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Traditional agrosystems, where humans, crops and microbes have coevolved over long periods, can serve as models to understand the ecoevolutionary determinants of disease dynamics and help the engineering of durably resistant agrosystems. Here, we investigated the genetic and phenotypic relationship between rice (Oryza sativa) landraces and their rice blast pathogen (Pyricularia oryzae) in the traditional Yuanyang terraces of flooded rice paddies in China, where rice landraces have been grown and bred over centuries without significant disease outbreaks. Analyses of genetic subdivision revealed that indica rice plants clustered according to landrace names. Three new diverse lineages of rice blast specific to the Yuanyang terraces coexisted with lineages previously detected at the worldwide scale. Population subdivision in the pathogen population did not mirror pattern of population subdivision in the host. Measuring the pathogenicity of rice blast isolates on landraces revealed generalist life history traits. Our results suggest that the implementation of disease control strategies based on the emergence or maintenance of a generalist lifestyle in pathogens may sustainably reduce the burden of disease in crops.

Background: Gari and eba, forms of cassava semolina, are mainly consumed in Nigeria and other West African countries. This study aimed to define the critical quality traits of gari and eba, to measure their heritability, to define medium and high throughput instrumental methods for use by breeders, and to link the traits with consumer preferences. The definition of a food product's profiles, including its biophysical, sensory, and textural qualities, and the identification of the characteristics that determine its acceptability, are important if new genotypes are to be adopted successfully. Results: Eighty cassava genotypes and varieties (three different sets) from the International Institute of Tropical Agriculture (IITA) research farm were used for the study. Participatory processing and consumer testing data on different types of gari and eba products were integrated to prioritize the traits preferred by processors and consumers. The color, sensory, and instrumental textural properties of these products were determined using standard analytical methods, and standard operating protocols (SOPs) developed by the RTBfoods project (Breeding Roots, Tubers, and Banana Products for End-user Preferences, https://rtbfoods.cirad.fr). There were significant (P

Adapting to climate change in vulnerable coffee regions is crucial to maintain rural livelihoods. Among the solutions, coffee breeding strategies aim to produce coffee varieties with higher output performance than traditional varieties while reducing competition for land. This paper investigates the output performance of hybrid coffee (e.g., Starmaya and Centroamericano – H1), introgressed (e.g., Marsellesa and obatá) and traditional coffee (e.g., Caturra and Villa Sarchi) varieties. By using plot-level panel data among commercial farms in Costa Rica, we estimate the output performance of the three coffee varieties using pooled ordinary least squares and random effects models. We find that hybrid coffee varieties give 29-61% higher output than traditional coffee varieties. The results remain robust even after controlling for factor and climate inputs. Notwithstanding the larger productivity, hybrid coffee varieties demand more labor and inorganic fertilizers. While pesticide use may be reduced by hybrid's pest resistance, agroecological approaches for nutrient management are still needed to improve livelihoods and environmental outcomes. Headed towards longer-term studies, our paper presents the first evidence on the output performance of hybrid coffee varieties outside on-farm trials or experimental plots. These results suggest the potential of hybrid coffee varieties in promoting sustainable agriculture by improving the livelihood of coffee farmers, enhancing their adaptation against climate change and decreasing competition for land.

International audience; Increasing the cultivated diversity has been identified as a major leverage for the agroecological transition as it can help improve the resilience of low input cropping systems. For wheat, which is the most cultivated crop worldwide in terms of harvested area, the use of cultivar mixtures is spreading in several countries, but studies have seldom focused on establishing mixing rules based on plant architecture. Yet, the aerial architecture of plants and the overall canopy structure are critical for field performance as they greatly influence light interception, plant interactions and yield. The very high number of trait combinations in wheat mixtures makes it difficult to conduct experimentations on this issue, which is why a modeling approach appears to be an appropriate solution. In this study, we used WALTer, a functional structural plant model (FSPM), to simulate wheat cultivar mixtures and try to better understand how differences between cultivars in key traits of the aerial architecture influence mixture performance. We simulated balanced binary mixtures of cultivars differing for different critical plant traits: final height, leaf dimensions, leaf insertion angle and tillering capability. Our study highlights the impact of the leaf dimensions and the tillering capability on the performance of the simulated mixtures, which suggests that traits impacting the plants' leaf area index (LAI) have more influence on the performance of the stand than traits impacting the arrangement of the leaves. Our results show that the performance of mixtures is very variable depending on the values of the explored architectural traits. In particular, the best performances were achieved by mixing cultivars with different leaf dimensions and different tillering capability, which is in agreement with numerous studies linking the diversity of functional traits in plant communities to their productivity. However, some of the worst performances were also achieved by mixing varieties differing in their aerial architecture, which suggests that diversity is not a sufficient criterion to design efficient mixtures. Overall, these results highlight the importance of simulation-based explorations for establishing assembly rules to design efficient mixtures.

