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A genome-wide association study for pea resistance against a pea-adapted biotype and a non-adapted biotype of the aphid, Acyrthosiphon pisum, identified a genomic region conferring resistance to both biotypes. In a context of reduced insecticide use, the development of cultivars resistant to insect pests is crucial for an integrated pest management. Pea (Pisum sativum) is a crop of major importance among cultivated legumes, for the supply of dietary proteins and nitrogen in low-input cropping systems. However, yields of the pea crop have become unstable due to plant parasites. The pea aphid (Acyrthosiphon pisum) is an insect pest species forming a complex of biotypes, each one adapted to feed on one or a few related legume species. This study aimed to identify resistance to A. pisum and the underlying genetic determinism by examining a collection of 240 pea genotypes. The collection was screened against a pea-adapted biotype and a non-adapted biotype of A. pisum to characterize their resistant phenotype. Partial resistance was observed in some pea genotypes exposed to the pea-adapted biotype. Many pea genotypes were completely resistant to non-adapted biotype, but some exhibited partial susceptibility. A genome-wide association study, using pea exome-capture sequencing data, enabled the identification of the major-effect quantitative trait locus ApRVII on the chromosome 7. ApRVII includes linkage disequilibrium blocks significantly associated with resistance to one or both of the two aphid biotypes studied. Finally, we identified candidate genes underlying ApRVII that are potentially involved in plant-aphid interactions and marker haplotypes linked with aphid resistance. This study sets the ground for the functional characterization of molecular pathways involved in pea defence to the aphids but also is a step forward for breeding aphid-resistant cultivars.

International audience

National audience; Le pois (Pisum sativum) constitue une culture d’importance majeure parmi les légumineuses pour ses qualités de plante protéagineuse, notamment en Europe en réduisant la part de protéines végétales importées ainsi que pour son rôle dans la rotation des cultures en fixant l’azote atmosphérique dans le sol. Cependant, ces dernières années, les rendements ont été rendus instables dus aux contraintes biotiques et abiotiques. Pour lutter contre certains ravageurs, les producteurs ont recours à de grandes quantités de pesticides qui sont coûteuses et dangereuses pour l’environnement et la santé humaine. Pour ces raisons, des alternatives sont mises en œuvre tels que le développement de stratégies d’utilisation et de gestion des résistances génétiques. Le puceron vert du pois (Acyrthosiphon pisum) est un ravageur important des cultures de légumineuses et créée des dommages directement en se nourrissant de la sève phloémienne au cours des périodes d’infestations et indirectement en étant vecteur de virus pathogènes. Cette espèce de puceron forme un complexe d'au moins 15 biotypes, chacun est adapté pour se nourrir sur une ou quelques espèces de légumineuses et révèle des performances réduites sur d'autres espèces. Nos travaux de recherche portent sur la compréhension des mécanismes génétiques et moléculaires des interactions plante-puceron conduisant à la résistance hôte et non-hôte des légumineuses face à A. pisum. Un phénotypage par test de fécondité de puceron sur plante a été réalisé pour déterminer les profils de résistance de 240 génotypes de pois face à deux biotypes d’A. pisum, l’un adapté et l’autre non-adapté au pois. Aucune résistante complète au biotype adapté d’A. pisum n’a été observée dans les accessions de pois , alors que de nombreuses accessions ont montré une résistance complète au biotype non-adapté. De plus, de grandes variations de niveaux de résistance quantitative ont été observées parmi les génotypes de pois face aux deux biotypes d'A. pisum. A partir de données de séquençage exome capture obtenues sur les 240 génotypes dans le cadre du projet PeaMUST, une approche de génétique d’association sur le génome entier (GWAS), a été réalisée afin d’identifier les déterminants génétiques de la résistance du pois aux deux biotypes d’A. pisum. Les résultats ont permis de mettre en évidence des loci significativement associés à la résistance du pois sur le chromosome 7, incluant des loci spécifiques de chacun des deux biotypes d’A. pisum, dont l’un présentant un effet majeur, et deux loci communs aux deux biotypes. Une analyse d’haplotypes dans les intervalles sous-jacents à ces loci a confirmé des différences significatives de phénotypes entre groupes de lignées partageant les mêmes haplotypes. Cette approche a permis d’identifier une liste de génotypes de pois dont les comportements de résistance seront confirmés au champ. Elle a permis d’identifier des loci et gènes candidats sous-jacents à valider expérimentalement pour leur implication dans la compatibilité et incompatibilité du pois aux différents biotypes d’A. pisum.

