31 research outputs found
Controlling for genetic identity of varieties, pollen contamination and stigma receptivity is essential to characterize the self-incompatibility system of Olea europaea L.
open7siBervillé et al. express concern about the existence of the diallelic self-incompatibility (DSI) system in Olea europaea, mainly because our model does not account for results from previous studies from their group that claimed to have documented asymmetry of the incompatibility response in reciprocal crosses. In this answer to their comment, we present original results based on reciprocal stigma tests that contradict conclusions from these studies. We show that, in our hands, not a single case of asymmetry was confirmed, endorsing that symmetry of incompatibility reactions seems to be the rule in Olive. We discuss three important aspects that were not taken into account in the studies cited in their comments and that can explain the discrepancy: (i) the vast uncertainty around the actual genetic identity of vernacular varieties, (ii) the risk of massive contamination associated with the pollination protocols that they used and (iii) the importance of checking for stigma receptivity in controlled crosses. These studies were thus poorly genetically controlled, and we stand by our original conclusion that Olive tree exhibits DSI.openSaumitou-Laprade, Pierre; Vernet, Philippe; Vekemans, Xavier; Castric, Vincent; Barcaccia, Gianni; Khadari, Bouchaib; Baldoni, LucianaSaumitou-Laprade, Pierre; Vernet, Philippe; Vekemans, Xavier; Castric, Vincent; Barcaccia, Gianni; Khadari, Bouchaib; Baldoni, Lucian
A Paradigm Shift, or a Paradigm Adjustment? The Evolution of the Oleaceae Mating System as a Small-Scale Kuhnian Case Study
Kuhn (1962) proposed an evolutionary model to explain how scientific knowledge is built, based on the concept of paradigm. Even though Kuhn’s model is general, it has been applied to only a few topics in evolutionary biology, almost exclusively to broad-based paradigms. We analyze here, through the lens of Kuhn’s theory, a small-scale paradigm change that occurred with the resolution of the controversy about the mating system of a Mediterranean shrub Phillyrea angustifolia (Oleaceae). We first summarize the different steps of the paradigm change and replace them in the more general context of sex ratio theory. Second, we show how the different steps of the paradigm change can be interpreted by Kuhnian concepts and tools. Finally, we discuss the actual and future status of the new paradigm
Roombots-Towards Decentralized Reconfiguration with Self-Reconfiguring Modular Robotic Metamodules
This paper presents our work towards a decentralized reconfiguration strategy for self-reconfiguring modular robots, assembling furniture-like structures from Roombots metamodules. We explore how reconfiguration by locomotion from a configuration A to a configuration B can be controlled in a distributed fashion. This is done using Roombots metamodules—two Roombots modules connected serially—that use broadcast signals, lookup tables of their movement space, assumptions about their neighborhood, and connections to a structured surface to collectively build desired structures without the need of a centralized planne
Aligning Value and Implementation in Service Design: A Systemic Approach
The promise of service design is to enable a service supplier to prosper by delivering continuous value to customers. This prosperity is of strategic value to the service supplier. There is value in a service for both the service supplier and its service customers. We call these two values, service supplier value and service adopter value. When designing a service it is necessary to align both value propositions with the service components and service features. To this end, we propose to use a systemic method where whole (i.e. black box) and composite (i.e. white box) reasoning are interleaved on both the organizational and functional dimensions. We begin by producing an as-is model that describes how the value is created for the customer and how it is captured by the service supplier. Service improvement opportunities are identified in terms of value to both service adopter and service supplier. A to-be model is built that specifies the new interaction between actors and their new responsibilities and thereby, new service components and features. The method is illustrated with an example based on the service offering and implementation of Amazon.com in Amazon Marketplace
Systemic Service Design: Aligning Value and Implementation
Abstract. The promise of service orientation is that it enables an organization to prosper by delivering continuous value to customers. This prosperity is of strategic value to the organization. There is value in service orientation for both the organization and its customers. We call these two values, customer value and strategic value. When designing a service it is necessary to align both value propositions with the service building blocks. We propose to use a systemic method where whole and composite reasoning are interleaved on both the organizational and functional dimensions. We begin by producing an as-is model that describes how customer value is delivered by a set of actors and the responsibility of each actor. Improvement opportunities are identified in terms of customer value and strategic value to the organization. A to-be model is built that specifies the new interaction between actors and their new responsibilities. The method is illustrated with an example.
