Comparative Transcriptome Profiling of Resistant and Susceptible Taxodium Trees in Responding to the Infection by Pestalotiopsis maculans

Abstract

With the tolerance of flooding and strong winds, Taxodium has been widely recognized as an ecologically important tree in China. Red blight disease, caused by the fungal pathogen Pestalotiopsis maculans, is known as one of the most severe leaf diseases of Taxodium. However, limited information is available regarding the host plant defense response to this pathogen. To uncover the mechanism of the plant–pathogen interaction, we performed an essential comparative transcriptome analysis of the resistant species T. distichum and susceptible species T. mucronatum after P. maculans infection. A total of 50,763 unigenes were assembled, of which 34,651 unigenes were annotated in eight public databases. Differentially expressed gene (DEG) analysis identified 3420 and 4414 unigenes in response to infection in T. distichum and T. mucronatum, respectively. The transcriptome analysis exhibited differential expression patterns in the two species in response to the infection. Moreover, this study first found that, compared to susceptible T. mucronatum, T. distichum can effectively perceive the invasion of P. maculans and make a valid response through SA signal pathway. These data provided not only new insights into the resistance mechanisms in the highly resistant species but also promising genetic resources for improving the fungal pathogen tolerance in Taxodium breeding.