Rekayasa teknologi sambung mikro dan setek mikro pada tanaman manggis (Garcinia mangostana)

Abstract

The purpose of this study was to assemble propagation technology in mangosteen plant using micrografting and microcutting. This study consisted of four experimental steps, 1) in vitro bud induction technology development from bud explants of mangosteen seedling shoot, 2) physiology and anatomy studies of micrografting in mangosteen, 3) in vitro medium manipulation on mangosteen microcutting; 4) optimization of microcutting acclimatization on mangosteen with sterile porous medium technique (MSP) / in vitro soil-less propagation (IVS). The results of experiment I showed that the best medium for shoot induction phase was MS + BA 4,0 + TDZ 0,2 mg/l, MS + BA 8,0 BA + TDZ 0,2 or MS + BA 4,0 mg /l. Medium multiplication could not obtain shoot multiplication, only addition of nodes and elongation of shoots. The best medium for shoot elongation was medium MS + BA 1 mg/l + KIN 1 mg/l. Experiment II showed that the rootstock derived from a single intact seed germination was better success than other treatments in almost all the observed variables, such as flush shoot that was better success than dormant shoot. There are several factors that determine the success of micrografting, which is width of meristem encounter between the rootstock and scion, the equal cell growth rate between rootstock and scion cells, as well as the similarity in size and structural congeniality between rootstock and scion. The results of anatomical tissue observation (4 months after micrografting) indicated that there was a good graft union on micrografting. Roostsock and scion xylem tissue were fused perfectly. Experiment III results showed that the concentration of 25% MS medium concentration on various substrates with or without the addition of IBA might cause 50-80% of microcutting rooted with the root length between 1,8 to 4,38 cm. Experiment IV results showed that microcutting carried out using MSP technique could grow roots, even at the microcutting that were untreated with root growth stimulating substances. Microcutting that planted using a MSP technique with IBA and Rootone-F treatments at varied concentrations could cause mangosteen microcutting 100% rooted with the root length from 3,44 to 6,88 cm.