrequiring process. One approach to overcome the recalcitrance problem is to engineer lignin amount or alter its composition to make lignin more susceptible to chemical degradation [1]. Cinnamoyl-CoA reductase (CCR), the enzyme that converts feruloyl-CoA into coniferaldehyde, is considered the first enzyme in the monolignol-specific branch of the phenylpropanoid pathway. Poplar trees down-regulated in CCR have been produced in the early nineties and planted in a field trial in France to produce sufficient wood for small scale chemical pulping tests [2]. These trees had 20% lower lignin levels and relatively more cellulose per gram of wood [2]. Given that lignin is one of the main limiting factors limiting the conversion of plant biomass into fermentable sugars, and that poplar is considered as a promising second generation biofuel crop, we have re-grown these trees in the greenhouse and in the field, and evaluated wood produced from these trees by saccharification experiments. Methods Cinnamoyl-CoA reductase (CCR) expression was downregulated in poplar by sense and antisense strategies [2]. Transgenic trees were evaluated for lignin amount and composition [2] and for sugar release by saccharification assays [3]. After obtaining permission from the regulatory authorities, two transgenic lines were planted in a field trial in Belgium and two in a field trial in France, both under short rotation coppice culture to maximize biomass production. Wood was saccharified with and without acid pretreatment.

International audience; Chlordecone is an organochlorine pesticide whose use is now forbidden but which persists in soils. It was used as an insecticide against the banana weevil from the 1970s to the early 1990s in the French West Indies. Late contamination of root vegetables (RVs) was revealed in 2002. In our work, we studied the mode of transfer of chlordecone from different types of tropical soil (Andosol, Ferralsol and Nitisol) to different RVs (dasheen, yam, sweet potato, turnip and radish) to explore plant sensitivity to contamination. We conducted complementary experiments: surveys, field trials, and mesocosm trials to link soil chlordecone content with plant chlordecone contamination. In all those experiments, RVs contamination was heterogeneous as soil pollution was heterogeneous, but dispersion of the chlordecone molecule was the same for each crop. Due to this dispersion, the soil type did not significantly affect contamination. Average contamination values measured in harvested organs were positively correlated to chlordecone soil content. Belowground organs themselves were contaminated heterogeneously depending on where there was direct contact between the organ and contaminated soil. The cortex was more highly contaminated than the pulp (up to ten times more). These two results thus support the hypothesis that contamination by direct contact between the chlordecone molecule and the plant organ is the most important mode of transfer in RVs. This has already been demonstrated in the yam Discorea cayenensis, whose tubers were chlordecone free even when the root system explored contaminated soil. Chlordecone diffusion into the plant was very weak suggesting that it is a passive process in RVs. A common model, based on morphology and duration of the soil/organ contact, accounted for the RVs contamination. We calculated an envelope curve of the relationship between soil chlordecone content and RVs contamination and the maximum transfer ratio observed was 1/5. This envelope curve which represents zero risk of contamination was calculated for crops on both Andosol and Ferralsol. This relationship is thus a decision tool to determine whether or not there is a risk involved in cultivating roots and tubers based on the result of soil analysis. With this tool, the risk of contamination can be foreseen at planting which is preferable to analyzing the product at the harvest stage. Further studies are in progress to determine the sensitivity of other mainly horticultural crops and fruits, and to analyze the contamination of aboveground organs. Factors that govern the bioavailability of the chlordecone molecule in the soil for the plants, like water, organic matter content, type of clay, need to be analyzed in more detail to better understand chlordecone transfer to plants and thus improve pollution management

Culture of Bartlett on its own roots. Comparaisons with Quince and French seedling rootstocks