Perpustakaan Digital ITB

One of the most popular orchids both as cut flowers and ornamental plants is Phalaenopsis sp. This orchid has beautiful shape, attractive colors, and long-lasting flowers. However, its flowering time is long, therefore it is necessary to start the flowering time faster through genetic engineering by overexpressing the OMADS1 gene (Oncidium Gower Ramsey MADS-box). The OMADS1 gene was chosen because this gene was able to accelerate the onset of flowering time of Oncidium Gower Ramsey, Arabidopsis thaliana, and Nicotiana tabacum by 30%. By isolating and constructing the OMADS1 gene in pBI121 binary vector, it was expected that OMADS1 gene could be expressed in Phalaenopsis sp. through plant transformation with Agrobacterium tumefaciens LBA4404. From this study, the OMADS1 gene has been successfully isolated from the Oncidium Gower Ramsey RNA which was amplified by using specific primers in a Polymerase Chain Reaction (PCR). From the isolation result, it is known that OMADS1 gene size is 849 bp. This gene later on was constructed on pBI121 binary vector using XbaI and XmaI restriction enzymes and T4 DNA Ligase. The recombinant plasmids containing OMADS1 gene furthermore was expressed into Phalaenopsis sp. protocorm using A. tumefaciens LBA4404. According to the results of GUS histochemical assay, GUS gene was expressed in Phalaenopsis sp. protocorm, as indicated by blue spot on putative transformant Phalaenopsis sp. protocorms. The result of this study could be further used for studying the effect of overexpressing OMADS1 gene in Phalaenopsis sp. flowering time and phenotype characteristic.