Plant defence against Botrytis cinerea, a ubiquitous pathogenic fungus, is known to depend upon the mobilisation of sugars which provide energy and carbon skeletons for the production of antifungal compounds.
Lecompte et al. hypothesise that glucose and fructose could play distinct roles in plant defence, showing that disease severity is highly correlated to the relative fructose content in tomato stem tissues, defined as the proportion of fructose in the plant soluble sugar pool. Conditions of higher susceptibility are associated with glucose accumulation in infected tissues. The physiological meaning of this distinct use of sugars for defence remains to be determined.
This paper is part of the Annals of Botany Special Issue on Plant Immunity, and Open Access so you can view it freely.