Heterosis continues to be utilized widely in the breeding of maize and other crops, and plays an important role in increasing yield, improving quality and enhancing stresses resistance, but the molecular mechanism responsible for heterosis is far from clear. conserved maize miRNAs were co-detected in the hybrid and parental lines. Most of these miRNAs were expressed non-additively in the hybrid compared to its parental lines. These results indicated that miRNAs might participate in heterosis during maize germination and exert an influence via the decay of their target genes. Novel miRNAs were predicted follow a rigorous criterion and only the miRNAs detected in all three samples were treated as a novel maize miRNA. In total, 34 miRNAs belonged to 20 miRNA families were predicted in germinating maize seeds. Global repression of miRNAs in the hybrid, which might result in enhanced gene expression, might be one reason why the hybrid showed higher embryo germination vigor compared to its parental lines. Introduction Heterosis is usually defined as the superior performance of F1 hybrids compared to their parental inbred lines . The phenomenon can be manifested in many phenotypes such as strong growth vigor, increased herb height, and high yield. Utilization of FAE heterosis in many agronomically important crops, such as maize and rice, provides higher yields than real lines; therefore many researchers have sought to elucidate the molecular mechanism of heterosis. Three major hypotheses have been proposed to explain the genetic basis of heterosis, the dominance  namely, overdominance , and epistasis hypotheses . Maize is certainly the right model for exploration of the hereditary system of heterosis, since it includes high degrees of phenotypic, allelic , transcriptional C, and translational  deviation and the prepared option of maize genomic details. In maize, heterosis-related QTLs have already been mapped onto the genome, but this system depends on marker-assisted selection , and heterosis-related protein and transcripts have already been captured by high-throughput genome sequencing and 2-DE analysis C. However, due to its complicated character, the genetic mechanism underlying heterosis in maize is definately not understood clearly. The primary problems is certainly that manifestation of heterosis shows improved quantitative phenotypes environmentally, due to complicated molecular gene and occasions connections, so a significant gene or gene pathway by itself is certainly unlikely to signify the hereditary basis of heterosis in maize. MicroRNAs (miRNAs) are around 21-nucleotide non-coding RNAs that play vital assignments in the legislation of gene manifestation in the post-transcriptional level, and are especially important in epigenetic gene rules. In vegetation, cleavage of the prospective mRNA appears to be the predominant method of post-transcriptional WAY-600 regulation, yet flower miRNA-guided gene silencing has a common translational inhibitory component . Flower miRNA-guided gene rules is definitely involved in multiple developmental processes, such as organ polarity , leaf growth , sex dedication , and male or female sterility . One maize miRNA, miR167, was over dominantly induced in samples of kernels 10 d after pollination between H99 B73 and its parental inbred lines, which led to the WAY-600 suggestion that miRNAs might be involved in the rules of heterosis-related genes . The best starting point for exploration of the genetic mechanism of heterosis in the molecular level is definitely to focus on a simple trait that is hardly ever affected by environmental variability or additional traits . Recently, it was reported that maize embryos soaked for 24 h display heterotic behavior , and that unique difference in germination vigor between hybrids and their parental inbred lines were exhibited; the embryonic tissues within this constant state are hardly influenced by dosage-related effects in the triploid endosperm and environmental effects. In this scholarly study, miRNAs in embryos WAY-600 of the maize cross typ