Mycorrhiza-induced protection against pathogens is both genotype-specific and graft-transmissible

Abstract

In addition to the nutrient exchange that is promoted by the arbuscular mycorrhiza symbiosis (AMS) between plants and fungi, AMS triggers mycorrhiza-induced protection against plant pathogens. Although the induction of this protection against diverse plant pathogens has been described for several plant species, it is not clear if its onset differs among genotypes within a species. To address this, we have examined if and how this defense response is triggered by AMS in common bean and tomato. Leaflets from three different genotypes of mycorrhizal common beans and two genotypes of tomato were challenged with the pathogens Sclerotinia sclerotiorum and Xanthomonas campestris pv. vesicatoria, respectively, to determine if disease protection induced by mycorrhiza is genotype-specific.