The three cool-season perennial forage grasses cocksfoot/orchardgrass, Dactylis glomerata L., tall fescue, Festuca arundinacea Schreb. syn. Lolium arundinaceum (Schreb.) Darbysh., and phalaris/harding grass, Phalaris aquatica L., are of major economic and ecological importance in regions with summer-dry environments. This review considers the constraints that these species are likely to experience under current and predicted increase of droughts due to climate change scenarios in south-eastern Australia, the southern Great Plains of USA and the Western Mediterranean Basin. The review identifies research required to maximise the development and use of C3 cool-season grasses with enhanced resilience to drought while considering the concern of some regulators that these grasses may be potential weeds. The state of knowledge of factors influencing plant drought survival and therefore recovery after stress and long-term persistence is discussed in the light of adaptive strategies. The major research needs identified to enhance traits conferring drought survival include (1) increasing the depth and density of grass root systems to strengthen dehydration avoidance; (2) exploring the biochemical, molecular and hydraulic bases of dehydration tolerance and improving techniques to measure this trait; (3) breaking the trade-off between summer dormancy and forage yield potential and improving understanding of environmental, biochemical and genetic controls over summer dormancy; (4) identifying non-toxic endophyte strains compatible with summer-dormant cultivars of tall fescue to enhance drought survival; and (5) enhancing seed production capability of new cultivars as well as the development of agronomic management packages for promoting stable mixtures combining perennial grasses and legumes. The weed potential of newly introduced summer-dormant cultivars is concluded to be minor. The research directions proposed here should improve pasture grass resilience and forage crop sustainability in Mediterranean and temperate summer-dry environments under the future drier and warmer conditions associated with climate change.

The three cool-season perennial forage grasses cocksfoot/orchardgrass, Dactylis glomerata L., tall fescue, Festuca arundinacea Schreb. syn. Lolium arundinaceum (Schreb.) Darbysh., and phalaris/harding grass, Phalaris aquatica L., are of major economic and ecological importance in regions with summer-dry environments. This review considers the constraints that these species are likely to experience under current and predicted increase of droughts due to climate change scenarios in south-eastern Australia, the southern Great Plains of USA and the Western Mediterranean Basin. The review identifies research required to maximise the development and use of C3 cool-season grasses with enhanced resilience to drought while considering the concern of some regulators that these grasses may be potential weeds. The state of knowledge of factors influencing plant drought survival and therefore recovery after stress and long-term persistence is discussed in the light of adaptive strategies. The major research needs identified to enhance traits conferring drought survival include (1) increasing the depth and density of grass root systems to strengthen dehydration avoidance; (2) exploring the biochemical, molecular and hydraulic bases of dehydration tolerance and improving techniques to measure this trait; (3) breaking the trade-off between summer dormancy and forage yield potential and improving understanding of environmental, biochemical and genetic controls over summer dormancy; (4) identifying non-toxic endophyte strains compatible with summer-dormant cultivars of tall fescue to enhance drought survival; and (5) enhancing seed production capability of new cultivars as well as the development of agronomic management packages for promoting stable mixtures combining perennial grasses and legumes. The weed potential of newly introduced summer-dormant cultivars is concluded to be minor. The research directions proposed here should improve pasture grass resilience and forage crop sustainability in Mediterranean and temperate summer-dry environments under the future drier and warmer conditions associated with climate change.