International audience; Orange rust of sugarcane caused by Puccinia kuehnii was first reported in Florida in 2007. Since then, several sugarcane cultivars that were resistant during the initial epidemics became susceptible within a few years. These shifts in resistance were attributed to the evolution of the pathogen and appearance of new races. To study the variation in virulence of P. kuehnii, healthy leaf pieces of sugarcane cultivars susceptible to orange rust were brush inoculated with isolates of P. kuehnii collected from susceptible cultivars in the field. After inoculation, leaf pieces were placed in an incubator and disease severity based on the number of rust uredinia was determined 2 weeks postinoculation. Isolates of P. kuehnii collected from sugarcane cultivar CP 89-2143, which only showed severe symptoms of orange rust starting in 2011-2012, produced 300%-500% more uredinia on CP 89-2143 than the isolates collected from cultivar CL 85-1040 that has been susceptible since 2007. Sugarcane cultivar CL 85-1040 exhibited high and equivalent numbers of uredinia regardless of the inoculated isolate of the pathogen. These data support the occurrence of pathogenic specialization within P. kuehnii and the existence of at least two races of this pathogen in Florida. Analysis of amplified fragment-length polymorphism among isolates of P. kuehnii from cultivars CP 89-2143 and CL 85-1040 differing in resistance to orange rust revealed genetic variation among rust uredinia. However, this variation was not associated with a specific sugarcane cultivar, suggesting that pathogenic variation was not linked to major, but rather to small genetic changes within the genome of P. kuehnii.

All over the world, sugarcane breeding programs are developing new, high-yielding cultivars that are resistant to major diseases to improve the profitability and sustainability of the sugar-energy industries they serve. In Reunion Island, sugarcane genetic improvement efforts began in 1929. Many challenges had to be overcome. Continuous breeding efforts have been made to develop varietal resistances to control some major diseases and are still going on today. Given the extreme agroclimatic diversity that characterizes the different production areas of the industry, it was necessary to gradually develop a large network of seven decentralized breeding programs to support genetic progress throughout the whole industry. This article provides an overview of the sugarcane breeding program of Reunion. It describes historical achievements and gives detailed information about germplasm development, variety exchanges, breeding program and selection scheme and procedures. A review is also made on applied genetics research activities supporting variety improvement. Further progress depends on the optimized functioning of the current breeding program, which has never been so largely extended in terms of target environments. The article discusses prospects of genomics breeding applications in the complex genetic context of sugarcane, which will require large multidisciplinary collaborations.

International audience; Arbuscular mycorrhizal (AM) fungi constitute promising biofertilizers for the deployment of a sustainable agriculture. However, the evaluation of mycorrhizal benefits in the field is poorly documented, notably in fruit tree orchards, and concerns exclusively growth performance and nutrition. Here, we evaluated the persistence of beneficial effects of AM fungal inoculation on two jujube (Ziziphus mauritiana Lam.) cultivars (Tasset and Gola) inoculated in nursery conditions and subsequently transferred in the field until fruit production. The growth-promoting effects on jujube observed in nursery was still maintained 18 months after planting, with significant higher rates of survival and an increase of fruit production for inoculated jujube cultivars. Nevertheless, AM-mediated responses were dependent on cultivar. No major disturbance of native AM fungal community was associated with AM fungal inoculation but a stimulation of AM fungal colonization is probable. The use of mycorrhizal inoculation with the R. irregularis IR27 strain hold promise for the development of efficient jujube orchards under semi-arid conditions.

