Modélisation des effets des systèmes de culture sur la dynamique de l’orobanche rameuse en interaction avec les adventices

Branched broomrape, Phelipanche ramosa (L.) Pomel, is a parasitic plant which causes important yield losses in crops, particularly in winter oilseed rape in France. In order to design efficient pest management strategies, we modelled the effects of cropping systems on branched broomrape dynamics in interaction with weeds and crops in a model called PHERASYS. PHERASYS functions and parameters were based on literature and on our own experiments. The model simulates the complete life-cycle of the parasite, from seed dynamics in the soil to seed production after development on the host. Interactions between the parasite and crops and weeds were characterized at the species level and at the plan…

Les semences de la plante parasite orobanche rameuse ont une dormance saisonnière qui varie au niveau intraspécifique et une faible mortalité au champ

L’orobanche rameuse (Phelipanche ramosa) est une plante parasite bioagresseur majeur du colza en France. Les connaissances sur la viabilité et la dormance de ses semences dans le sol sont cruciales pour contrôler l’orobanche mais restent à acquérir. La présente étude vise à quantifier ces processus grâce à une expérience d’enfouissement de semences au champ de deux ans. Deux populations génétiquement distinctes ont été étudiées, collectées sur colza d’hiver et chanvre respectivement. La mortalité des semences est très faible pour les deux populations (4-7% par an). Les semences montrent une dormance saisonnière dont le timing et l’amplitude varient en fonction de la population, avec une dor…

Désherbage : changement climatique, quel avenir pour les mauvaises herbes ?

National audience; Le réchauffement climatique a un certain nombre d’effets sur le fonctionnement de l’agriculture. En matière de désherbage, des travaux sont en cours pour évaluer les risques d’évolution des espèces adventices. Les caractéristiques biologiques de certaines espèces les prédisposent à devenir des problèmes majeurs.

Weed-DATA Base de données ‘Traits’ des plantes adventices des agroécosystèmes

SPEEAECOLDURGEAPSIéquipe CAPA; absent

Broomrape weeds. Underground mechanisms of parasitism and associated strategies for their control: a review

prod 2018-285d SPE GESTAD Agrosup INRA CT?; International audience; Broomrapes are plant-parasitic weeds which constitute one of the most difficult-to-control of all biotic constraints that affect crops in Mediterranean, central and eastern Europe, and Asia. Due to their physical and metabolic overlap with the crop, their underground parasitism, their achlorophyllous nature, and hardly destructible seed bank, broomrape weeds are usually not controlled by management strategies designed for non-parasitic weeds. Instead, broomrape are in a current state of intensification and spread due to lack of broomrape-specific control programs, unconscious introduction to new areas and may be decline of …

Complexity of the tripartite interaction in the rhizosphere: case of soil-borne pathogenic fungi with the holoparasitic plant Phelipanche ramosa and its host plant

PheraSys – un projet de modélisation de la dynamique de l'orobanche dans les systèmes de culture

National audience; La gestion de la plante parasite Phelipanche ramosa (L.) Pomel (orobanche) est surtout basée sur des méthodes préventives, notamment le travail du sol et la rotation. Ce parasite peut infecter les racines d'une large gamme d'espèces cultivées mais aussi d'adventices non-parasites. L'objectif de notre projet est de développer un modèle, appelé PHERASYS, quantifiant les effets de système de culture sur la dynamique du parasite, en interaction avec la flore adventice non-parasite, et de le coupler avec le modèle existant FLORSYS qui prédit la flore adventice dans les systèmes de culture. Nous avons déjà développé une version préliminaire à partir de la littérature que nous a…

How to pit weeds against parasitic plants. A simulation study with Phelipanche ramosa in arable cropping systems

Biocontrol of the parasitic plant species Phelipanche ramosa, using rapeseed rhizosphere fungi or phytotoxic metabolites

International audience

Trophic relationships between the parasitic plant species phelipanche ramosa (L.) and different hosts depending on host phenological stage and host growth rate

Prod 2018-285c INRA AGROSUP GESTAD SPE CT3 SPE CT1 EJ2 EA; International audience; Phelipanche ramosa (L.) Pomel (branched broomrape) is a holoparasitic plant that reproduces on crops and also on weeds, which contributes to increase the parasite seed bank in fields. This parasite extracts all its nutrients at the host’s expense so that host–parasite trophic relationships are crucial to determine host and parasite growth. This study quantified the intensity with which P. ramosa draws assimilates from its host and analyzed whether it varied with host species, host phenological stage and host growth rate. A greenhouse experiment was conducted on three host species: the crop species Brassica na…