The three cool-season perennial forage grasses cocksfoot/orchardgrass, Dactylis glomerata L., tall fescue, Festuca arundinacea Schreb. syn. Lolium arundinaceum (Schreb.) Darbysh., and phalaris/harding grass, Phalaris aquatica L., are of major economic and ecological importance in regions with summer-dry environments. This review considers the constraints that these species are likely to experience under current and predicted increase of droughts due to climate change scenarios in south-eastern Australia, the southern Great Plains of USA and the Western Mediterranean Basin. The review identifies research required to maximise the development and use of C3 cool-season grasses with enhanced resilience to drought while considering the concern of some regulators that these grasses may be potential weeds. The state of knowledge of factors influencing plant drought survival and therefore recovery after stress and long-term persistence is discussed in the light of adaptive strategies. The major research needs identified to enhance traits conferring drought survival include (1) increasing the depth and density of grass root systems to strengthen dehydration avoidance; (2) exploring the biochemical, molecular and hydraulic bases of dehydration tolerance and improving techniques to measure this trait; (3) breaking the trade-off between summer dormancy and forage yield potential and improving understanding of environmental, biochemical and genetic controls over summer dormancy; (4) identifying non-toxic endophyte strains compatible with summer-dormant cultivars of tall fescue to enhance drought survival; and (5) enhancing seed production capability of new cultivars as well as the development of agronomic management packages for promoting stable mixtures combining perennial grasses and legumes. The weed potential of newly introduced summer-dormant cultivars is concluded to be minor. The research directions proposed here should improve pasture grass resilience and forage crop sustainability in Mediterranean and temperate summer-dry environments under the future drier and warmer conditions associated with climate change.

Plants are constantly exposed to a variety of biotic and abiotic stresses that reduce their fitness and performance. At the molecular level, the perception of extracellular stimuli and the subsequent activation of defense responses require a complex interplay of signaling cascades, in which protein phosphorylation plays a central role. Several studies have shown that some members of the Leucine-Rich Repeat Receptor-Like Kinase (LRR-RLK) family are involved in stress and developmental pathways. We report here a systematic analysis of the role of the members of this gene family by mutant phenotyping in the monocotyledon model plant rice, Oryza sativa. We have then targeted 176 of the ∼320 LRR-RLK genes (55.7%) and genotyped 288 mutant lines. Position of the insertion was confirmed in 128 lines corresponding to 100 LRR-RLK genes (31.6% of the entire family). All mutant lines harboring homozygous insertions have been screened for phenotypes under normal conditions and under various abiotic stresses. Mutant plants have been observed at several stages of growth, from seedlings in Petri dishes to flowering and grain filling under greenhouse conditions. Our results show that 37 of the LRR-RLK rice genes are potential targets for improvement especially in the generation of abiotic stress tolerant cereals.

Plants are constantly exposed to a variety of biotic and abiotic stresses that reduce their fitness and performance. At the molecular level, the perception of extracellular stimuli and the subsequent activation of defense responses require a complex interplay of signaling cascades, in which protein phosphorylation plays a central role. Several studies have shown that some members of the Leucine-Rich Repeat Receptor-Like Kinase (LRR-RLK) family are involved in stress and developmental pathways. We report here a systematic analysis of the role of the members of this gene family by mutant phenotyping in the monocotyledon model plant rice, Oryza sativa. We have then targeted 176 of the ?320 LRR-RLK genes (55.7%) and genotyped 288 mutant lines. Position of the insertion was confirmed in 128 lines corresponding to 100 LRR-RLK genes (31.6% of the entire family). All mutant lines harboring homozygous insertions have been screened for phenotypes under normal conditions and under various abiotic stresses. Mutant plants have been observed at several stages of growth, from seedlings in Petri dishes to flowering and grain filling under greenhouse conditions. Our results show that 37 of the LRR-RLK rice genes are potential targets for improvement especially in the generation of abiotic stress tolerant cereals. (Résumé d'auteur)

BGPI : équipe 4 | International audience | Plants are constantly exposed to a variety of biotic and abiotic stresses that reduce their fitness and performance. At the molecular level, the perception of extracellular stimuli and the subsequent activation of defense responses require a complex interplay of signaling cascades, in which protein phosphorylation plays a central role. Several studies have shown that some members of the Leucine-Rich Repeat Receptor-Like Kinase (LRR-RLK) family are involved in stress and developmental pathways. We report here a systematic analysis of the role of the members of this gene family by mutant phenotyping in the monocotyledon model plant rice, Oryza sativa. We have then targeted 176 of the ∼320 LRR-RLK genes (55.7%) and genotyped 288 mutant lines. Position of the insertion was confirmed in 128 lines corresponding to 100 LRR-RLK genes (31.6% of the entire family). All mutant lines harboring homozygous insertions have been screened for phenotypes under normal conditions and under various abiotic stresses. Mutant plants have been observed at several stages of growth, from seedlings in Petri dishes to flowering and grain filling under greenhouse conditions. Our results show that 37 of the LRR-RLK rice genes are potential targets for improvement especially in the generation of abiotic stress tolerant cereals.

