RNA-seq analysis of soybean (Glycine max) responding to Phytophthora sojae

Phytophthora sojae is a devastating pathogen of soybean [Glycine max (L.) Merr.] that causes Phytophthora root and stem rot (PRR) on soybean plants worldwide. The pathogen leads to evident differentiation of pathogenicity which brings some difficulties to the control of the disease. Soybean germplasm plays an important role in disease resistance to P. sojae. To understand the role of soybean in the pathogen differentiation of P. sojae, transcriptome sequencing and biological information technology were used to analyse the difference in transcriptional level of soybean response to P. sojae infection by two isolates BB8 and BZ9 with different pathogenicity. A total of 1596 differentially expressed genes (DEGs) were screened from the soybean plants treated with the strong pathogenic isolate BB8 and weak pathogenic isolate BZ9, of which 256 were upregulated and 1340 were downregulated in BZ9 treated samples. Gene Ontology analysis revealed that the highly enriched terms annotated in biological processes were metabolic process, cellular process and single-organism process. Kyoto Encyclopedia of Genes and Genomes pathways were distributed primarily in metabolism, environmental information processing and cellular processes. Photosynthesis-antenna proteins, photosynthesis, phenylpropanoid biosynthesis, carbon fixation in photosynthetic organisms, plant hormone signal transduction, flavonoid biosynthesis, carbon metabolism and nitrogen metabolism were the most substantial metabolic pathways. Ten candidate DEGs were selected and their expression levels were detected via fluorescence quantitative polymerase chain reaction. The expression trends were basically consistent with the results of RNA-seq detection, confirming the reliability of RNA-seq data. Taken together, this was the report on the transcriptome analysis of soybean in response to P. sojae using high-throughput sequencing. A number of DEGs and pathways were discovered, which provided valuable information for obtaining high-quality soybean resistance resources.