An ARIMNet project
WP coordinator: INRA-IGEPP
Other partners involved: CSIC, IAV, INRAT, CRRGC, INRAM
Objectives
- To develop molecular tools in order to study genetic variability in pathogens/parasite populations using different PCR-based markers,
- To identify the primary inoculum sources implicated in the development of epidemic,
- To study the epidemic process involved in the spatiotemporal development of legume pathogens,
- To identify architectural features of plant that will help to control disease development,
- To evaluate the impact of cultural practices and control method combinations for the management of the disease
Methodology and study materials
T5.1: Development of specific standard markers for pathogen population genetic studies: SSR markers or others markers (SNP,...) will be developped from sequences available in public databases and that will be made available in the course of the project from current international initiatives. Both these eSSR, or other markers will be used to study population genetic variations at different spatial and temporal scales (evolution of population structure during the growing season, comparison of the genetic structure in different locations of a same country, comparison of populations from different countries).
T5.2: Development of a landscape epidemiology study to identify the origin and the impact of different primary inoculums on the epidemic development of Ascochyta spp. Disease and the genetic structure of their populations. This task will particularly focus on the impact of wild legume species as potential sources of inoculums during the growing season. Based on a standard sampling procedure and the use of molecular markers, a 2 years field experiments will be developed for all the partners. This sampling will help us to define wild legume species that will act as a reservoir plant for pathogens. Controlled conditions experiments will be performed to characterize host specificity of these different strains.
T5.3: Dissection of the underlying mechanisms implicated in new control methods for disease reduction. Specific experiments will be developed in controlled conditions to determine which epidemic component is modified by the new control methods. Studies of plant (rain simulator) or roots architectures (rhizotron systems) effects on dispersal process of disease will be considered. Vertical progression of splash dispersal diseases in relation to the interference induced by non host canopy or particular on inoculum dispersal will also be investigated.
T5.4: Complementation of resistance with other methods for disease management of legume crops. Field experiments will be performed at different spatial and temporal scales to evaluate the impact of cultural practices and control method combinations towards disease. At a field scale, resistance associated with architectural plant features (aerial or root part) will be associated to evaluate their impact on spatiotemporal epidemic development. Measurement will concern the disease, microclimate, and architectural features. Selected resistant cultivars and various sowing dates would also be associated in field experiments conducted at various locations and countries to study the epidemiological effect of delayed sowing combined with available levels of resistance.
T5.5: Standard differential sets for race identification will be refined to allow systematic studies on the virulence spectrum of pathogen populations (rust, broomrape and ascochyta) in Mediterranean basin. Knowledge of the genetic structure of populations of plant pathogens is needed to aid in decision making strategies regarding implementation of effective control strategies and to ensure a durable efficiency of resistant cultivars. Knowledge on the population structure and pathogenic variation between strains collected in the different countries will help to constitute this standard differential set for future screening programs.
Deliverables
D5.1: Clarification of the genetic variation and adaptive potential of ascochyta species
D5.2: Identification of new control levers to better control disease development.
D5.3: Determine control method combinations that will decrease disease development.
D5.4: Identification of architectural features that will limit the spatiotemporal dispersal of the disease.
D5.5: Development of standard differential sets for race identification.
Other partners involved: CSIC, IAV, INRAT, CRRGC, INRAM
Objectives
- To develop molecular tools in order to study genetic variability in pathogens/parasite populations using different PCR-based markers,
- To identify the primary inoculum sources implicated in the development of epidemic,
- To study the epidemic process involved in the spatiotemporal development of legume pathogens,
- To identify architectural features of plant that will help to control disease development,
- To evaluate the impact of cultural practices and control method combinations for the management of the disease
Methodology and study materials
T5.1: Development of specific standard markers for pathogen population genetic studies: SSR markers or others markers (SNP,...) will be developped from sequences available in public databases and that will be made available in the course of the project from current international initiatives. Both these eSSR, or other markers will be used to study population genetic variations at different spatial and temporal scales (evolution of population structure during the growing season, comparison of the genetic structure in different locations of a same country, comparison of populations from different countries).
T5.2: Development of a landscape epidemiology study to identify the origin and the impact of different primary inoculums on the epidemic development of Ascochyta spp. Disease and the genetic structure of their populations. This task will particularly focus on the impact of wild legume species as potential sources of inoculums during the growing season. Based on a standard sampling procedure and the use of molecular markers, a 2 years field experiments will be developed for all the partners. This sampling will help us to define wild legume species that will act as a reservoir plant for pathogens. Controlled conditions experiments will be performed to characterize host specificity of these different strains.
T5.3: Dissection of the underlying mechanisms implicated in new control methods for disease reduction. Specific experiments will be developed in controlled conditions to determine which epidemic component is modified by the new control methods. Studies of plant (rain simulator) or roots architectures (rhizotron systems) effects on dispersal process of disease will be considered. Vertical progression of splash dispersal diseases in relation to the interference induced by non host canopy or particular on inoculum dispersal will also be investigated.
T5.4: Complementation of resistance with other methods for disease management of legume crops. Field experiments will be performed at different spatial and temporal scales to evaluate the impact of cultural practices and control method combinations towards disease. At a field scale, resistance associated with architectural plant features (aerial or root part) will be associated to evaluate their impact on spatiotemporal epidemic development. Measurement will concern the disease, microclimate, and architectural features. Selected resistant cultivars and various sowing dates would also be associated in field experiments conducted at various locations and countries to study the epidemiological effect of delayed sowing combined with available levels of resistance.
T5.5: Standard differential sets for race identification will be refined to allow systematic studies on the virulence spectrum of pathogen populations (rust, broomrape and ascochyta) in Mediterranean basin. Knowledge of the genetic structure of populations of plant pathogens is needed to aid in decision making strategies regarding implementation of effective control strategies and to ensure a durable efficiency of resistant cultivars. Knowledge on the population structure and pathogenic variation between strains collected in the different countries will help to constitute this standard differential set for future screening programs.
Deliverables
D5.1: Clarification of the genetic variation and adaptive potential of ascochyta species
D5.2: Identification of new control levers to better control disease development.
D5.3: Determine control method combinations that will decrease disease development.
D5.4: Identification of architectural features that will limit the spatiotemporal dispersal of the disease.
D5.5: Development of standard differential sets for race identification.
WP 5 - Epidemiological studies