Modélisation des effets des systèmes de culture sur la dynamique de la plante parasite orobanche rameuse en interaction avec la flore adventice

National audience

Variabilité génétique, d’histoire de vie et d’infection des populations de l’orobanche rameuse en France

L'orobanche rameuse est une Angiosperme holoparasite épirhize qui infecte une large gamme de cultures annuelles. Selon la culture hôte, la durée de son cycle peut varier de 14 semaines (sur tomate/tabac) à 40 semaines (sur colza). Nous avons mené une expérimentation d'infections croisées afin d'évaluer l'intensité et la cinétique d''infection de populations d'orobanche. Deux populations du parasite, P-long collectée sur le colza et P-short collectée sur le tabac, ont été cultivées sur deux cultures (colza et tomate). Après, 4, 8, 12 et 16 semaines de culture, l'intensité d'infection et la distribution des stades de développement de l'orobanche ont été déterminées. Les deux populations d'oro…

Infestation de Rhamphicarpa fistulosa (Hoschst.) Benth. en riziculture de bas-fonds au nord du Togo

International audience; Le riz constitue de nos jours la base alimentaire de plus de 2,5 milliards de personnes en Afrique subsaharienne où sa demande ne cesse de croître. Pour faire face à cette demande qui dépasse souvent doublement les productions nationales, et pour diminuer ses importations sans cesse croissantes, le Togo à l’instar des pays ouest-Africains a élaboré un document stratégique qui mise sur l’extension et la productivité des rizières de bas-fond. Malheureusement, les bas-fonds rizicoles en Afrique tropicale sont souvent confrontés à la pression des adventices et plus particulièrement des adventices parasites de la famille des Orobanchaceae. Rhamphicarpa fistulosa, plante h…

A preliminary approach for modelling the effects of cropping systems on the dynamics of broomrape ( Phelipanche ramosa) in interaction with the non-parasitic weed flora

International audience; The current decrease in herbicide use may increase and diversify weed flora in crops as well as companion bioagressors spreading via weeds. Among these bioagressors is Phelipanche ramosa (L.) Pomel, a parastic plant which is very harmful on oilseed rape. The objective of the present work was to develop a new model (called PheraSys) of the effects of cropping systems on parasite dynamics, in interaction with non-parasitic weed hosts. The structure of this first model version was based on models developed for other parasitic plants and on FlorSys which quantifies the effects of cropping systems on non-parasitic weed flora. PheraSys was parametrized with preliminary val…

[Site Web photos orobanche rameuse]

Modelling the effects of cropping systems on the dynamics of a parasitic weed, Phelipanche ramosa, in interaction with the non-parasitic weed flora

International audience; The current decrease in herbicide use may increase and diversify weed flora in crops as well as companion bioagressors spreading via weeds. Among these bioagressors is Phelipanche ramosa, a parastic plant which is very harmful on oilseed rape. The objective of the present work was to develop a model (called PHERASYS) of the effects of cropping systems on parasite dynamics, in interaction with non-parasitic weed hosts. The structure of the first model version was based on models developed for other parasitic plants and on FLORSYS which quantifies the effects of cropping systems on non-parasitic weed flora. PHERASYS was parametrized with preliminary values from literat…

Plantes-microorganismes, orobanche

Étude de l'infection de la plante parasite Rhamphicarpa fistulosa en riziculture au Togo

Rhamphicarpa fistulosa (Hochst.) Benth. is an annual facultative root-parasitic weed found in lowlands and floodplains in tropical Africa. It has been reported as the major constraint to rice cultivation in the savannah region of Togo. A survey was conducted in 2012 to access its distribution and to collect information on farmers’ knowledge of its control. Rhamphicarpa fistulosa was found in 80% of the 33 visited lowlands. The period of abundance is in August-September when the highest infection (90%) was found on sandy and clay soils. When the parasite was present, 94 other weeds belonging to 24 botanical families were recorded. As management method, farmers use weeding and chemical fertil…

Gestion des plantes adventices parasites

Prod 2018-236m GESTAD AGROSUP POLE SPE EA

Biocontrol of Phelipanche ramosa, a parasitic weed of rapeseed in France, using soil-borne fungi

National audience; Phelipanche ramosa is a major holoparasitic weed, which became a major agronomic problemfor rapeseed crops in France. Weed control in rapeseed does not have a direct impact on thisparasitic weed whose half of the reproductive cycle occurs on the root system of its host. Since1990, broomrape expanded its distribution area starting from the Poitou-Charentes region.Necrosis symptoms on broomrapes from this region should be indicators of potentialpathogenic fungi. Furthermore, these pathogenic fungi should be able to infest differentbroomrape stages. The aim of my thesis is to contribute to the evaluation of an integrated controlsolution for this parasitic weed and focus on t…

Biocontrol of the parasitic plant species Phelipanche ramosa, using rapeseed rhizosphere fungi or phytotoxic metabolites they produce.