The diversity of both bacterial and fungal communities associated with mango surface was explored using a metabarcoding approach targeting fungal ITS2 and bacterial 16S (V3-V4) genomic regions. Fruits were collected in Reunion Island from two different orchards according to a sampling method which allowed the effect of several pre-harvest factors such as geographical location (terroir), cultivars, fruit parts, tree position in the plot, fruit position on the tree (orientation and height), as well as the harvest date to be investigated. A total of 4,266,546 fungal and 2,049,919 bacterial reads were recovered then respectively assigned to 3,153 fungal and 24,087 to bacterial amplicon sequence variants (ASVs). Alpha and beta diversity, as well as differential abundance analyses revealed variations in both bacterial and fungal communities detected on mango surfaces depended upon the studied factor. Results indicated that Burkholderiaceae (58.8%), Enterobacteriaceae (5.2%), Pseudomonadaceae (4.8%), Sphingomonadaceae (4.1%), Beijerinckiaceae (3.5%), and Microbacteriaceae (3.1%) were the dominant bacterial families across all samples. The majority of fungal sequences were assigned to Mycosphaerellaceae (34.5%), Cladosporiaceae (23.21%), Aureobasidiaceae (13.09%), Pleosporaceae (6.92%), Trichosphaeriaceae (5.17%), and Microstromatales_fam_Incertae_sedis (4.67%). For each studied location, mango fruit from each cultivar shared a core microbiome, and fruits of the same cultivar harvested in two different locations shared about 80% fungal and bacterial family taxa. The various factors tested in this study affected bacterial and fungal taxa differently, suggesting that some taxa could act as geographical (terroir) markers and in some cases as cultivar fingerprints. The ranking of the factors investigated in the present study showed that in decreasing order of importance: the plot (terroir), cultivar, fruit parts, harvest date and the position of the fruits are respectively the most impacting factors of the microbial flora, when compared to the orientation and the fruit position (height) on the tree. Overall, these findings provided insights on both bacterial and fungal diversity associated with the mango surface, their patterns from intra-fruit scale to local scale and the potential parameters shaping the mango microbiota.

International audience

International audience; Rainfed crop production predominates in West Africa. Rice is an important staple food, especially in Senegal. The scope for increase in rice production under irrigated conditions is uncertain. Rainfed rice is therefore a key component for regional food security impelling agronomists to assess climate change impact on rainfed rice yield and to design rainfed rice ideotypes suited to future climate scenarios. The DSSAT CSM-CERES-Rice model was thus calibrated and evaluated on 19 agronomic experiments conducted in 2012, 2013, and 2014, in 6 locations, with 21 cultivars and two fertilization levels (20 and 80 kg N ha−1). Simulations were then carried out with the crop model forced with the downscaled projections of seven climate models, with and without considering the impact of an increase in atmospheric [CO2], using an ensemble of global circulation models and two Representative Concentration Pathways (RCP2.6 and RCP8.5). Simulated rice yield was divided by two over the century with RCP8.5 and stagnated with RCP2.6. Elevated [CO2] significantly increased yields, but this effect could not offset the yield decline due to elevated temperatures. Cultivars with longer vegetative phases and greater temperature tolerance were better adapted to climate change than current cultivars. Using these new cultivars with the recommended fertilization rate (80 kg N ha−1) could offset the yield decline due to climate change. For the first time, we bring together a study based on a process-based crop model handling crop response to elevated [CO2], a large set of field experiments and up-to-date climate projections (i) to provide useful insights into plausible impacts of climate change on rainfed rice in Senegal and (ii) to identify cultivar characteristics relevant for adaptation to future possible climates. Our findings will help set priorities for breeding resilient cultivar in the region.

