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Background and Aims Condensed tannins, responsible for berry and wine astringency, may have been selected during grapevine domestication. This work examines the phylogenetic distribution of condensed tannins throughout the Vitaceae phylogenetic tree. Methods Green berries and mature leaves of representative true-to-type members of the Vitaceae were collected before ‘véraison’, freeze-dried and pulverized, and condensed tannins were measured following depolymerization by nucleophilic addition of 2-mercaptoethanol to the C4 of the flavan-3-ol units in an organic acidic medium. Reaction products were separated and quantified by ultrahigh pressure liquid chromatography/diode array detection/mass spectrometry. Key Results and Conclusions The original ability to incorporate epigallocatechin (EGC) into grapevine condensed tannins was lost independently in both the American and Eurasian/Asian branches of the Vitaceae, with exceptional cases of reversion to the ancestral EGC phenotype. This is particularly true in the genus Vitis, where we now find two radically distinct groups differing with respect to EGC content. While Vitis species from Asia are void of EGC, 50 % of the New World Vitis harbour EGC. Interestingly, the presence of EGC is tightly coupled with the degree of leaf margin serration. Noticeably, the rare Asian EGC-forming species are phylogenetically close to Vitis vinifera, the only remnant representative of Vitis in Eurasia. Both the wild ancestral V. vinifera subsp. sylvestris as well as the domesticated V. vinifera subsp. sativa can accumulate EGC and activate galloylation biosynthesis that compete for photoassimilates and reductive power.

Various reports recently informed about the effects of contaminated or adulterated wax foundations as a main cause of poor brood and colony development. Beekeepers reported that affected colonies were showing a holey brood pattern and a decline in population size. Twenty-five samples of wax foundations were collected from different sources in Germany. Samples were analyzed using a multi-residue analysis for 147 insecticides, acaricides, and varroacides to investigate the actual load of contamination in beeswax. Furthermore, the effect of selected contaminated and/or adulterated wax foundations on colony and brood development of honeybees was evaluated under field conditions. Our results show that 38 active substances in total were found in the wax samples. Acaricides used in-hive were the most frequently detected contaminants at high concentrations. Trace concentrations of plant protection products and biocides were also found. In the field trials, a significant influence of stearin-adulterated wax on population size, the number of capped brood cells, and termination rate was found compared with the reference. No detectable effects of other treatments on the investigated parameters were observed.

International audience; BACKGROUND Over the past decade, demethylation inhibitor (DMI) and succinate dehydrogenase inhibitor (SDHI) fungicides have been extensively used to control to septoria tritici blotch, caused by Zymoseptoria tritici on wheat. This has led to the development and selection of alterations in the target-site enzymes (CYP51 and SDH, respectively). RESULTS Taking advantage of newly and previously developed qPCR assays, the frequency of key alterations associated with DMI (CYP51-S524T) and SDHI (SDHC-T79N/I, C-N86S and C-H152R) resistance was assessed in Z. tritici-infected wheat leaf samples collected from commercial crops (n = 140) across 14 European countries prior to fungicide application in the spring of 2019. This revealed the presence of a West to East gradient in the frequencies of the most common key alterations conferring azole (S524T) and SDHI resistance (T79N and N86S), with the highest frequencies measured in Ireland and Great Britain. These observations were corroborated by sequencing (CYP51 and SDH subunits) and sensitivity phenotyping (prothioconazole-desthio and fluxapyroxad) of Z. tritici isolates collected from a selection of field samples. Additional sampling made at the end of the 2019 season confirmed the continued increase in frequency of the targeted alterations. Investigations on historical leaf DNA samples originating from different European countries revealed that the frequency of all key alterations (except C-T79I) has been gradually increasing over the past decade. CONCLUSION Whilst these alterations are quickly becoming dominant in Ireland and Great Britain, scope still exists to delay their selection throughout the wider European population, emphasizing the need for the implementation of fungicide antiresistance measures.

UMR BFP - Equipe Métabolisme; International audience; We analyzed a comprehensive set of contaminants in MON810 and NK603 genetically modified (GM) maize, and their non-GM counterparts, used in a rat feeding study (the GMO90 + project). Both the maize grains and the manufactured pellets were characterized. Only minor differences in contaminant levels between GM and corresponding non-GM harvests were evidenced. Fumonisin and deoxynivalenol mycotoxins were the pollutants present in the highest amounts, with concentrations that were however largely below acceptance reference values. Our data reporting slightly higher levels of fumonisin in MON810 compared to its non-GM counterpart corroborate the lower susceptibility of insect resistant Bt maize to fumonisin-producing fungi. Traces of glyphosate (0.016 mg/kg) were evidenced in grains from NK603 treated crops. Regarding the pellets, analysis of more than 650 potentially toxic substances revealed low amounts of various mycotoxins, pesticides and heavy metals. Concentrations of contaminants quantified in the pellets were however far below the maximum level of residues values set by regulatory agencies, and no substantial differences in contaminants between GM and non-GM pellets were observed. Moreover, when comparing the contamination status of grains and pellets, we demonstrate yet again that characterizing the grains is actually not sufficient to foresee the quality of the produced pellets.

