Construction de l'architecture et des composantes visuelles d'un buisson ligneux d'ornement : le rosier

Shrubs form a key plant model to meet social and environmentalconcerns. Usually transposed on the tree model, their architecturaldevelopment is still ill-known and understudied to address visualquality. To identify and anticipate such expectations, the visual qualitymanagement of ornamental plants through a multidisciplinarymethodology is proposed. It includes architecture of the plants withits phenotypic plasticity and their visual appearance perception.On a rose bush: Rosa hybrida L. ‘Radrazz’, this work shows howarchitectural analysis with its modeling tools, sensory evaluationand image analysis can form a coherent scientifi c framework toface up to such a purpose, and be transposed for other taxa. Onvirtual rose bushes, and real ones exposed to a light gradient, thevisual appearance can be characterized objectively by means ofsensory tests using rotating plant video at different stages.Thevideo stand enables a better mental representation of the plant 3Dby the subjects, leading to a more complete and reliable descriptionof the plant visual appearance; then to predict this descriptionthrough statistically integrated image analysis of multiple plantfacets. Some relevant architectural variables, with numerousequivalents, potentially interesting to study the architecturaldevelopment of bushes during their life cycle, enabled to predicteven explain how visual components were built for a cultivar. Fora better market responsiveness, this work lays the foundationfor drafting interactive decision and innovation support tools forbLes buissons ligneux forment un modèle végétal clé pour répondreaux préoccupations sociales et environnementales.Usuellement transposé sur le modèle arborescent, leur développementarchitectural reste encore peu compris et peu étudiéau regard de leur qualité visuelle. Pour cerner et anticiper cesattentes, une méthodologie pluridisciplinaire visant le managementde la qualité visuelle des plantes d’ornement est proposée.Elle intègre l’architecture des plantes avec sa plasticité phénotypiqueet la perception de leur apparence visuelle. Sur un rosierbuisson : Rosa hybrida L. ‘Radrazz’, l’étude montre commentl’analyse architecturale avec ses outils de modélisation, l’analysesensorielle et d’image peuvent former un cadre scientifi quecohérent visant cet objectif, et transposable à d’autres taxons.Sur rosiers virtuels, et réels exposés à un gradient lumineux, l’apparencevisuelle peut être caractérisée objectivement au moyend’épreuves sensorielles sur vidéode plante en rotation à différentsstades. La vidéo permet aux sujets une meilleure représentationmentale de la plante en 3D, et ainsi une descriptionplus complète et fi able de l’apparence visuelle ; puis de prédirecette description en intégrant statistiquement l’analyse d’imagede plusieurs facettes de la plante. Certaines variables architecturalespertinentes, et de nombreuses équivalentes, potentiellementintéressantes pour étudier le développement des buissonsau cours de leur cycle de vie, permettent de prédire voire d’expliquerl’élaboration des composantes visuelles d’un cultivar

Construction of the architecture and visual components of a woody ornamental bush : the rose tree

Les buissons ligneux forment un modèle végétal clé pour répondreaux préoccupations sociales et environnementales.Usuellement transposé sur le modèle arborescent, leur développementarchitectural reste encore peu compris et peu étudiéau regard de leur qualité visuelle. Pour cerner et anticiper cesattentes, une méthodologie pluridisciplinaire visant le managementde la qualité visuelle des plantes d’ornement est proposée.Elle intègre l’architecture des plantes avec sa plasticité phénotypiqueet la perception de leur apparence visuelle. Sur un rosierbuisson : Rosa hybrida L. ‘Radrazz’, l’étude montre commentl’analyse architecturale avec ses outils de modélisation, l’analysesensorielle et d’image peuvent former un cadre scientifi quecohérent visant cet objectif, et transposable à d’autres taxons.Sur rosiers virtuels, et réels exposés à un gradient lumineux, l’apparencevisuelle peut être caractérisée objectivement au moyend’épreuves sensorielles sur vidéode plante en rotation à différentsstades. La vidéo permet aux sujets une meilleure représentationmentale de la plante en 3D, et ainsi une descriptionplus complète et fi able de l’apparence visuelle ; puis de prédirecette description en intégrant statistiquement l’analyse d’imagede plusieurs facettes de la plante. Certaines variables architecturalespertinentes, et de nombreuses équivalentes, potentiellementintéressantes pour étudier le développement des buissonsau cours de leur cycle de vie, permettent de prédire voire d’expliquerl’élaboration des composantes visuelles d’un cultivar.Shrubs form a key plant model to meet social and environmentalconcerns. Usually transposed on the tree model, their architecturaldevelopment is still ill-known and understudied to address visualquality. To identify and anticipate such expectations, the visual qualitymanagement of ornamental plants through a multidisciplinarymethodology is proposed. It includes architecture of the plants withits phenotypic plasticity and their visual appearance perception.On a rose bush: Rosa hybrida L. ‘Radrazz’, this work shows howarchitectural analysis with its modeling tools, sensory evaluationand image analysis can form a coherent scientifi c framework toface up to such a purpose, and be transposed for other taxa. Onvirtual rose bushes, and real ones exposed to a light gradient, thevisual appearance can be characterized objectively by means ofsensory tests using rotating plant video at different stages.Thevideo stand enables a better mental representation of the plant 3Dby the subjects, leading to a more complete and reliable descriptionof the plant visual appearance; then to predict this descriptionthrough statistically integrated image analysis of multiple plantfacets. Some relevant architectural variables, with numerousequivalents, potentially interesting to study the architecturaldevelopment of bushes during their life cycle, enabled to predicteven explain how visual components were built for a cultivar. Fora better market responsiveness, this work lays the foundationfor drafting interactive decision and innovation support tools for

