Local BLAST searches were conducted using the BLAST-2.2.28+ package (ftp://ftp.ncbi.nlm.nih.gov/blast/executables/blast+/LAT- EST/). ClustalX, integrated in the Bioedit software, was used for multiple alignments to identify and remove repeated sequences. The online RNAfold server and Mfold 3.2 were used to predict the secondary structures of putative pre-miRNAs (http://rna.tbi.univie. ac.at/cgi-bin/RNAfold.cgi). The miRNA target search was con-ducted using the plant small RNA target analysis server (psRNA- Target; http://plantgrn.noble.org/psRNATarget/) (Dai and Zhao, 2011) and PsRobot (http://omicslab.genetics.ac.cn/psRobot/). The gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) orthology annotation were conducted on an integrated online KOBAS 2.0 server (http://kobas.cbi.pku.edu.cn/home.do) and Blast2go software.