Targeted sequence capture is a promising technology which helps reduce costs for sequencing and genotyping numerous genomic regions in large sets of individuals. Bait sequences are designed to capture specific alleles previously discovered in parents or reference populations. We studied a set of 135 RILs originating from a cross between an emmer cultivar (Dic2) and a recent durum elite cultivar (Silur). Six thousand sequence baits were designed to target Dic2 vs. Silur polymorphisms discovered in a previous RNAseq study. These baits were exposed to genomic DNA of the RIL population. Eighty percent of the targeted SNPs were recovered, 65% of which were of high quality and coverage. The final high density genetic map consisted of more than 3,000 markers, whose genetic and physical mapping were consistent with those obtained with large arrays.

Targeted sequence capture is a promising technology which helps reduce costs for sequencing and genotyping numerous genomic regions in large sets of individuals. Bait sequences are designed to capture specific alleles previously discovered in parents or reference populations. We studied a set of 135 RILs originating from a cross between an emmer cultivar (Dic2) and a recent durum elite cultivar (Silur). Six thousand sequence baits were designed to target Dic2 vs. Silur polymorphisms discovered in a previous RNAseq study. These baits were exposed to genomic DNA of the RIL population. Eighty percent of the targeted SNPs were recovered, 65% of which were of high quality and coverage. The final high density genetic map consisted of more than 3,000 markers, whose genetic and physical mapping were consistent with those obtained with large arrays.

Mycotoxins and trace elements are contaminants whose content in harvested organs is regulated forfeed and food. The tightening of European regulations requires to better understand the state anddeterminism of these contaminations. The proposed approach of multicontaminants raised descriptiveand explicative data contamination in field conditions and their cross effects. In order to have a range ofsoil and climatic situations, the work was based on a permanent national network of plots. The firsthypotheses of relationships between environmental factors, the technical process and contaminationswere proposed. To ensure reproducibility and traceability of samples and measurements, a samplingguide for wheat and sunflower grains has been defined and validated for the determination of traceelement concentrations in wheat grain and sunflower. | Les mycotoxines et les éléments traces sont des contaminants dont la teneur dans les organes récoltés est réglementée pour l’alimentation animale et humaine. Le durcissement des règlementations européennes entraîne la nécessité de mieux connaître l’état et le déterminisme de ces contaminations. L’approche multicontaminants proposée a permis de recueillir des données descriptives et explicatives des contaminations en conditions de plein champ et de leurs effets croisés. Afin de disposer d’une diversité de situations pédologiques et climatiques, les travaux se sont appuyés sur un réseau pérenne de parcelles mis en place à l’échelle du territoire national. Des premières hypothèses relatives aux relations entre les facteurs du milieu, l’itinéraire technique et l’apparition des contaminations ont été émises. Pour garantir la reproductibilité du prélèvement et la traçabilité des échantillons et mesures, un guide d’échantillonnage de grains de blé et de tournesol a été défini et validé pour la détermination de la concentration en éléments traces dans les grains de blé tendre et de tournesol.

