Identification and characteristics of Stagonosporopsis cucurbitacearum pathogenic factors influencing pumpkin seeding survival in north-east China

Abstract

The parasitic pathogenic fungus Stagonosporopsis cucurbitacearum (Sc.) is the main cause of pumpkin gummy stem blight (GSB), one of the most devastating pumpkin crop diseases in north-east China. In the present study, transcriptome analyses of the GSB-susceptible strain commonly grown in that region, zq-1, were performed to identify differentially expressed genes (DEGs) relevant to GSB infection. Using RNA-seq of six fungal samples, we obtained 44.62 Gb of clean sequence data with a Q30 base percentage of 92.38% or higher. We carried out functional annotation by comparing sequences against NR, Swiss-Prot, KEGG, COG, KOG, GO, and Pfam databases and obtained annotation results for 38,110 unigenes. From these unigenes, a total of 341 DEGs were identified and subjected to GO functional annotation and KEGG pathway analysis. Subsequently, 52 genes possessed putative pathogenic functions, with 34 genes assigned to molecular function (including hydrolase, protein kinase, phosphatase, cellulase, etc.), 15 genes assigned to biological process, and 3 genes assigned to mitogen-activated protein kinase pathways, ABC transport proteins and cellular endocytosis. Identification of DEGs should enhance our understanding of pathogenic genes involved in pumpkin infection by Sc. and should facilitate the systematic investigation of pathogenic gene expression patterns and host–pathogen interactions.