Phelipanche ramosa (L.) Pomel, branched broomrape, is a major root-holoparasitic damaging weed with a large host range besides a strong adaptation to rapeseed. Broomrape seed germination is necessarily triggered by host root exudates. This ensures that they germinate close to a host root where they attach and establish a vascular connection to take up water and nutrients. No efficient broomrape management technique has been validated yet. Biocontrol could be an alternative but there is currently no biological control agent on the market. Indeed tripartite interactions between the host plant, the parasitic plant and a pathogenic agent of the latter are complex and poorly understood. The obje…

Biocontrol against the root parasitic plant species Phelipanche ramosa, branched broomrape of tobacco

The branched orobanche, Phelipanche ramosa L., is an obligate parasitic weed that has become, in France, a major agronomic problem in tobacco crops; yield and quality losses can be total and cause growers to reduce the producing area due to lack of available healthy plots or to abandon the crop. Because chemical management is not effective, biocontrol is certainly the alternative to propose but there is currently no biological control agent on the market to meet the expectations of producers and control this parasitic plant. Only a few microorganisms or molecules, are presented as potential and promising candidates in conclusion of scientific articles but the finalization is absent. A colle…

Weed community of lowland rice system in northern Togo's Savannah region

International audience; Weeds are the major biotic constraint for lowland rice production systems in Togo, particularly in the Savannah region where rice cultivation follows traditional practices with very little mechanization or synthetic pesticide treatment. In order to identify and categorize weed flora of this agricultural system, vegetation surveys were conducted in Northern Togo’s lowlands during the growing seasons of 2012 and 2013. Full floristic surveys were conducted in 33 lowland sites, selected for their accessibility and importance in terms of rice production. A total of 97 weed species from 26 plant families were recorded in 2012 against 103 weed species in 28 families in 2013…

La filière crème de cassis en Bourgogne

Burgundy became the cradle of blackcurrant liqueur production at the end of the nineteenth century, and today, growing and processing the berries remains a significant economic activity for the region. The value chain is well-structured, but the domestic market is mature, forcing operators to come up with new strategies both at the level of each enterprise and collectively. Efforts to position blackcurrant liqueur as a trendy, contemporary drink have faced a struggle to win over domestic consumers, but the same can be said of all products in the segment. In contrast, foreign consumers are creating new ways to use the blackcurrant liqueur, opening up promising export opportunities for the Fr…

L'orobanche rameuse. Une plante parasite dont la variabilité s'avère complexe

EASPEEcolDurGEAPSICT1; National audience; L'orobanche rameuse (Phelipanche ramosa (L.) Pomel) est une plante connue pour parasiter préférentiellement la tomate dans les pays du bassin méditerra-néen, le tabac et le chanvre en Europe centrale. Mais le colza semble être un nouvel hôte préférentiel avec une augmentation du nombre de parcelles infectées en Bulgarie, Espagne, France et Italie. Pourquoi cette orobanche inquiète Une expansion massive sur colza En France, on observe une expansion massive de cette espèce dans les parcelles de colza depuis la fin des années 1990.

Etude de l’infection la plante parasite Rhamphicarpa fistulosa en riziculture au Togo

Rhamphicarpa fistulosa (Hochst.) Benth. is an annual facultative root-parasitic weed found in lowlands and floodplains in tropical Africa. It has been reported as the major constraint to rice cultivation in the savannah region of Togo. A survey was conducted in 2012 to access its distribution and to collect information on farmers' knowledge of its control. Rhamphicarpa fistulosa was found in 80% of the 33 visited lowlands. The period of abundance is in August-September when the highest infection (90%) was found on sandy and clay soils. When the parasite was present, 94 other weeds belonging to 24 botanical families were recorded. As management method, farmers use weeding and chemical fertil…

Modélisation des effets des systèmes de culture sur la dynamique de l’orobanche rameuse (Phelipanche ramosa (L.) en interaction avec les adventices

EASPEGESTADAGROSUPINRA; L’orobanche rameuse, Phelipanche ramosa (L.) Pomel, est une plante parasite qui cause d’importantes pertes de rendements dans les cultures, particulièrement en colza en France. Afin de concevoir des stratégies de gestion efficaces du parasite, nous avons modélisé les effets des systèmes de culture sur la dynamique de l’orobanche rameuse en interaction avec les cultures et les adventices dans le modèle PheraSys. PheraSys simule le cycle de vie complet de l’orobanche rameuse, de la dynamique du stock semencier dans le sol à la fructification après développement du parasite sur son hôte.