Mycotoxins and trace elements are contaminants whose content in harvested organs is regulated forfeed and food. The tightening of European regulations requires to better understand the state anddeterminism of these contaminations. The proposed approach of multicontaminants raised descriptiveand explicative data contamination in field conditions and their cross effects. In order to have a range ofsoil and climatic situations, the work was based on a permanent national network of plots. The firsthypotheses of relationships between environmental factors, the technical process and contaminationswere proposed. To ensure reproducibility and traceability of samples and measurements, a samplingguide for wheat and sunflower grains has been defined and validated for the determination of traceelement concentrations in wheat grain and sunflower. | Les mycotoxines et les éléments traces sont des contaminants dont la teneur dans les organes récoltés est réglementée pour l’alimentation animale et humaine. Le durcissement des règlementations européennes entraîne la nécessité de mieux connaître l’état et le déterminisme de ces contaminations. L’approche multicontaminants proposée a permis de recueillir des données descriptives et explicatives des contaminations en conditions de plein champ et de leurs effets croisés. Afin de disposer d’une diversité de situations pédologiques et climatiques, les travaux se sont appuyés sur un réseau pérenne de parcelles mis en place à l’échelle du territoire national. Des premières hypothèses relatives aux relations entre les facteurs du milieu, l’itinéraire technique et l’apparition des contaminations ont été émises. Pour garantir la reproductibilité du prélèvement et la traçabilité des échantillons et mesures, un guide d’échantillonnage de grains de blé et de tournesol a été défini et validé pour la détermination de la concentration en éléments traces dans les grains de blé tendre et de tournesol.

Ce 49ème volume de la Revue Innovations Agronomiques regroupe l'ensemble de la restitution des projets Casdar, présentés le 3 novembre 2015. | Mycotoxins and trace elements are contaminants whose content in harvested organs is regulated for feed and food. The tightening of European regulations requires to better understand the state and determinism of these contaminations. The proposed approach of multicontaminants raised descriptive and explicative data contamination in field conditions and their cross effects. In order to have a range of soil and climatic situations, the work was based on a permanent national network of plots. The first hypotheses of relationships between environmental factors, the technical process and contaminations were proposed. To ensure reproducibility and traceability of samples and measurements, a sampling guide for wheat and sunflower grains has been defined and validated for the determination of trace element concentrations in wheat grain and sunflower. | Les mycotoxines et les éléments traces sont des contaminants dont la teneur dans les organes récoltés est réglementée pour l’alimentation animale et humaine. Le durcissement des règlementations européennes entraîne la nécessité de mieux connaître l’état et le déterminisme de ces contaminations. L’approche multicontaminants proposée a permis de recueillir des données descriptives et explicatives des contaminations en conditions de plein champ et de leurs effets croisés. Afin de disposer d’une diversité de situations pédologiques et climatiques, les travaux se sont appuyés sur un réseau pérenne de parcelles mis en place à l’échelle du territoire national. Des premières hypothèses relatives aux relations entre les facteurs du milieu, l’itinéraire technique et l’apparition des contaminations ont été émises. Pour garantir la reproductibilité du prélèvement et la traçabilité des échantillons et mesures, un guide d’échantillonnage de grains de blé et de tournesol a été défini et validé pour la détermination de la concentration en éléments traces dans les grains de blé tendre et de tournesol.

Psyllids are vectors of phytoplasma, which cause important diseases of pome fruit trees. Psyllid species reported as phytoplasma vectors were captured during 2010–2011 in several pome fruit growing regions in Turkey. Potential psyllid vectors of ‘Candidatus Phytoplasma mali’ were collected from Malus spp. (apple), Cydonia oblonga (quince), Crataegus spp. (hawthorn) and also from the overwintering hosts, whereas those of ‘Candidatus Phytoplasma pyri’ were collected from wild and cultured forms of Pyrus spp. (pear) trees. The psyllids were identified morphologically as Cacopsylla picta, C. melanoneura-C. affinis complex, C. crataegi, C. pyrisuga, C. pyri, C. pyricola and other Cacopsylla species. The highest natural phytoplasma infection rate was found in C. picta followed by C. pyri, C. melanoneura-C. affinis complex and C. crataegi with rates of 4.36, 3.84, 2.77 and 1.67%, respectively. No phytoplasma were detected in C. pyrisuga, C. pyricola, or the other Cacopsylla spp. ‘Ca. P. mali’ was detected in C. picta, C. melanoneura-C. affinis complex and C. pyri; ‘Ca. P. pyri’ was detected in C. picta, C. crataegi, C. melanoneura-C. affinis complex and C. pyri individuals. To our knowledge, this is the first report on the possible psyllid vectors of ‘Ca. P. mali’ in Turkey.

