Transcriptomic approach to address low germination rate in Cyclobalnopsis gilva seeds

Cyclobalnopsis gilva is a woody plant with lower seed germination rate in its natural habitats as compared with other plants. The regulation at transcriptional level to of seed germination in C.gilva is yet to be discovered. Illumina HiSeq 2500 platform was performed to investigate the transcriptome of germinated and non-germinated seeds of C.gilva. A total of 40,782 differentially expressed unigenes (DEGs) were identified in germinated and non-germinated seeds and compared with the control. Carbohydrate metabolisms were enriched significantly through the analysis of KEGG pathways of DEGs. The physiological parameters and mRNA expression levels relevant to carbohydrate metabolisms including glycolysis and TCA cycle, and sucrose and starch metabolism were found to be poor in non-germinated seeds. The consistent results of the transcriptomic data, physiological analyses, and mRNA expression levels suggest that C.gilva seeds fail to germinate due to the lower activity of carbohydrate metabolism. Our findings will expand the knowledge on the transcriptional responses of respiratory pathways, sucrose, and starch metabolism related to lower seed germination rate of C.gilva.