The Challenge: grouping and characterizing fourty virtual rose bushes presented in videos. Use of perceptive free sorting and verbalization.

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Shape descriptors to characterize the shoot of entire plant from multiple side views of a motorized depth sensor

International audienceA low-cost depth camera recently introduced is synchronized with a specially devised low-cost motorized turntable. This results in a low-cost motorized depth sensor, able to provide a large number of registered side views, which is exploited here for the quantitative characterization of the shoots of entire plants. A set of four new shape descriptors of the shoots, constructed from the depth images on multiple side views of the shoots of plants, is proposed. The four descriptors quantify effective volume, multiscale organization, spatial symmetries and lacunarity of the plants. The four descriptors are here defined, validated on synthetic scenes with known properties, and then applied on nine different-looking real plants to illustrate their abilities for quantitative characterization and comparison. The resulting motorized depth sensor and associated image processing open new perspectives to various plant science applications including plant growth and architecture monitoring, plant response to stresses or the assessment of aesthetic parameters for ornamental plants

Predicting sensorial attribute scores of ornamental plants assessed in 3D through rotation on video by image analysis: A study on the morphology of virtual rose bushes

International audienceThe visual appearance of a plant is tightly linked to its 3D architecture, and can be characterized by means of sensorial experiments. Providing a method to manage image features to predict objective visual traits of real or in silico ornamental plants seen and assessed in rotation, could be a valuable tool to take into account the 3D of the plants in order to reach faster, more faithful and more reproducible hedonic-free characterizations. The present study aims to present a simple approach to manage image data from rotating plant videos in order to predict some visual characteristics as beforehand determined through a non-hedonic sensory evaluation. It is proposed to implement plant morphometrical descriptors using common descriptive statistics computed from 2D features measured along the plant rotation with the aim to integrate the plant 3D. As a preliminary study to evaluate the potential of the proposed approach, the present experiment used virtual plants. First, a sensory profile on 20 virtual rose bushes videos for which 12 plant morphology-related sensory attributes were developed is presented. In parallel, 2D features from the video frames have been extracted considering an 8°-rotation interval and their discriminant power have been checked. Results showed that each sensory attributes presented at least one strong and significant linear relationship with a specific morphometrical descriptor (Pearson’s correlation coefficient ⩾0.8, p-values < 0.001). A stepwise predictor selection procedure to design ordinary least squares (OLS) regression models allowed quite good modeling of the sensory attributes with no more than four morphometrical descriptors (adjusted R2 ⩾ 0.9). Regression on components and penalized models presented also good to acceptable fit, but model cross-validation (CV) and model complexity confirmed the relevance of the OLS models and their selected morphometrical descriptors (R2-CV ⩾ 0.9 and root mean square error of prediction <0.7) and strengthened the pertinence of transposing this image data management for experiments with real plants considering also their color characteristics thus achieving a proof of the concept

A new approach to predict the visual appearance of rose bush from image analysis of 3D videos

International audienceSensory methods applied to ornamental plants enable studying more objectively plant visual qualitykey drivers of consumer preferences. However, management upkeep of a trained panel for sensory profile is time-consuming, not flexible and represents non-negligible costs. The present paper achieves the proof of the concept about using morphometrical descriptors upkeep of a trained panel for sensory profile is time-consuming, not flexible and represents non-negligible costs. The present paper achieves the proof of the concept about using morphometrical descriptors integrating 2D image features from rotating virtual rose bush videos to predict their visual appearance according to different sensory attributes. Using real plants cultivated under a shading gradient and imaged in rotation during three development stages, acceptable prediction error of the sensory attributes ranging from 6.2 to 19.8% (normalized RMSEP) were obtained with simple ordinary least squares OLS) regression models and linearization. The most accurate model obtained was for the flower quantity perception.Finally, a secondary analysis highlighted in most of the studied traits a significant influence of defoliation, stressing herefore the impact of the leaves on plant architecture, and thus on the visual appearance

