Transcriptome Sequencing for Dissecting Growth Mechanism of a Commercially Important Sub-Tropical Bamboo - Dendrocalamus hamiltonii

Bamboo is one of the fastest growing plants due to rhizome dependence. Despite, transcriptome sequencing of culms growth in temperate bamboo species (P. edulis), efforts have not being made on genetic research in sub-tropical/tropical bamboo species, partway because of the lack of genomic resources. India is one of the major hot spot for bamboo genetic resources with more than 130 species. Dendrocalamus hamiltonii has high commercial and ecological value. It attains maximum height within a period of 2-4 months of monsoon. Current study focuses on de novo transcriptome sequencing of D. hamiltonii to understand growth behavior using Illumina GA II sequencer. Comparative expression profiles of growing and mature shoot and rhizome would enable us to identify genes related to growth. In all, 29.3 million and 37.2 million reads of various stages of shoot and rhizome were generated. Read assembly produced a total of 39,603 contigs (average length = 553 bp). Among them, 29,032 showed significant hits against non-redundant protein database. 50,551 GO terms were assigned to 15,169 contigs. Of these, cellular component were the majority (18,445), followed by biological processes (18,420) and molecular function (13,686). Significant proportion of genes related to growth, developmental process, cell signaling and response to stimulus showing differential expressions were identified. Further, a total of 1,054 unique SSR primer pairs were developed which can be utilized for genetic diversity, phylogenetic and genetic mapping studies of bamboo.