The joint evolution and maintenance of self-incompatibility with gynodioecy or androdioecy
International audienc
Genetic mapping of sex and self-incompatibility determinants in the androdioecious plant Phillyrea angustifolia
A bstract The diversity of mating and sexual systems in angiosperms is spectacular, but the factors driving their evolution remain poorly understood. In plants of the Oleaceae family, an unusual self-incompatibility (SI) system has been discovered recently, whereby only two distinct homomorphic SI specificities segregate stably. To understand the role of this peculiar SI system in preventing or promoting the diversity of sexual phenotypes observed across the family, an essential first step is to characterize the genetic architecture of these two traits. Here, we developed a high-density genetic map of the androdioecious shrub P. angustifolia based on a F1 cross between a hermaphrodite and a male parent with distinct SI genotypes. Using a double restriction-site associated digestion (ddRAD) sequencing approach, we obtained reliable genotypes for 196 offspring and their two parents at 10,388 markers. The resulting map comprises 23 linkage groups totaling 1,855.13 cM on the sex-averaged map. We found strong signals of association for the sex and SI phenotypes, that were each associated with a unique set of markers on linkage group 12 and 18 respectively, demonstrating inheritance of these traits as single, independent, mendelian factors. The P. angustifolia linkage map shows robust synteny to the olive tree genome overall. Two of the six markers strictly associated with SI in P. angustifolia have strong similarity with a recently identified 741kb chromosomal region fully linked to the SI phenotype on chromosome 18 of the olive tree genome, providing strong cross-validation support. The SI locus stands out as being markedly rearranged, while the sex locus has remained relatively more collinear between the two species. This P. angustifolia linkage map will be a useful resource to investigate the various ways by which the sex and SI determination systems have co-evolved in the broader phylogenetic context of the Oleaceae family
Evidence for the long-term maintenance of a rare self-incompatibility system in Oleaceae
International audienc
Cartographie génétique des déterminants du sexe et de l'auto-incompatibilité chez la plante androdioïque Phillyrea angustifolia
International audienceThe diversity of mating and sexual systems in angiosperms is spectacular, but the factors driving their evolution remain poorly understood. In plants of the Oleaceae family, an unusual self-incompatibility (SI) system has been discovered recently, whereby only two distinct homomorphic SI specificities segregate stably. To understand the role of this peculiar SI system in preventing or promoting the diversity of sexual phenotypes observed across the family, an essential first step is to characterize the genetic architecture of these two traits. Here, we developed a high-density genetic map of the androdioecious shrub P. angustifolia based on a F1 cross between a hermaphrodite and a male parent with distinct SI genotypes. Using a double restriction-site associated digestion (ddRAD) sequencing approach, we obtained reliable genotypes for 196 offspring and their two parents at 10,388 markers. The resulting map comprises 23 linkage groups totaling 1,855.13 cM on the sexaveraged map. We found strong signals of association for the sex and SI phenotypes, that were each associated with a unique set of markers on linkage group 12 and 18 respectively, demonstrating inheritance of these traits as single, independent, mendelian factors. The P. angustifolia linkage map shows robust synteny to the olive tree genome overall. Two of the six markers strictly associated with SI in P. angustifolia have strong similarity with a recently identified 741kb chromosomal region fully linked to the SI phenotype on chromosome 18 of the olive tree genome, providing strong cross-validation support. The SI locus stands out as being markedly rearranged, while the sex locus has remained relatively more collinear between the two species. This P. angustifolia linkage map will be a useful resource to investigate the various ways by which the sex and SI determination systems have co-evolved in the broader phylogenetic context of the Oleaceae family.La diversité des systèmes de reproduction et des types sexuels chez les angiospermes est spectaculaire, mais les facteurs de leur évolution restent mal compris. Chez les plantes de la famille des Oleacées, un système d'auto-incompatibilité (SI) inhabituel a été découvert récemment, dans lequel seules deux spécificités SI distinctes mais parfaitement homomorphes ségrégent de manière stable. Pour comprendre le rôle de ce système SI particulier dans la prévention ou la promotion de la diversité des phénotypes sexuels observés dans la famille des Oléacées, une première étape essentielle est de caractériser l'architecture génétique de ces deux traits. Ici, nous avons développé une carte génétique à haute densité de l'arbuste androdioïque P. angustifolia basée sur un croisement F1 entre un hermaphrodite et un parent mâle avec des génotypes SI distincts. En utilisant une approche de séquençage par double digestion associée à un site de restriction (ddRAD), nous avons obtenu des génotypes fiables pour 196 descendants et leurs deux parents sur 10 388 marqueurs. La carte résultante comprend 23 groupes de liaison totalisant 1 855,13 cM sur la carte moyenne par sexe. Nous avons trouvé de forts signaux d'association pour les phénotypes sexe et SI, qui étaient chacun associés à un ensemble unique de marqueurs sur les groupes de liaison 12 et 18 respectivement, démontrant l'héritage de ces traits comme facteurs mendéliens uniques et indépendants. La carte de liaison de P. angustifolia montre une synténie robuste avec le génome de l'olivier dans son ensemble. Deux des six marqueurs strictement associés au SI chez P. angustifolia présentent une forte similitude avec une région chromosomique de 741 kb récemment identifiée et entièrement liée au phénotype SI sur le chromosome 18 du génome de l'olivier, ce qui fournit une forte validation croisée. Le locus SI se distingue par un réarrangement marqué, tandis que le locus sexuel est resté relativement colinéaire entre les deux espèces. Cette carte de liaison de P. angustifolia sera une ressource utile pour étudier les différentes façons dont les systèmes de détermination du sexe et du SI ont co-évolué dans le contexte phylogénétique plus large de la famille des Oléacées
Selfish male-determining element favors the transition from hermaphroditism to androdioecy
International audienc