Analisis molekuler tanaman padi transgenik Cv. Rajalele yang mengandung gen chil

Abstract

This research showed that Indonesian indigenous rice cultivar Rajalele was successfully transformed with a rice-origin chitinase gene chiI. The chiI gene cassette flanked with CaMV 35s promoter and terminated by nos terminator. The construct gene was introduced into embryogenic calli employing Agrobacterium tumefaciens transformation system. The integration of recombinant DNA into the rice genome was analysed using three methods, i.e., polimerase chain reaction (PCR), GUS assay and chitinase assay. Results of the GUS assay showed that 100% of the transformed calli expressed gusA on three day-old calli after co-cultivation. This percentage of expression decreased to 20-40% on older calli i.e. 15 day-old calli after cocultivation. In the plantlet stage, 0.2% (2 plantlets) and 0.4% (4 plantlets) of the transformed calli derived plantlets gave positive to GUS expression after the X-gluc assay for pESMI-88A and pESMI-88B, respectively. These percentages were unchanged until plant maturity. PCR analysis, using primers specific for chiI gene showed independent lines of trasformants had chiI gene sequences in their genomes. Chitinase assay of mature plants showed that 5 of 25 transgenic plants showed chitinase activities higher than the control plants.