Cacao (Theobroma cacao L.) is an important Neotropical crop originating in South America and dispersed by European explorers, arriving in Madagascar in the late 19th century. Although Madagascar is an important producer of cocoa for the premium chocolate market, the varietal composition and genetic diversity in cacao germplasm from Madagascar, especially in traditional cacao farms, remains unknown. A total of 190 cacao accessions, including 40 farmer accessions collected from traditional cacao farms in Madagascar, and 150 accessions representing seven reference cacao populations, were analyzed using Single Nucleotide Polymorphism (SNP) markers. Multivariate analysis and Bayesian stratification resulted in the clustering of the 40 farmer accessions into three groups: Criollo, Amelonado and Trinitario. These three traditional varieties were commonly cultivated in tropical America in the 18th century, but most of them have been replaced by improved varieties. The present study demonstrated that Madagascar is distinctive in that all three traditional cacao varieties, Criollo, Amelonado and Trinitario, are still maintained on-farm for cocoa production, as in Mesoamerica and the Caribbean several hundred years ago. Results from the present study are significant in terms of understanding the early dispersal of cacao from tropical America and Asia to Africa, in addition to the well-documented route from Brazil to São Tomé & Príncipe. The results also provide new information for planning future conservation and utilization of cacao germplasm in Madagascar.

This review of the literature on varietal change in sub-Saharan Africa looks in detail at adoption of new varieties of bananas in Uganda, cassava in Nigeria, potato in Kenya, sweetpotato in Uganda and yams in C^ote d'Ivoire. The review explored three hypotheses about drivers of varietal change. There was a strong confirmation for the hypothesis that insufficient priority given to consumer-preferred traits by breeding programmes contributes to the limited uptake of modern varieties (MVs) and low varietal turnover. Lack of evidence meant the second hypothesis of insufficient attention to understanding and responding to gender differences in consumer preferences for quality and post-harvest traits was unresolved. The evidence on the third hypothesis about the informal seed system contributing to slow uptake of MVs was mixed. In some cases, the informal system has contributed to rapid uptake of MVs, but often it appears to be a barrier with inconsistent varietal naming a major challenge.

So far, the main Arabica coffee breeding programmes in Latin America have focused on the selection of varieties adapted to intensive full-sun farming systems. Meanwhile, little attention has been paid to breeding varieties specifically adapted to shade, which is the main characteristic of agroforestry systems (AFS). Yet the specialty coffee sector is currently expanding and seeking specific sensory qualities related to exotic varieties and no breeding programme exists to create new varieties for this type of market. Two trials were set up: one in full sun and the other under shade. F1 hybrids and their parents (pure lines and Ethiopian accessions) were studied in a factorial-crossing design to measure tree volume, yield (3 years), bean size, the bean NIRS signature and the final cupping score. Bean size and the final cupping score seemed to be relatively unaffected by shading. Strong maternal heritability was observed for bean size. In the trials, F1 hybrids produced “75–80%” more than the maternal lines and “40–50%” more than the male parents in the shade trial and in the full-sun trial, respectively. By choosing the F1 hybrid, it is possible to increase productivity under both shade and full sun while simultaneously achieving good sensory qualities. Selecting a F1 hybrid for “specialty coffee” seems exceptional. This raises a fundamental issue concerning the maternal heritability of seed biochemical composition. We conclude that selection under shade is essential for the selection of varieties adapted to AFS.

International audience; Self-incompatibility is an important evolutionary feature in angiosperms and has major implications for breeding strategies in horticultural crops. In citrus, when coupled with parthenocarpy, it enables the production of seedless fruits in a mono-varietal orchard. A gametophytic incompatibility system with one S locus was proposed for citrus, but its molecular mechanisms remain the subject of debate. The objective of this work was to locate the S locus by the analyzing segregation distortion in reciprocal crosses of two self-incompatible citrus sharing one self-incompatible allele and to compare this location with previously published models. High density genetic maps of ‘Fortune’ mandarin and ‘Ellendale tangor’ with, respectively, 2164 SNP and 1467 SNP markers, were constructed using genotyping by sequencing data. They are highly syntenic and collinear with the clementine genome. Complete rejection of one allele was only observed in male segregation in the two parents and in only one genomic area, at the beginning of chromosome 7 of the clementine reference genome. Haplotype data in the area surrounding the theoretical S locus were in agreement with previously proposed S genotypes. Overall, our results are in full agreement with the recently proposed gametophytic S-RNase system with the S locus at the beginning of chromosome 7 of the clementine reference genome.