Analyse sensorielle en horticulture ornementale

International audienceAesthetic quality is an important criterion for assessing ornamental plants, and needs objective measurements. In previous works, we have adapted the tools of sensory analysis to the measurement of the visual quality of the rosebush. Some applications allowed the validation of this method. However, its implementation is expensive. In order to reduce this cost, focusing on floribundity, we compared the sensory methods to other more conventional methods: morphometric measurements, and the methodology used by the Union for the Protection of New Varieties of Plants (UPOV). Rosebushes from four varieties, used by UPOV as reference varieties to scale the number of flowers, were grown in Angers from 2009 to 2011. They were assessed, using the three methodologies. The results, highlighting a strong correlation between these methods, are discussed.La qualité esthétique est un important critère d'évaluation des plantes ornementales, et doit être mesurée objectivement. Dans de précédents travaux, nous avons adapté les outils de l'analyse sensorielle à l'évaluation de la qualité visuelle du rosier buisson. Des applications ont permis de valider cette méthode. Cependant, sa mise en oeuvre est coûteuse. Afin de réduire ce coût, nous avons comparé, en nous focalisant sur la floribondité, la méthodologie sensorielle à d'autres méthodes plus classiques : l'analyse morphométrique d'une part et la méthodologie utilisée par l'Union pour la Protection des Obtentions Végétales (UPOV), d'autre part. Des rosiers de quatre variétés utilisées par l'UPOV comme variétés de référence pour l'échelle de la quantité de fleurs, ont été cultivés à Angers de 2009 à 2011. Ils ont été évalués au moyen des trois méthodologies. Les résultats montrant de fortes corrélations entre les scores obtenus sont discutés

Ornamental plants architectural characteristics in relation to visual sensory attributes: a new approach on the rose bush for objective evaluation of the visual quality

International audienceWithin ornamental horticulture context, visual quality of plants is a critical criterion for consumers looking for immediate decorative effect products. Studying links between architecture and its phenotypic plasticity in response to growing conditions and the resulting plant visual appearance represents an interesting lever to propose a new approach for managing product quality from specialized crops. Objectives of the present study were to determine whether architectural components may be identified across different growing conditions (1) to study the architectural development of a shrub over time; and (2) to predict sensory attributes data characterizing multiple visual traits of the plants. The approach addressed in this study stands on the sensory profile method using a recurrent blooming modern rose bush (Rosa hybrida ‘Radrazz’) presented in rotation using video stimuli. Plants were cultivated under a shading gradient in three distinct environments (natural conditions, under 55 and 75% shading net). Architecture and video of the plants were recorded during three stages, from 5 to 15 months after plant multiplication. Except for visual traits at the scale of the organs, panel performance was highly satisfying for most of the sensory attributes listed. Strong correlations (Spearman’s coefficient ranging from 0.72 to 0.98) were found between them and architectural variables extracted from phytomer to plant scale data. Acceptable to very satisfying models were obtained (Q2 ranged from 0.49 to 0.95, normalized RMSEP <17.3%) with simple ordinary least squares regression and variable transformation to encompass non-linear relationships. The proposed approach presents therefore a powerful way to gain a better insight into the architecture of shrub plants together with their visual appearance to target processes of interest in order to optimize growing conditions or select the most fitting genotypes across breeding programs, with respect to contrasted consumer preferences

Assessment of the rose bush floribundity and architecture

International audienceFloribundity defined as “the capacity of a plant to produce abundant flowers at high density on each of its branches”, is a key element of the aesthetic quality of the ornamental plants. In the case of many species, including the rosebush, this feature is strongly related to the plant architecture which is determined by the genotype, the environment and the crop management. To address these questions, the Architecture and Environment (ARCH-E) team of the Research Institute on Horticulture and Seeds (http://www6.angers-nantes.inra.fr/irhs) in collaboration with the Genetic determinism & Diversity of Ornamental plants (GDO) team of the same institute, is developing an integrative research program whereby environmental effects on the establishment of the plant architecture are examined from the molecular to the whole plant levels using plant sciences (physiology, genetics, molecular biology, biochemistry…), sensory analysis and modelling studies. The aim of the poster is to present a review of the studies (listed below) managed by the team, focusing on methods to assess and compare the floribundity of some rose cultivars, considered as example varieties by the International Union for the Protection of New Varieties of Plants (UPOV)