Abstract: It was found that the contents of dry matter，soluble sugar and soluble protein were enhanced with the growth and development of lotus（Nelumbo nucifera Gaertn）rhizome，especially in the later enlarging period of rhizome. In present study，transcriptome sequencing technologies were used to analysis the genes involved in development of lotus rhizome included 35 hormone related protein genes，4 light induced protein genes，35 starch metabolisms related genes and 1 tuberization gene，which might be related to enlarging of lotus rhizome were found. The result of digital gene expression profiles showed that ten Patatin family genes（Lrplp6，Lrplp9，Lrpfp1，Lrprp，Lrpfp2，Lrplp4，Lrplp5，Lrplp8，Lrpp，Lrplp2）and five starch metabolism related genes（Lrgbss，Lrsbe1，Lrsbe2，LrsbeII，LrsbeIII）significantly changed their expression levels with at least 3 fold in the later period compared with the initial period，while other genes did not obviously alter their expression. The result of Lrplp8 and Lrgbss temporal and spatial expression by semi-RT-PCR in lotus root was similar to the results revealed by digital gene expression profile，suggesting that these two genes were highly correlated with rhizome enlarging. Therefore，we speculated that above 10 Patatin genes and 5 starch metabolism genes played important roles in rhizome enlarging of lotus root.

Key words: lotus root, rhizome, gene expression, hormone, regulation