International audience; Minor crops include mostly vegetables, fruits, nursery stock and ornamentals. These crops account for an EU production value of over (sic) 60 billion per year, representing more than 20% of the value of EU's total agricultural production. The sustainable production of such crops, from an economic point of view, is vital for both human health and European economies. For minor crops, this sustainability can only be realized by the continued availability of crop protection solutions for pest control. The number of minor crops in Europe without viable solutions for plant protection has increased in recent years. This is mainly due to the lack of pesticides in certain crops, as a number of previously authorized pesticides has not been re-authorized due to a stricter regulation. Also the introduction of tropical or sub-tropical crops and their pests into Europe has contributed to the problem of minor crops without any crop protection solutions as pesticides used elsewhere to protect these crops are not allowed in Europe. The limited range of pesticides available to farmers has increased the risk of resistance development since, in absence of a sufficient number of pesticides with various modes of action, farmers apply repetitively only a narrow spectrum of molecules. The direct economic impact due to the absence of viable plant protection solutions for minor crops has been estimated over a billion Euros per year, impacting 9 million hectares throughout Europe. In light of this, here we discuss the current state of the art of minor crops in Europe and elucidate ongoing efforts to address such problems through Integrated Pest Management (IPM). The information reported is expected to provide relevance of minor crops in Europe and encourage the development and implementation of effective IPM solutions.

The Rosaceae Conserved Orthologous Set (RosCOS) provides a gene-based genome-wide set of markers that have been used in comparative analyses of peach (Prunus persica), apple (Malus × domestica), and strawberry (Fragaria spp.). In order to extend the use of these RosCOS to sweet cherry (Prunus avium L.), we identified markers that are polymorphic in breeding germplasm. Ninety-five percent (595/627) of previously designed RosCOS primer pairs amplified a product in six sweet cherry cultivars predicted to represent the range of genetic diversity in breeding germplasm. A total of 45% (282/627) RosCOS were polymorphic among the six cultivars, and allele number ranged from 2 to 6, with a genome-wide mean of 2.35. A subset of 92 genome-wide single nucleotide polymorphisms (SNPs) corresponding to 76 RosCOS was analyzed in 36 founder accessions and progeny. The expected and observed heterozygosity suggested that 83% of the RosCOS were in Hardy–Weinberg equilibrium, implying that most RosCOS behave as neutral markers. Principal coordinate analysis (PCO) identified one wild accession and two Spanish landraces that clustered differently from the other accessions. The relatively high number of unique alleles found in the three differentially clustered selections suggested that their use as parents has potential to increase the genetic diversity in future US-bred cultivars. Of the 92 RosCOS SNPs, 81 SNPs that represented 68 genome-wide RosCOS segregated in four mapping populations. These RosCOS were mapped in four F1 populations, thereby greatly improving the genetic linkage map of sweet cherry.

International audience; Grapevines (Vitis vinifera L.) form the basis of viticulture, and are susceptible to diseases such as downy mildew (Plasmopara viticola) and powdery mildew (Erysiphe necator). Therefore, successful viticulture programs require the use of pesticides. Breeding for resistance is the only eco-friendly solution. Marker-assisted selection is currently widely used for grapevine breeding. Consequently, traits of interest must be tagged with molecular markers linked to quantitative trait loci (QTL). We herein present our findings regarding genetic mapping and QTL analysis of resistance to downy and powdery mildew diseases in the progenies of the GF.GA-47-42 ('Bacchus' x 'Seyval') x 'Villard blanc' cross. Simple sequence repeats and single nucleotide polymorphisms of 151 individuals were analyzed. A map consisting of 543 loci was screened for QTL analyses based on phenotypic variations observed in plants grown in the field or under controlled conditions. A major QTL for downy mildew resistance was detected on chromosome 18. For powdery mildew resistance, a QTL was identified on chromosome 15. This QTL was replaced by a novel QTL on chromosome 18 in 2003 (abnormally high temperatures) and 2004. Subsequently, both QTLs functioned together. Additionally, variations in the timing of the onset of veraison, which is a crucial step during grape ripening, were studied to identify genomic regions affecting this trait. A major QTL was detected on linkage group 16, which was supplemented by a minor QTL on linkage group 18. This study provides useful information regarding novel QTL-linked markers relevant for the breeding of disease-resistant grapevines adapted to current climatic conditions.

Times are changing for pest management in Europe. Stronger societal demands and pesticide resistance pressure farmers to reduce their reliance on pesticides more than ever before. Reconciling human health and environmental goals with production is a challenge for farmers as well as for all crop-protection stakeholders. Expectations that research and extension will quickly provide solutions are high everywhere. Although a few European countries have acquired experience with pesticide action plans or implementation of integrated pest management (IPM) guidelines on a national scale, many others are starting from a more modest base. Stakeholders in Europe are looking beyond their national borders to create synergies and share experiences and know-how. Representatives of the European Commission and Parliament, governments, research, extension, farmers, industry, and civil society are engaged in dynamic interactions. A Europe-wide structure (an ERA-Net) able to coordinate national calls for research and extension proposals on IPM is planned for 2014. Since 2007, the 10-country network ENDURE has pooled expertise among its 15 research, education, and extension member institutions. It has conducted joint reviews and original studies on IPM, organized summer schools, set up an internet-based platform on wheat cultivars and pathogens, and continues to support workshops, newsletters, and an information center with 1,600 entries for advisers. After earlier successes on insect pest management in North America or with resource-poor farmers in developing countries, Europe is set to become a source of renewed inspiration for IPM applied to conventional agriculture in industrialized countries and broadened to encompass all pest categories.

International audience