BGPI : équipe 6 | Psyllids are vectors of phytoplasma, which cause important diseases of pome fruit trees. Psyllid species reported as phytoplasma vectors were captured during 2010–2011 in several pome fruit growing regions in Turkey. Potential psyllid vectors of ‘Candidatus Phytoplasma mali’ were collected from Malus spp. (apple), Cydonia oblonga (quince), Crataegus spp. (hawthorn) and also from the overwintering hosts, whereas those of ‘Candidatus Phytoplasma pyri’ were collected from wild and cultured forms of Pyrus spp. (pear) trees. The psyllids were identified morphologically as Cacopsylla picta, C. melanoneura-C. affinis complex, C. crataegi, C. pyrisuga, C. pyri, C. pyricola and other Cacopsylla species. The highest natural phytoplasma infection rate was found in C. picta followed by C. pyri, C. melanoneura-C. affinis complex and C. crataegi with rates of 4.36, 3.84, 2.77 and 1.67%, respectively. No phytoplasma were detected in C. pyrisuga, C. pyricola, or the other Cacopsylla spp. ‘Ca. P. mali’ was detected in C. picta, C. melanoneura-C. affinis complex and C. pyri; ‘Ca. P. pyri’ was detected in C. picta, C. crataegi, C. melanoneura-C. affinis complex and C. pyri individuals. To our knowledge, this is the first report on the possible psyllid vectors of ‘Ca. P. mali’ in Turkey.

Le groupe des Pseudomonas syringae est très divers, au niveau phénotypique, génétique et de ses habitats. Récemment, 13 phylogroupes et 23 clades qui prennent en compte la diversité génétique et celle des habitats de cette bactérie ubiquiste ont été décrits (Berge et al., 2014). Des outils moléculaires permettant d’identifier les P. syringae et leur phylogroupes ont été développés au laboratoire (Borschinger et al., soumis), et nous permettent de travailler sur de relativement grands effectifs d’isolats bactériens. Avec ces outils, en réalisant nous-même des prélèvements dans des vergers ciblés en 2014 et 2015, et en collaboration avec le CTIFL qui a réalisé deux importantes prospections en 2011-2012, nous avons exploré la diversité des P. syringae rencontrés dans 36 vergers d’abricotiers de la vallée du Rhône, où le chancre bactérien était présent, et ce dans différents compartiments : le sol, le couvre-sol, les débris de culture, la plante (greffon) à différents stades de son développement, les racines (porte-greffe), la plante avec ou sans symptômes déclarées. Les résultats obtenus montrent que, parmi les 2436 isolats collectés, les isolats potentiellement pathogènes proviennent de 4 phylogroupes différents qui montrent une grande diversité; par ailleurs, certains phylogroupes sont ubiquistes et d’autres spécialisés. Le sol, le couvre-sol, les débris de culture, la plante (avec ou sans symptômes visibles) sont des réservoirs potentiels de la maladie. Les conséquences en termes d’étiologie et détection du chancre bactérien de l’abricotier sont discutées.

