PROPAGATION OF PITCHER PLANTS (Nepenthes gracilis KORTH. AND Nepenthes reinwardtiana MIQ.) THROUGH CALLUS INDUCTION

In vitro propagation of pitcher plants is still limited only using seeds, while the other in vitro methods using leaf explants such as embryogenesis, organogenesis, and callus culture has not been widely reported. The research aims to study the growth response of leaf explants in two species of pitcher plants (Nepenthes gracilis and Nepenthes reinwardtiana), which formed callus in several treatment media combinations. Leaf pieces were taken from a 4-month pitcher plant culture were grown on the treatment media, namely modified media of Murashige & Skoog with a half concentration (½ MS) added 2.4-Dichlorophenoxoxyacetate (2.4-D) with a concentration of 0, 0.5, 1, 1.5, and 2 mg L-1 and kinetin (0.5 mg L-1). The treatment was then stored in a dark environment to induce callus formation. The observation for 12 weeks showed that the time of callus formation in two species of pitcher plant observed was not significantly different. Both species of pitcher plants begin to form callus in the fourth week after treatment. None of the leaf explants were planted on the control medium without hormones formed callus. The best medium for callus induction in N. gracilis is ½ MS medium added with 2 mg L-1 2,4-D and 0.5 mg L-1 kinetin, with callus morphology brownish-white with friable texture. In comparison, the optimum callus media from leaf explant of N. reinwardtiana has not been obtained yet. Thus further research is still needed.