Transgenic approach manipulating gene expression for trait modification is one of the effective strategies for switchgrass breeding and genetic improvement (Sticklen 2006; Gressel 2008; Li and Qu 2011; Mann et al.

2012) . As one of the important regulatory factors in plants, miRNA genes and their targets are potential candidates for this purpose. Although little is known about the functions of miRNAs in switchgrass, several miRNA families are evolutionarily conserved in plant species, so is the miRNA — mediated regulatory mechanism (Jones-Rhoades et al. 2006; Chen 2009; Voinnet 2009; Cuperus et al. 2011). Therefore, it is possible to make use of the miRNAs whose functions have been identified in other species to modify this bioenergy crop.