Le groupe des Pseudomonas syringae est très divers, au niveau phénotypique, génétique et de ses habitats. Récemment, 13 phylogroupes et 23 clades qui prennent en compte la diversité génétique et celle des habitats de cette bactérie ubiquiste ont été décrits (Berge et al., 2014). Des outils moléculaires permettant d’identifier les P. syringae et leur phylogroupes ont été développés au laboratoire (Borschinger et al., soumis), et nous permettent de travailler sur de relativement grands effectifs d’isolats bactériens. Avec ces outils, en réalisant nous-même des prélèvements dans des vergers ciblés en 2014 et 2015, et en collaboration avec le CTIFL qui a réalisé deux importantes prospections en 2011-2012, nous avons exploré la diversité des P. syringae rencontrés dans 36 vergers d’abricotiers de la vallée du Rhône, où le chancre bactérien était présent, et ce dans différents compartiments : le sol, le couvre-sol, les débris de culture, la plante (greffon) à différents stades de son développement, les racines (porte-greffe), la plante avec ou sans symptômes déclarées. Les résultats obtenus montrent que, parmi les 2436 isolats collectés, les isolats potentiellement pathogènes proviennent de 4 phylogroupes différents qui montrent une grande diversité; par ailleurs, certains phylogroupes sont ubiquistes et d’autres spécialisés. Le sol, le couvre-sol, les débris de culture, la plante (avec ou sans symptômes visibles) sont des réservoirs potentiels de la maladie. Les conséquences en termes d’étiologie et détection du chancre bactérien de l’abricotier sont discutées.

Lolium x Festuca hybrids (so-called Festulolium) renews considerably grass breeding in conjunction to the development of new genomic technology, the context of the climate change and the stressing injunction towards the breeders to release better adapted cultivars. This presentation points out some of those issues from a field trial carried out across the Eucarpia network and underlines how molecular genotyping could be essential to tackle the challenge.As hybrids between parental species quite differently adapted, Festulolium enlarge extensively genetic variability for many traits simultaneously. Two genome sources of genetic variability mix their effects within Festulolium hybrids. Thanks to preferential homologous chromosome pairing, strong linkage disequilibrium between parent species is mostly preserved within amphiploid hybrids. This contributes to maintain at intermediate level many traits simultaneously, of immediate overall advantage compared to parent species. Many experimental evidences then show that the gain of amphiploids tends to decrease as the number of generations following primary hybridization increases. When going through introgression stages into either parent species, the loss of effect on the phenotype is even more pronounced. Everything happens as if early large phenotype effects would result only from initial linkage disequilibrium, essentially at chromosome level. Thus, the exceptional high rate of homeologous recombination between Lolium and Festuca could make uneasy the retention of high linkage disequilibrium through long term selection and the recovery of substantial genetic progress.On the other hand, high heterozygosity rate due to high level of interspecific recombination could be favourable per se to stabilize Festulolium performances across years and environments, in other words, for more resilience. Thus, a better evaluation of interspecific linkage disequilibrium appears to be of crucial importance both in terms of breeding methods and breeding objectives. The challenge of breeding Festulolium may return simply to how better monitor the interspecific recombination in accordance to the objectives, either promoting it for more resilience, or fixing it at a given stage of a breeding process to take advantage of optimum Lolium-Festuca linkage disequilibrium for a given forage usage or local climate conditions.The new technology of genotyping by sequencing (GBS) has clearly this ability to assist Festulolium breeding. Genotype of individual plant as well as allele frequency in population can be assigned at thousands of single nucleotide polymorphic (SNP) loci throughout the genome, giving also access to allele dosage in polyploids which are frequent in Festulolium. In addition to the estimation of the average introgression rate among various Festulolium derivatives, GBS has also the stimulating perspective to estimate the true breeding value of traits of adaptation and how each Lolium vs Festuca genome counterpart may contribute for more precise breeding.