International audience; Our goal is to understand how dancers learn complex dance phrases. We ran three workshops where dancers learned dance fragments from videos. In workshop 1, we analyzed how dancers structure their learning strategies by decomposing movements. In workshop 2, we introduced MoveOn, a technology probe that lets dancers decompose video into short, repeatable clips to support their learning. This served as an effective analysis tool for identifying the changes in focus and understanding their decomposition and recomposition processes. In workshop 3, we compared the teacher's and dancers' decomposition strategies, and how dancers learn on their own compared to teacher-created decompositions. We found that they all ungroup and regroup dance fragments, but with different foci of attention, which suggests that teacher-imposed decomposition is more effective for introductory dance students, whereas personal decomposition is more suitable for expert dancers. We discuss the implications for designing technology to support analysis, learning and teaching of dance through movement decomposition.

Linkage disequilibrium (LD) decay in the pea-Aphanomyces collection. Coloured curves represent the estimated LD decay for each linkage group (LG). Dashed horizontal lines represent half of the maximum LD value (LD threshold=0.5). Arrows represent the LD decay rate, as the estimated genetic distance (cM) to drop to the LD threshold on each LG. (PDF 157 kb)

Clustered heatmap of correlation coefficients between disease resistance, earliness and height variables data. Variables are coded as described in Additional file 4. Only correlations with a p-value < 0.05 are shown. Colours represent level of correlation, coded as follow: dark red: r < −0.8; medium red: −0.8 < r < −0.5; light red: −0.5 < r < −0.2; white: −0.2 < r < 0.2 or p-value > 0.05; light green: 0.2 < r < 0.5; medium green: 0.5 < r < 0.8; dark green: r > 0.8. Clustering is based on the UPGMA method. (PDF 48 kb)

Frequency distribution of least square means obtained for Aphanomyces resistance, earliness and plant height in the pea-Aphanomyces collection. Least square means were obtained from analysis of variance for three Aphanomyces resistance traits (Root Rot Index, first and second Aerial Decline Indexes, coded RRI, ADI1 and ADI2, respectively), three earliness traits (dates to 50 % bloom, 100 % bloom and 100 % dried plants, coded FLO1, FLO2 and RIPE, respectively) and plant height (HT). Aphanomyces resistance traits were assessed over nine infested field environments and against two reference strains of A. euteiches (RB84 and Ae109) in controlled conditions. Earliness and height were assessed in two healthy environments. n: total number of pea lines assessed; m: mean ± standard deviation of the pea-Aphanomyces collection; h2: mean-based heritability. (PDF 38 kb)

Clustered heatmap of the Kinship matrix. Kinship matrix from the GAPIT R package [75] based on 2937 SNP markers. Clustering is based on the UPGMA method. Colours represent the degree of relationship between two given lines. Pea line information is described as in Additional file 1. Lines sharing same pedigree or end use or sowing type are well clustered thus the Kinship matrix efficiently represents the relationships between individuals. (PDF 1253 kb)

Background Genome-wide association (GWA) mapping has recently emerged as a valuable approach for refining the genetic basis of polygenic resistance to plant diseases, which are increasingly used in integrated strategies for durable crop protection. Aphanomyces euteiches is a soil-borne pathogen of pea and other legumes worldwide, which causes yield-damaging root rot. Linkage mapping studies reported quantitative trait loci (QTL) controlling resistance to A. euteiches in pea. However the confidence intervals (CIs) of these QTL remained large and were often linked to undesirable alleles, which limited their application in breeding. The aim of this study was to use a GWA approach to validate and refine CIs of the previously reported Aphanomyces resistance QTL, as well as identify new resistance loci. Methods A pea-Aphanomyces collection of 175 pea lines, enriched in germplasm derived from previously studied resistant sources, was evaluated for resistance to A. euteiches in field infested nurseries in nine environments and with two strains in climatic chambers. The collection was genotyped using 13,204 SNPs from the recently developed GenoPea Infinium® BeadChip. Results GWA analysis detected a total of 52 QTL of small size-intervals associated with resistance to A. euteiches, using the recently developed Multi-Locus Mixed Model. The analysis validated six of the seven previously reported main Aphanomyces resistance QTL and detected novel resistance loci. It also provided marker haplotypes at 14 consistent QTL regions associated with increased resistance and highlighted accumulation of favourable haplotypes in the most resistant lines. Previous linkages between resistance alleles and undesired late-flowering alleles for dry pea breeding were mostly confirmed, but the linkage between loci controlling resistance and coloured flowers was broken due to the high resolution of the analysis. A high proportion of the putative candidate genes underlying resistance loci encoded stress-related proteins and others suggested that the QTL are involved in diverse functions. Conclusion This study provides valuable markers, marker haplotypes and germplasm lines to increase levels of partial resistance to A. euteiches in pea breeding. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2429-4) contains supplementary material, which is available to authorized users.

