The Effect of Light Colour on Rbcl Gene Expression of In-Vitro Lemba (Curculigo latifolia)

Curculigo latifolia is an endemic species of Borneo Island which has great potential as a medicine or artificial sweetener. However, this species only exists in the wild and is not cultivated. Therefore, in-vitro techniques by controlled environment condition such as light can be use to increase plant productivity. Plants absorb light using various types of photoreceptors and influence gene expression to stimulate physiological responses, including photosynthesis. One of the stages of photosynthesis is the Calvin cycle, where the process of CO₂ fixation catalyzed by the enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). Rubisco is composed of eight small subunits (SSU) and eight large subunits (LSU). LSU is encoded by rbcL and plays an important role in the initiation of carbon fixation. Therefore, this study aims to determine the effect of light type on rbcL gene expression in lemba (Curculigo latifolia). This study used seedling induced from seed grown on MS0 (Murashige and Skoog) media with light treatment of red LED, blue LED, white LED, and white fluorescence. rbcL gene expression were analyzed using Real-Time Quantitative PCR. The results showed that the highest rbcL gene expression is detected in seedlings with blue LED light exposure treatment, which is 3.81 fold. While the lowest was found in seedling exposed to white fluorecent which is 0.37 fold. This discovery is expected to provide insight into the best environmental conditions to optimize the productivity of C. latifolia.