Lolium x Festuca hybrids (so-called Festulolium) renews considerably grass breeding in conjunction to the development of new genomic technology, the context of the climate change and the stressing injunction towards the breeders to release better adapted cultivars. This presentation points out some of those issues from a field trial carried out across the Eucarpia network and underlines how molecular genotyping could be essential to tackle the challenge.As hybrids between parental species quite differently adapted, Festulolium enlarge extensively genetic variability for many traits simultaneously. Two genome sources of genetic variability mix their effects within Festulolium hybrids. Thanks to preferential homologous chromosome pairing, strong linkage disequilibrium between parent species is mostly preserved within amphiploid hybrids. This contributes to maintain at intermediate level many traits simultaneously, of immediate overall advantage compared to parent species. Many experimental evidences then show that the gain of amphiploids tends to decrease as the number of generations following primary hybridization increases. When going through introgression stages into either parent species, the loss of effect on the phenotype is even more pronounced. Everything happens as if early large phenotype effects would result only from initial linkage disequilibrium, essentially at chromosome level. Thus, the exceptional high rate of homeologous recombination between Lolium and Festuca could make uneasy the retention of high linkage disequilibrium through long term selection and the recovery of substantial genetic progress.On the other hand, high heterozygosity rate due to high level of interspecific recombination could be favourable per se to stabilize Festulolium performances across years and environments, in other words, for more resilience. Thus, a better evaluation of interspecific linkage disequilibrium appears to be of crucial importance both in terms of breeding methods and breeding objectives. The challenge of breeding Festulolium may return simply to how better monitor the interspecific recombination in accordance to the objectives, either promoting it for more resilience, or fixing it at a given stage of a breeding process to take advantage of optimum Lolium-Festuca linkage disequilibrium for a given forage usage or local climate conditions.The new technology of genotyping by sequencing (GBS) has clearly this ability to assist Festulolium breeding. Genotype of individual plant as well as allele frequency in population can be assigned at thousands of single nucleotide polymorphic (SNP) loci throughout the genome, giving also access to allele dosage in polyploids which are frequent in Festulolium. In addition to the estimation of the average introgression rate among various Festulolium derivatives, GBS has also the stimulating perspective to estimate the true breeding value of traits of adaptation and how each Lolium vs Festuca genome counterpart may contribute for more precise breeding.

EUCLID is a project funded by the EU in the context of H2020. The objective of the EUCLID project is to contribute to secure the production of food for the increasing worldwide population while developing sustainable production approaches to be used in the European and Chinese agriculture. The project will exploit knowledge developed in the last decades and will explore new methods of IPM to provide solutions to pest management for specific problems of European and Chinese farmers for a few important and emblematic crops that represent different production systems. These include leafy vegetables, table and wine grapes and tomatoes. These crops also represent different production systems. As one of the partners of the EUCLID consortium, the MISTRAL team at INRA-Avignon will contribute its experience in the development of biological control agents of diseases of fruit and vegetable crops and in elucidating life history and evolutionary ecological processes that can be leveraged to innovate new means to manage plant health that are compatible with sustainable agriculture and agro-ecological principles. We will present the objectives and workpackages of EUCLID and the research that the MISTRAL team will develop pertinent to the management of fungal and bacterial diseases of the model crops of this project.

EUCLID is a project funded by the EU in the context of H2020. The objective of the EUCLID project is to contribute to secure the production of food for the increasing worldwide population while developing sustainable production approaches to be used in the European and Chinese agriculture. The project will exploit knowledge developed in the last decades and will explore new methods of IPM to provide solutions to pest management for specific problems of European and Chinese farmers for a few important and emblematic crops that represent different production systems. These include leafy vegetables, table and wine grapes and tomatoes. These crops also represent different production systems. As one of the partners of the EUCLID consortium, the MISTRAL team at INRA-Avignon will contribute its experience in the development of biological control agents of diseases of fruit and vegetable crops and in elucidating life history and evolutionary ecological processes that can be leveraged to innovate new means to manage plant health that are compatible with sustainable agriculture and agro-ecological principles. We will present the objectives and workpackages of EUCLID and the research that the MISTRAL team will develop pertinent to the management of fungal and bacterial diseases of the model crops of this project.

