Obstruction of Signal Transduction between Faba Bean and Rhizoctonia Solani during Pathogenesis and its Impact on Root Rot Disease

Abstract

The fungus Rhizoctonia solani Kuhn is one of the most important soil borne plant pathogens. It infects many host plants causing very serious syndromes. In our previous study it was found that R. solani senses its host even when the host was away from the pathogen which reflected on its skeleton. It was postulated that the pathogen feels its host by different agent emitted from the host plant (faba bean). So, it was postulated if it could obstruct these signals, it could affect the pathogenecity of the pathogen. To accomplish this mission, seeds of faba bean were coated by gum Arabic then subjected to the pathogen either in vitro or under green house conditions. In vitro, the pathogen freely senses its host, infected it causing severe symptoms, in comparison to coated cotyledons by gum Arabic, where the pathogen difficulty reach the host and disease symptoms were very weak. Under plastic house conditions, coated seeds or not were planted in sand culture infested by the pathogen. Disease index was very low on root system of coated seeds in comparison to roots of non coated seeds. This action was reflected positively on plant morphology.