De novo transcriptome sequence and identification of major replanting-related genes and miRNAs in Polygonatum odoratum

Polygonatum odoratum is a historically traditional Chinese medicine plant and can be eaten directly. Howerver the replanting diseases like other Chinese medicine lead it difficulty to cultivate on a large scale. In this study, we used the high-throughput sequencing of miRNA and mRNA to found out some clues of the replanting diseases. the mRNA and miRNA library of leaves and root from first crop plants and continuous crop plants were used to carry out the second-generation sequencing. Based on the bioinformatics analysis, total 365 miRNAs were detected and of which 81 were considered as novel miRNAs. A total of 126 and 142 miRNAs were identified in leaves and roots respectively. In the mRNA field, 13798 and 15788 genes were regulated in leaves and roots, respectively. Furthermore, 3 and 4 miRNAs and their targets were analyzed by qRT-PCR; meanwhile, lots of redox related genes in roots and metabolic pathway genes in leaves were different in first crop plants and continuous crop plants. This study not only provide a thorough list of miRNA and mRNA which related to replanting diseases, but also suggest a possibility that the change in the soils may lead to the disorder of redox in the root cause the slow growth in the continuous crop plants. This signaling pathway may indicate a supposed to heal the replanting diseases.