Sclérolèg est un projet financé par le CASDAR et labellisé par le GIS PIClég associant des partenaires publics de recherche et techniques privés ayant pour objectif de proposer des méthodes alternatives de protection contre Sclerotinia sclerotiorum, agent de la pourriture blanche sur 400 espèces végétales. En effet, il n’existe pas de moyens de protection chimique efficaces ni de résistance totale des variétés contre ce champignon. Afin de mieux intégrer et combiner les pratiques, le projet propose notamment de clarifier l’origine de l’inoculum primaire (air, sol), d’estimer une éventuelle spécialisation d’hôte du champignon et enfind’évaluer la variabilité de sa sensibilité à l’agent de lutte biologique Coniothyrium minitans.[br/]Une collection de souches de S. sclerotiorum isolées de plantes (notamment melon, carotte, haricot et endive) mais également de prélèvements d’air et de sclérotes dans le sol, au sud et au nord de la France, a été constituée grâce à tous les partenaires du projet. Les souches sont génotypées à l’aide de 16 marqueurs microsatellites et un sous ensemble est phénotypé pour les caractères tels que la vitesse de croissance mycélienne, la capacité à produire des sclérotes, l’agressivité sur plante et la sensibilité à C. minitans.[br/]Les premiers résultats montrent une présence pratiquement continue d’inoculum dans l’air au-dessus des cultures de carottes, endives et melons. L’absence de différentiation génétique significative entre les souches prélevées sur plantes de melon et celles prélevées dans l’air sur des parcelles de melon, va dans le sens d’une origine aérienne de l’inoculum engendrant les symptômes. Ceci est renforcé par l’existence d’haplotypes communs aux deux groupes de souches. L’analyse de souches telluriques, issues de sclérotes devraient affinercette observation. Les premiers résultats de phénotypage montrent des différences significatives de vitesse de croissance mycélienne et du nombre de sclérotes produits entre les 66 souches testées. En revanche, ils ne montrent pas de différence significative d’agressivité sur tomate, laitue et melon selon l’hôte d’origine des souches, ce qui va dans le sens d’une absence de spécialisation d’hôte. L’évaluation de la sensibilité à C. minitans est en cours.

Sclérolèg est un projet financé par le CASDAR et labellisé par le GIS PIClég associant des partenaires publics de recherche et techniques privés ayant pour objectif de proposer des méthodes alternatives de protection contre Sclerotinia sclerotiorum, agent de la pourriture blanche sur 400 espèces végétales. En effet, il n’existe pas de moyens de protection chimique efficaces ni de résistance totale des variétés contre ce champignon. Afin de mieux intégrer et combiner les pratiques, le projet propose notamment de clarifier l’origine de l’inoculum primaire (air, sol), d’estimer une éventuelle spécialisation d’hôte du champignon et enfind’évaluer la variabilité de sa sensibilité à l’agent de lutte biologique Coniothyrium minitans.[br/]Une collection de souches de S. sclerotiorum isolées de plantes (notamment melon, carotte, haricot et endive) mais également de prélèvements d’air et de sclérotes dans le sol, au sud et au nord de la France, a été constituée grâce à tous les partenaires du projet. Les souches sont génotypées à l’aide de 16 marqueurs microsatellites et un sous ensemble est phénotypé pour les caractères tels que la vitesse de croissance mycélienne, la capacité à produire des sclérotes, l’agressivité sur plante et la sensibilité à C. minitans.[br/]Les premiers résultats montrent une présence pratiquement continue d’inoculum dans l’air au-dessus des cultures de carottes, endives et melons. L’absence de différentiation génétique significative entre les souches prélevées sur plantes de melon et celles prélevées dans l’air sur des parcelles de melon, va dans le sens d’une origine aérienne de l’inoculum engendrant les symptômes. Ceci est renforcé par l’existence d’haplotypes communs aux deux groupes de souches. L’analyse de souches telluriques, issues de sclérotes devraient affinercette observation. Les premiers résultats de phénotypage montrent des différences significatives de vitesse de croissance mycélienne et du nombre de sclérotes produits entre les 66 souches testées. En revanche, ils ne montrent pas de différence significative d’agressivité sur tomate, laitue et melon selon l’hôte d’origine des souches, ce qui va dans le sens d’une absence de spécialisation d’hôte. L’évaluation de la sensibilité à C. minitans est en cours.