Abstract: Dongnongdongmai 1 is the first cultivated winter wheat variety that can survive in Heilongjiang province. The cold tolerance of the tillering nodes directly affects the ability of overwintering. MicroRNAs (miRNAs) are a class of small non-coding endogenous RNAs with a critical role in development and environmental responses in plants. We analyzed the small RNAs of tillering nodes of Dongnongdongmai 1 under 5°C and –10°C. Under 5°C condition, we detected 2 229 955 unique sequences and 35 known miRNAs, which can be grouped into 30 miRNA families, with abundance ranging from 1 to 173 810. Under –10°C condition, we detected 3 721 449 unique sequences and 29 known miRNAs, which can be grouped into 24 miRNA families, with abundance ranging from 1 to 105 868. Target gene prediction revealed 53 putative target genes from the 30 miRNAs at 5°C, some of which were involved in transcription regulation, metabolism, stress response and signal transduction. Both types and abundance of known miRNAs differed in Dongnongdongmai 1 grown at 5°C and –10°C.

Key words: winter wheat, Dongnongdongmai 1, microRNA, high throughput sequencing, bioinformatics