A Comparative Study of Host Response against Macrophomina phaseolina Infection in Sensitive and Resistant Jute (Corchorus sp) Species Unravels a Possible Defense Mechanism

Abstract

Plants are inherently able to save themselves from any unfavorable conditions. However, they fail to exert ample response when encountered with pathogens like Macrophomina phaseolina which infects more than 500 crops. Wild plant species empowered by superlative mechanisms can conquest deadly pathogens, an example of which is C. trilocularis, a jute plant, resistant to this necrotrophic fungal pathogen. This study tried to ascertain the underlying resistance mechanism regarding the systemic acquired resistance (SAR) and cell wall fortification. Identification and characterization of genes involved in the systemic acquired resistant pathway implicated an activity of these genes with a basal expression in resistant species but irregular in the sensitive one (C. olitorius). Real-time expression analysis of genes involved in the synthesis of cell wall components like cellulose, hemicellulose, and lignin along with chemical and microscopic examinations signified preeminent lignification in C. trilocularis. However, this vital plant cell wall component was found to decrease in C. olitorius. The present investigation provided a deep insight into the defense strategy employed by the two species of jute at the molecular level. This study is expected to help in improving the fungal resistance of susceptible but farmer popular jute species. The same should be applicable to other vulnerable crops as well. Understanding how the pathogen is recognized, and an effective defensive response mounted, could ultimately lead to the development of novel strategies for providing durable plant resistance.