Example of MLMM R package plot outputs for analysis of the MFA.Dim.1 variable. (A): Bonferroni correction of the highest marker p-value for each step of the forward and backward analysis. Optimal step (dashed blue vertical line) is determined as the largest stepwise mixed model regression in which all cofactors have –log10(p-value) above the mBonf threshold (dashed black horizontal line). (B): QQ-plot at the optimal step. (C): Partition of variance for each forward and backward step. Variance explained by population structure (PCA; grey); all markers used as cofactors (blue); Kinship matrix (green) and unexplained variance (= missing heritability; red). The dashed blue vertical line represents the optimal step according to mBonf threshold. (D) Genome-wide Manhattan plot without marker cofactors. The dotted line represents the multiple-Bonferroni threshold above which markers are considered as significant. (E): Genome-wide Manhattan plot at the optimal step with marker cofactors (4 red dots). The dotted line represents the multiple-Bonferroni threshold above which markers are considered as significant. (PDF 148 kb)

This study investigated reading and spelling difficulties in subjects with the juvenile form of myotonic dystrophy (MD). Twenty-three consecutive patients with juvenile MD who were referred to a special clinic were assessed for reading and spelling skills (phonological processing, word identification, narrative comprehension (two tasks), information seeking in a document (TV schedule), and spelling). Reading impairments were frequent (63–84% of the subjects being below the level of literacy depending on the tasks), even in subjects without mental retardation (22–66%) despite normal word identification scores. All but two subjects had spelling difficulties. The severity of these learning difficulties was correlated with longer mutation size and maternal transmission, but could not be related to phonological deficit, suggesting that other brain dysfunction might be involved (e.g., attention, working memory, naming speed, executive function). Children

Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; Partial resistances, often controlled by quantitative trait loci (QTL), are considered to be more durable than monogenic resistances. Therefore, a precursor to developing efficient breeding programs for polygenic resistance to pathogens should be a greater understanding of genetic diversity and stability of resistance QTL in plants. In this study, we deciphered the diversity and stability of resistance QTL to Aphanomyces euteiches in pea towards pathogen variability, environments and scoring criteria, from two new sources of partial resistance (PI 180693 and 552), effective in French and USA infested fields. Two mapping populations of 178 recombinant inbred lines each, derived from crosses between 552 or PI 180693 (partially resistant) and Baccara (susceptible), were used to identify QTL for Aphanomyces root rot resistance in controlled and in multiple French and USA field conditions using several resistance criteria. We identified a total of 135 additive-effect QTL corresponding to 23 genomic regions and 13 significant epistatic interactions associated with partial resistance to A. euteiches in pea. Among the 23 additive-effect genomic regions identified, five were consistently detected, and showed highly stable effects towards A. euteiches strains, environments, resistance criteria, condition tests and RIL populations studied. These results confirm the complexity of inheritance of partial resistance to A. euteiches in pea and provide good bases for the choice of consistent QTL to use in marker-assisted selection schemes to increase current levels of resistance to A. euteiches in pea breeding programs

Reading therapy has been shown to be effective in treating reading disabilities (RD) in dyslexic children, but little is known of its use in subjects with mild mental retardation (MR). Twenty adult volunteers, with both RD and mild MR, underwent 60 consecutive weeks in a cognitive remediation program, and were compared with 32 untreated control subjects. The experimental group showed a significant improvement in word identification, as measured byoral production ( p = 0.0004) or silent reading ( p = 0.023), and sentence comprehension ( p = 0.0002). Adults with MR appear to benefit from new approaches in the field of RD. # 2005 Elsevier Ltd. All rights reserved.

Objective. To assess the relationship between word identification and intelligence in adults with mild mental retardation (IQ Method. A standardized evaluation was administered to 67 adults with mild mental retardation. The evaluation included a psychiatric interview, the WAIS-R, and a 2-h interview with a speech therapist and reading tests. Results. Causes of mental retardation were diverse in the sample, and IQ scores ranged from 43 to 79 (mean score = 64). All subjects exhibited reading impairment, including 69% with severe impairment. No subject with an IQ score under 65 was able to perform adequately in the word identification tasks. Word identification was correlated with total and verbal IQ, but not with performance IQ. Conclusion. Our results suggest that, in contrast to subjects with normal intelligence, IQ score is correlated with reading in subjects with mild mental retardation. Finally, remediation should be preferentially implemented for subjects with IQ score greater than 65.