RNA seq of poplars
The total RNA of the samples was extracted with Plant Total RNA Extraction Kit (DP432, Tiangen, China) according to the manufacturers instructions. After agarose gel electrophoresis and spectrophotometer detection (NanoDrop 2000, Thermo Fisher, USA), qualified RNA samples were then sequenced on the Illumina HiSeq XTen platform with pair end 150 bp (PE150) by Novogene Co, Ltd. (Beijing, China).  In order to obtain high-quality dataset, adapters of sequences were cut and low-quality reads were removed using FastQC (v0.11.53)