Resilience of Colletotrichum gloeosporioides strains infecting yams to dry period and elevated temperature stresses

Sébastien Guyader (1)

1 ASTRO - Agrosystèmes tropicaux

Many studies have used epidemic models in conjunction with climate change projections to predict the effects of climate on plant pests, but have focused on the effects of average air temperature, humidity and rainfall. However, in most scenarios climate change is expected to increase the variability in climatic parameters, leading to potentially more extreme records in temperature, rainfall, or drought periods. In this paper, we studied the survival capacity of the anthracnose pathogen Colletotrichum gloesporioides infecting water yam (Dioscorea alata) to prolonged dry periods (6 to 48h) and supraoptimal temperatures (36 to 40°C). Our results show that i) spores of C. gloeosporioides can survive in the absence of leaf wetness for up to 48h and recover a high infectious capacity when water is provided subsequently, and ii) infectious capacity is recovered after high temperature stress of up to 40°C, depending on the strain.

Mots clés: anthracnosis; global change; survival; genêtic variation; water content; heat stress; water stress

Mots clés: dioscorea; résistance à l'humidité; sensibilité à la sécheresse; pouvoir infectieux; diversité génétique; croissance mycélienne; humidité; survie; anthracnose; spore; température; dioscorea alata; stress thermique; résilience; changement climatique; pathologie végétale; stress hydrique; colletotrichum gloeosporioides

Domaines: Mycologie; Phytopathologie et phytopharmacie; Milieux et Changements globaux

Sébastien Guyader. Resilience of Colletotrichum gloeosporioides strains infecting yams to dry period and elevated temperature stresses. 53. Annual Meeting of the Caribbean Food Crops Society (CFCS), Caribbean Food Crops Society (CFCS). INT.; University of Puerto Rico. College of Agricultural Sciences of the Mayagúez Campus, PRI., Jul 2017, Isla Verde, Puerto Rico. ⟨hal-01985340⟩