CONTEXT

The MISTRAL team is composed of around 25 members, including 15 permanent staff (researchers, engineers, technicians) and a dozen non-permanent staff (interns, PhDs, post-docs, fixed-term contracts). Our research activities focus on the study of:

• phytopathogenic bacteria and fungi affecting the aerial parts of plants, in particular vegetable crops (e.g. tomato, lettuce, strawberry, garlic) and fruit crops (e.g. apricot, apple, kiwi) grown in the Mediterranean basin, as well as rapeseed.
• the interaction of these phytopathogenic agents with microbial agents (bacteriophages, bacteria and fungi) and natural biocontrol substances (e.g. plant or microbial extracts).

ORIGINALITY

Our research themes lies in the study of :

• plant pathogens passively dispersed over long distances via air and/or surface water movements (e.g. Pseudomonas syringae, Botrytis cinerea, Sclerotinia sclerotiorium, various powdery mildew agents)
• phytopathogenic and beneficial micro-organisms capable of surviving in a wide variety of substrates and contexts, including outside cultivated environments (e.g. cultivated and wild plants, surface water, snow, inert surfaces)
• plant pathogens that are (re)-emerging (Clavibacter michiganensis subsp. michiganensis - tomato, Erwinia amylovora - apple, Fusarium proliferatum - garlic) and/or that possess a broad-spectrum host range (e.g. P. syringae, B. cinerea, S. sclerotiorum).

Pathosystems studied by the MISTRAL team (from left to right):
- Botrytis cinerea on lettuce and tomato (spots on fruit and attack on stem)
- Sclerotinia sclerotiorum on lettuce
- Pseudomonas syringae on kiwi
- Clavibacter michiganensis subsp. michiganensis on tomato

OUR MISSIONS

The MISTRAL team's missions are rooted in a global, institutional, national and European objective to reduce the use of chemical pesticides in agriculture. To this end, the team generates knowledge to:

• improve epidemiosurveillance systems and schemes,
• design new, sustainable and environmentally-friendly methods for protecting plant health,
• evaluate the efficacy and sustainability of these methods,
• contribute to the adoption of new plant health management practices.

OUR OBJECTIVES

In order to pursue our missions, our research projects fall within three main objectives:

• determine the causes of plant diseases (etiology), particularly (re)emergent ones, and develop diagnostic and early detection tools
• develop and deepen our knowledge of the ecology of phytopathogenic agents and beneficial microbial agents (i.e. for biocontrol), and of the epidemiology of plant diseases. Specifically, our research projects aim to:
  • describe and characterize the phenotypic diversity and genetic structure of populations of pathogenic and beneficial microorganisms in different reservoirs, in and outside cultivated environments,
  • highlight and refine the understanding of long-distance dispersal processes via air and water mass movements,
  • study the multiple biotic and abiotic factors influencing the infectious cycle, the virulence of pathogens and the severity of the diseases they cause,
  • identify the molecular determinants of survival capacity in various environments (e.g. plants, river water), as well as virulence (e.g. on plants) and resistance (e.g. to biocontrol agents) mechanisms.
• evaluate the efficacy and sustainability of biocontrol against pests and their integration into protection strategies. Specifically, our team is developing research to:
  • decipher the modes of action of biocontrol agents (e.g. microorganisms, natural substances),
  • determine the factors modulating their protective efficacy and assess their durability,
  • assess the compatibility between different plant protection leverages and measure the effectiveness of their combined use (biocontrol, in situ early detection, nitrogen fertilization, UV-C treatment, thermotherapy, varietal resistance).