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24, chemin de Borde Rouge -Auzeville - CS52627 31326 Castanet Tolosan cedex - France

Last update: May 2021

Menu Logo Principal Plant pathology unit - INRA AVIGNON

Pathologie vegetale

Zone de texte éditable et éditée et rééditée

Etiology - Epidemiology

Epidemiology of the gray mold caused by Botrytis cinerea

Spores of Botrytis cinerea

Spores of Botrytis cinerea

© Pathologie végétale INRAE - Avignon

The MISTRAL team has been exploring a more comprehensive perspective on the ecology and biology of Botrytis cinerea concerning the habitats and environmental factors that mold the behavior and influence the diversification of these pathogens and that could lead to more efficient strategies of disease management.

Botrytis cinerea  is a fungus causing gray mold on more than 220 host plants, including high-value crops and wild species. B. cinerea populations may evolve according to time, space, host and anthropic activities but that evolution patterns still need to be understood in crop production conditions specific to France. Genetic structure of the populations was investigated using microsatellite markers.

Host specificity in Botrytis cinerea

B. cinerea has long been considered non-host specific. However, recent studies have revealed genetic differentiation between strains of B. cinerea isolated from different host plants.

Characterisation of Botrytis cinerea populations: host specialization

Experimental design with lettuce and tomato plants

© Pathologie végétale INRAE - Avignon

  • host specialization of Botrytis cinerea: differences observed between populations isolated from diverse agro-systems (tomato, lettuce, grapevine) or wild plant (bramble)
  • genetic differentiation of populations over successive rotations tomato-lettuce in greenhouses
  • flow of Botrytis cinerea inoculum between lettuce crop and soil
  • Leyronas, C., Bryone, F., Duffaud, M., Troulet, C., Nicot, P. 2015. Assessing host specialization of Botrytis cinerea on lettuce and tomato by genotypic and phenotypic characterization. Plant Pathology, 64, 119-127.
  • Leyronas, C., Duffaud, M., Pares, L., Jeannequin, B., Nicot, P. C. 2015. Flow of Botrytis cinerea inoculum between lettuce crop and soil. Plant Pathology, 64, 701-708.
  • Mercier, A., Simon, A., Lapalu, N., Giraud, T., Bardin, M., Walker, A.-S., Viaud, M., Gladieux, P., 2020. Population genomics reveals molecular determinants of specialization to tomato in the polyphagous fungal pathogen Botrytis cinerea. bioRxiv: 35 p. DOI : 10.1101/2020.07.24.219691
  • Walker, A. S., Gladieux, P., Decognet, V., Fermaud, M., Confais, J., Roudet, J., Bardin, M., Bout, A., Nicot, P. C., Poncet, C., Fournier, E. 2015. Population structure and temporal maintenance of the multihost fungal pathogen Botrytis cinerea: causes and implications for disease management. Environmental Microbiology, 17, 1261-1274.

Geographic structuration of the populations at different scales

Our results on this topic concern B. cinerea in tomato glasshouses. The genetic diffrentiation of the populations was investigated at the local scale (same glasshouse during several years), regional (different glasshouses in PACA area) and national glasshouses (french or algerian areas).

Symptoms of Botrytis cinerea in tomato glasshouses

Symptoms of Botrytis cinerea in tomato glasshouses

© Pathologie végétale INRAE - Avignon

  • establishment of clonal lineages of B. cinerea during a growing season due to dissemination of spores from diseased plants
  • high level of clonality due to the predominance of some particular haplotypes: striking contrast which was observed in other agrosystems, in particular in grapevine
  • geographic structuration: main clonal lineages differed in the glasshouses sampled
  • Adjebli, A., Leyronas, C., Aissat, K., Nicot, P. 2015. Comparison of Botrytis cinerea populations collected from tomato greenhouses in Northern Algeria. Journal of Phytopathology, 163, 124-132.
  • Bardin, M., Decognet, V., Nicot, P. 2014. Remarkable predominance of a small number of genotypes in greenhouse populations of Botrytis cinerea. Phytopathology, 104, 859-864.
  • Decognet, V., Bardin, M., Trottin-Caudal, T., Nicot, P. 2009. Rapid change in the genetic diversity of Botrytis cinerea populations after the introduction of strains in a tomato glasshouse. Phytopathology 99, 185-193.