Orobanche rameuse du tabac (Phelipanche ramosa L.) : Identifier de nouvelles solutions conventionnelles et de biocontrôle

The branching broomrape, Phelipanche ramosa L. is an obligate parasitic plant, which in a few years became a major agronomic problem for tobacco crops in France. Two approaches, aiming at controlling broomrape were tested within the framework of the ELIOT project grouping Arvalis, the CT2F cooperative and the INRA center of Dijon. The first relates to sulfonylurea herbicides, including rimsulfuron and sulfosulfuron and a systemic herbicide of the cyclohexanediones family, clethodim. The results, although instructive, do not reflect an effective control of broomrape. The second approach deals with the search for soil-borne fungi that are pathogenic to broomrape. A large number of fungal stra…

Pherasys - Un projet de modélisation de la dynamique de l’orobanche dans les systèmes de culture

La gestion de la plante parasite Phelipanche ramosa (L.) Pomel (orobanche) est surtout basée sur des méthodes préventives, notamment le travail du sol et la rotation. Ce parasite peut infecter les racines d'une large gamme d'espèces cultivées mais aussi d'adventices non-parasites. L'objectif de notre projet est de développer un modèle, appelé PHERASYS, quantifiant les effets de système de culture sur la dynamique du parasite, en interaction avec la flore adventice non-parasite, et de le coupler avec le modèle existant FLORSYS qui prédit la flore adventice dans les systèmes de culture. Nous avons déjà développé une version préliminaire à partir de la littérature que nous avons utilisée pour …

Ex ante evaluation of cropping systems for weed-mediated pests and environmental benefits with simulation–based indicators

SPEEAGESTADAGROSUP; International audience; Integrated crop protection tolerates residual weed floras if they are not harmful for crop production. These weeds can host harmful crop pests, among which parasitic plants such as broomrape (Phelipanche ramosa). They can also contribute to reduce soil erosion as well as nitrate and pesticide leaching. To evaluate these weed impacts of management practices ex ante, we developed indicators for the weed dynamics model FLORSYS (Colbach et al., 2014) and then used the model to predict weed-mediated broomrape risk and environmental benefits in cropping systems from five French regions. Materials and Methods FLORSYS is a virtual field on which cropping …

Modelling cropping system effects on branched broomrape dynamics in interaction with weeds

International audience; Branched broomrape, Phelipanche ramosa (L.) Pomel, is a parasitic plant which infects many crop and weed species. As a holoparasite, it entirely relies on host resources to survive and reproduce. It is a major pest in oilseed rape in France. Its management has to be thought as a part of the overall weed management because infected weeds either must be killed to limit crop infection or can be used to stimulate suicidal parasite germinations. In order to design efficient pest management strategies, we modelled the effects of cropping systems on P. ramosa dynamics in interaction with weeds in a model called PHERASYS. PHERASYS functions and parameters were based on the l…

Response and effect traits of arable weeds in agro-ecosystems: a review of current knowledge.

25 pages; International audience; Integrating principles of ecological intensification into weed management strategies requires an understanding of the many relationships among weeds, crops and other organisms of agro-ecosystems in a changing context. Extensively used during the last two decades in weed science, trait-based approaches have provided general insights into weed community response to agricultural practices, and recently to understanding the effect of weeds on agro-ecosystem functioning. In this review, we provide a holistic synthesis of the current knowledge on weed response and effect functional traits. Based on the literature and recent advances in weed science, we review cur…

Différences de capacités d’induction de la germination de deux pathovars d’orobanche rameuse sur une gamme d’hôtes des familles des brassicacées et fabacées

Branched broomrape (Phelipanche ramosa (L.) Pomel) is a holoparasite weed causing significant yield losses on several crops, especially in France on winter oilseed rape fields. The ability to induce germination of seeds of branched broomrape, variable between host species, represent an important information to identify the status of weed species present in the crop (host or non-host). In this study, conducted in in vitro conditions, we focused on two botanical families and two dominant pathovars of branched broomrape in France. We show that the host species is the only important explanatory factor of seed germination rate, the latter being not affected by the pathovar. Among the species stu…