International audience; In Reunion Island, new sugarcane commercial varieties selected for constrained environments, particularly with regard to low temperatures, have demonstrated their better adaptability by producing more biomass in the high-lying parts of the island. The germination dynamics of populations of single bud setts were studied and characterized in growth chambers for three contrasting varieties at different constant temperatures. The emergence of setts as a function of time is faster and more complete for the variety R583, which is known to be better adapted to low temperatures than for R570 and R577. Does the variety R583 selected under temperature constrained environment performs better under such conditions as a result of its lower threshold temperature for germination? The objectives of our study were (i) to characterize the germination performance of three varieties under different temperature regimes, and (ii) to illustrate in the field the important simulated results obtained with the help of mapping tools. A germination non-linear mixed model with random effects was developed from the degree-days data. This Weibull equation made it possible to determine a threshold temperature for the germination process for each variety. Taking into account the germination threshold temperature obtained, a simulation of the germination times was carried out per zone, on the west coast of Reunion Island, based on climatic data over 10 years. The two-degree difference between the base temperatures of varieties R583 and R570 shows the relative importance of this parameter on germination date, suggesting that the plant is able to establish more quickly. A parallel was drawn between the geographical limits obtained, where the establishment of the variety R583 is possible regarding the time required for germination (in days) from the simulation and the actual spreading of this variety.

Stable and sufficient food supplies are increasingly threatened by climatic variability, in particular extreme heat events. Intraspecific crop diversity may be an important biological resource to both understand and maintain crop resilience to extreme conditions. Here using data from a mass field experiment screening for heat tolerance in sweet potato (Ipomoea batatas), we identify 132 heat-tolerant cultivars and breeding lines (6.7%) out of 1,973 investigated. Sweet potato is the world's fifth most important food crop, and mean conditions experienced by sweet potato by 2070 are predicted to be 1 to 6 degrees C warmer, negatively impacting most genotypes. We identify canopy temperature depression, chlorophyll content and storage root-flesh colour as predictors of heat tolerance and, therefore, as potential traits for breeding consideration. These results highlight the role of intraspecific biodiversity for the productivity and resilience of food and agricultural systems in the face of climate change. Mass field testing of heat tolerance in 1,973 cultivars of sweet potato (Ipomoea batatas) from 50 countries identifies tolerant cultivars and reveals tolerance-predictive traits for breeding consideration. The work highlights the role of intraspecific diversity for future crop resilience.

The adoption of new cultivars depends largely on the extent to which the breeding objectives set to identify the new cultivars align with the farmers' preferences. There is documented potential of improved cultivars to enhance productivity and income in the developing world, but their adoption among smallholders remains low. Here, we attempt to understand if in the case of Morocco the low level of adoption of new durum wheat (Triticum durum Desf.) cultivars can be partially explained by a misalignment of breeders objectives. Factorial analysis was applied to data obtained through a set of interviews with 90 wheat breeders from 49 countries and a case study of 861 durum wheat growers in Morocco, to reveal the existence of five breeders and four farmers classes based on relative importance assigned to five mega-traits: grain yield potential, yield stability, abiotic stress tolerance, biotic stress resistance, industrial quality, and household use. Weighted indexes were derived based on the average rate of preference shown by each interviewee belonging to that specific class, and hierarchically clustered to reveal poor matching between North African breeders and Moroccan farmers. Further, these indexes were applied to the actual performances of 23 durum wheat elite lines to reveal 71% to 87% matching. However, breeders' and farmers' classes had preferences for different genotypes. Together, these results indicate that a certain degree of misalignment exist between farmers and breeders' objectives, and that the use of participatory farmers-weighted indexes could help raise the level of adoption.

