Curcuma alismatifolia is an important cut flower in Thailand. Tubers, flowers, and potted plants are
exported globally. Since there is limited in colour variation, the production cannot be done all yearround,
and diseases are serious restrictions for export. Hence, challenges of improving the new colour
variety, off-season flower cultivar, and disease-free tuber will lead to the increasing of their value to
meet the market requirements. The study of genes involved in flavonoid pathway (CHS, CHI, and DFR)
and in carotenoid pathway (ZDS) shows that the expression of CHS, CHI, and DFR together is
necessary in order to generate pink, orange, or purple coloured plant tissue. Lacking only one gene in
this group cause the reduction of pigment accumulation which can lead to colour faded or white tissue.
The expression of ZDS is high in yellow to green coloured plant tissue. Therefore, ZDS is involved in
carotenoid biosynthesis resulting yellow pigmentation. Interestingly, the alteration of gene expression
level related with diverse colour pattern in plant might be associated with the difference of promoter
sequences or sequences within the gene. Accordingly, understanding genes involving Curcuma colour
pattern is important since it influences flower colour, which is turn impacts on Curcuma production in
the future. Apart from colour study, the information of flowering genes in Curcuma is needed in order
to develop the new varieties which can be produced all year round. There are two parts of this project,
the study of flowering time physiology using transfer experiment and the study of flowering time gene
expression using transcriptome sequencing. The results from the physiology study show that Curcuma
is a facultative long day plant which flower can be produced quicker under LD condition. Moreover,
RNA-Seq data shows at least 122 differentially expressed genes involved in flowering which related to
carbohydrate metabolism, flowering time, growth and development, and plant defense mechanism. Key
genes can be selected base on the function for further study to improve new Curcuma variety which
can be produced all year-round. For the study of disease-free tuber production, the soilless planting
system is introduced. The results show that plants can be grown in 4-inch standard pot and the most
suitable media for this system is peat moss. After 20 weeks, the plants can be harvested. In conclusionthis research project provides the information about flowering time control in Curcuma, disease-free
tuber production, and genes involving flower colour and flowering time which will be used for further
study to improve new varieties of Curcuma.