Embryo rescue secara in vitro dan produksi bibit aren (Arenga pinnata (Wurmb) Merr.).

Abstract

Sugar palm is a member of Arecaceae (palmaceae) originated from Indo- Malayan archipelago. Sugar palm may have important position as biofuel producing crop. Hence, research and development of sugar palm need to be done. Availability of planting material is one of significant constraints to develop sugar palm for cultivation and breeding program. The main constraints of planting material (sugar palm seedlings) in Indonesia are the seed dormancy and the use of physiologically mature seed as planting material. Embryo rescue technique can be applied as a breakthrough to obtain sugar palm seedlings in a relatively short time. The objectives of the experiment were to evaluate: 1) the effect of zygotic embryo age and basal medium composition on germination and development of rescued zygotic embryo of sugar palm, 2) the effect of pre-treatment and cytokinins and 3) the effect of PGR combination (auxin with or without cytokinin) in vitro embryo culture and seedlings production of sugar palm. In exp. 1, zygotic embryos isolated from immature and mature sugar palm fruit were cultured on Y3 or WPM medium without of plant growth regulators. In exp. 2. sub-unit 1, immature zygotic embryos with or without pre-treatment were cultured onto Y3 medium containing cytokinin in the form of coconut water (100, 150 and 200 ml/l) or BAP (5 ppm). In exp. 2. sub-unit 2, addition of NAA (1 or 5 ppm), kinetin (5 ppm), BAP (5 ppm), a combination of NAA (1 or 5 ppm)+kinetin (5 ppm), or NAA (1 or 5 ppm)+BAP (5 ppm) in Y3 medium for plantlet regeneration. The result showed that the viability and germination of immature zygotic embryo (92%) was better than the mature one (72%). On the other hand, the composition of the basal medium (Y3 or WPM) did not significantly affect embryo germination. Some of the culture zygotic embryo developed abnormal development of haustorium and cotyledonary petiole, at 32% and 26%, respectively. The percentage of planlets from zygotic embryo in this experiment range from 6%-25%. The results showed that cytokinin (coconut water or BAP) did not affect growth of the rescued zygotic embryo, whereas immature embryo with pretreatment led to the highest shoot and root formations, respectively. On the other hand, addition of PGR (auxin with or without cytokinin) showed positive effects on length of root from the zygotic embryos. A combination of NAA (5 ppm)+BAP (5 ppm) gave the highest number planlets. The plantlet of sugar palm were successfully regenerated from rescued embryos and transferred into soil.