This work was conducted to study the performance of eight sorghum varieties that contrasted with intensified practices in the Sudano-Sahelian zone of Mali. Two experiments were carried out in 2018 and 2019 rainy seasons at Sotuba Agricultural Research Station in Mali. The experimental design used was a Split-split-plot with three replications and three factors including two plant densities (D1: 26666 plants ha-1 and D2: 53333 plants ha-1) as the main plot, three nitrogen levels (0, 41 and 82 kg N ha-1) as the subplot and varieties as the sub-subplot. Measurements focused on growth and physiological parameters, grain yield and yield components. The results showed that sorghum grain yield was positively correlated with straw yield, leaf area index, grain number per panicle, panicle number per m2, panicle weight per m2 in N0D1 (0 kg N ha-1 and 26666 plants ha-1) and N2D2 (178 kg N ha-1 and 53 333 plants ha-1). Furthermore, straw yield was positively correlated with the leaf area index and panicle weight m-² in N0D1 and in N2D2. Analysis of variance showed that plant density, nitrogen and variety effect on grain and straw yields were significant. The interaction density x nitrogen x variety effect was also significant on grain and straw yields. Grain and straw yields were high in the N2D2 treatment for eight varieties compared to the N0D1 treatment. GRINKAN, C2_075-15 and C2_007-03 varieties had the highest grain and straw yields in N0D1. These caudatum-type varieties could be recommended in less intensive sorghum production areas in Mali. The FADDA variety produced high grain and straw yields in N2D2. Guinea-type hybrid FADDA may be recommended for grain and straw production in intensive sorghum production areas in Mali.

International audience; This study aimed to understand the response of photosynthesis and growth to e-CO2 conditions (800 vs. 400 mu mol mol(-1)) of rice genotypes differing in source-sink relationships. A proxy trait called local C source-sink ratio was defined as the ratio of flag leaf area to the number of spikelets on the corresponding panicle, and five genotypes differing in this ratio were grown in a controlled greenhouse. Differential CO2 resources were applied either during the 2 weeks following heading (EXP1) or during the whole growth cycle (EXP2). Under e-CO2, low source-sink ratio cultivars (LSS) had greater gains in photosynthesis, and they accumulated less nonstructural carbohydrate in the flag leaf than high source-sink ratio cultivars (HSS). In EXP2, grain yield and biomass gain was also greater in LSS probably caused by their strong sink. Photosynthetic capacity response to e-CO2 was negatively correlated across genotypes with local C source-sink ratio, a trait highly conserved across environments. HSS were sink-limited under e-CO2, probably associated with low triose phosphate utilization (TPU) capacity. We suggest that the local C source-sink ratio is a potential target for selecting more CO2-responsive cultivars, pending validation for a broader genotypic spectrum and for field conditions.

Chocolate is a widely consumed product worldwide due to its exquisite flavor, which comes from the unique and fascinating cocoa flavor. This flavor depends on little controllable variables such as the genotype and the agroecological niche, and on the other side, on postharvest operations: (1) cocoa transformation from seeds to beans that comprises cocoa seeds preconditioning, fermentation, and drying, and (2) the production of chocolate from the bean in which roasting is highlighted. Postharvest transformation operations are critically important because during these, cocoa flavor is formed, allowing the differentiation of two categories: bulk and specialty cocoa. In this sense, this article presents an overview of cocoa postharvest operations, the variables and phenomena that influence and control the physical and biochemical transformation from seeds to cocoa beans, and their relation to the formation of chocolate flavor. Moreover, research perspectives in terms of control and management of postharvest practices in order to obtain cocoa with differentiated and specialty characteristics "from bean to bar" are discussed.

