Total RNA was extracted from roots of the non-inoculated (NI) and inoculated (I) plants using Trizol reagent (Invitrogen, United States) following the manufacturer’s instructions. Residual DNA in total RNA was further digested by DNase (Invitrogen, United States). Then, the quality of integrity of RNA samples were analyzed using Agilent 2100 Bioanalyser (Agilent, United States). Total RNA from three independent plants in each group was used to construct two cDNA libraries in parallel using the Illumina TruSeqTM RNA-seq library prep kit (Illumina, United States) according to the method described by Sun et al. (2016). The two cDNA libraries were sequenced using the Hiseq 2500 platform (Illumina, United States). The sequencing raw data were processed by removing the low-quality reads, and then submitted into the NCBI database (SRA1).