In the present paper, we evaluated the implementation of a seed production system based on the exploitation of male sterility on coffee. We studied specifically the combination between CIR-SM01 and Marsellesa® (a Sarchimor line), which provides a hybrid population called Starmaya. We demonstrated that the establishment of seed garden under natural pollination is possible and produces a sufficient amount of hybrid seeds to be multiplied efficiently and economically. As expected for F1 hybrid, the performances of Starmaya are highly superior to conventional cultivars. However, we observed some heterogeneity on Starmaya cultivar in the field. We confirmed by genetic marker analysis that the off-types were partly related to the heterozygosity of the CIR-SM01 clone and could not be modified. Regarding the level of rust resistance of Starmaya cv., we saw that it could be improved if Marsellesa was more fully fixed genetically. If so, we should be able to decrease significantly the percentage of rust incidence of Starmaya from 15 to 5%, which would be quite acceptable at a commercial level. Starmaya represents the proof of concept for the mass propagation of Arabica F1 hybrid seeds using male sterility. Finally, we discuss the possibility to increase the number of hybrid varieties produced by seed, exploring some initiatives to identify male sterility markers to induce male sterility on any conventional cultivar. This would definitively open up the universe of known Arabica cultivars to be used in breeding new F1 hybrids.

The purpose of this study was to explore the relations between certain dimensions of leisure practice and cognitive vitality in seniors and identify which of their sociodemographic and health characteristics (SHC) are related to leisure practice. A cross-sectional analysis of leisure practice, cognitive performance, self-perceived memory and SHC was performed among 294 French-speaking Canadian seniors attending community centres (255 women, average age: 71), by multiple linear regressions and partial correlations controlled for SHC. Outcomes from the project show that the diversity of leisure was related to the Montreal Cognitive Assessment and the California Verbal Learning Test, the frequency of cognitive leisure was associated to the Stroop Test, and the frequency of social leisure showed no significant association. “Paper and pencil games”, “computer use” and “helping a sibling” were related to various cognitive tests. Frequency of leisure (total) was related to gender and education, and diversity of leisure was related to education, age and depression. Study outcomes indicate that diversity of leisure was more related to cognitive vitality than frequency. Future studies should address leisure diversity as a way to promote cognitive vitality among seniors. Moreover, seniors’ characteristics should be considered when seeking to facilitate their participation in leisure activities., Le but de cette étude était d’explorer les relations entre certaines dimensions de la pratique de loisirs et la vitalité cognitive chez des aînés et d’identifier leurs caractéristiques sociodémographiques et de santé (CSS) qui étaient liées à leur pratique de loisirs. Une analyse transversale de la pratique de loisirs, de la performance cognitive, du niveau perçu de la mémoire et des CSS a été réalisée auprès de 294 aînés canadiens parlant français et qui participaient aux activités d’un centre communautaire (255 femmes, âge moyen : 71 ans), par des régressions linéaires multiples et des corrélations partielles contrôlées pour les CSS. Les résultats montrent que la variété des loisirs était liée au Montreal Cognitive Assessment et au California Verbal Learning Test, que la fréquence des loisirs cognitifs était associée au test de Stroop et que la fréquence des loisirs sociaux ne montrait aucune association. Les « jeux papier-crayon », « l’utilisation de l’ordinateur » et « prendre soin d’un proche » étaient reliés à plusieurs tests cognitifs. La fréquence totale des loisirs était liée au sexe et à l’éducation et la variété des loisirs était liée à l’éducation, à l’âge et à la dépression. Les résultats de cette étude montrent que la variété des loisirs était davantage liée à la vitalité comparée à la fréquence des loisirs. De futures études devraient aborder la variété des loisirs comme une manière de promouvoir la vitalité cognitive chez les aînées. De plus, les caractéristiques des aînés devraient être considérées afin de favoriser leur participation aux activités de loisirs dans les centres communautaires.

The aim of this study was to determine differences in grazing efficiency between varieties of perennial ryegrass (Lolium perenne L.) and to determine varietal traits influencing grazing efficiency. Grazing efficiency refers to the proportion of leaf tissue that is removed, relative to the amount presented to the animals prior to grazing. Low post-grazing sward heights are desirable as they condition the sward to increase leaf production and thus reduce the proportion of stem in the sward in subsequent rotations. Thirty varieties of perennial ryegrass from the Irish Recommended List were studied. The plots were grazed on nineteen occasions over two years, 2017 and 2018. Pre-grazing sward height, post-grazing sward height, herbage production, nutritive quality and morphology were measured throughout the trial. Varieties differed in their level of grazing efficiency (P