Judul: Effect of Addition of Several Combinations of Growth Regulatory Substances (PGR) and Pre-Treatment Media on In Vitro Growth of Sugar Palm (Arenga pinnata Merr) Zygotic Embryos.
Abstrak: Aren (Arenga pinnata Merr) merupakan famili Arecaceae yang tumbuh soliter. Tanaman ini memiliki tandan yang ditumbuhi oleh buah aren. Buah aren memiliki embrio yang dapat digunakan sebagai bahan perbanyakan secara generatif. Perbanyakan bibit aren melalui embrio diharapkan dapat menghasilkan bibit secara cepat dan berkualitas. Tujuan penelitian ini untuk melakukan evaluasi pengaruh pemberian kombinasi ZPT dan media pra perlakuan pada tanaman aren secara in vitro dalam petumbuhan dan perkembangan membentuk tunas. Hasil penelitian menunjukkan bahwa pemberiaan kombinasi ZPT dan penggunaan media pra perlakuan secara masing-masing berpengaruh dalam pertumbuhan embrio aren. Pemberian kombinasi terbaik dengan BAP 7,5 ppm + IAA 2 ppm menunjukkan pengaruh yang nyata terhadap kontrol dalam pertumbuhan kecambah embrio aren hingga membentuk tunas dan media tanpa pra perlakuan menunjukkan hasil terbaik dalam pertumbuhan embrio menjadi tunas. Pemberian ZPT dan pengunaan media pra perlakuan berpengaruh dalam pertumbuhan embrio aren., Aren (Arenga pinnata Merr) is a solitary growing family of Arecaceae. This plant has bunches overgrown with palm fruit. Palm fruit has an embryo that can be used as a generative propagation material. Propagation of palm seeds through embryos is expected to produce seeds quickly and with quality. The purpose of this study was to evaluate the effect of giving a combination of PGR and pre-treatment media on sugar palm plants in vitro on growth and development to form shoots. The results showed that the combination of PGR and the use of pre-treatment media each had an effect on the growth of sugar palm embryos. Giving the best combination with BAP 7.5 ppm + IAA 2 ppm showed a significant effect on control in the growth of sugar palm embryo sprouts to form shoots and media without pretreatment showed the best results in embryo growth into shoots. The administration of PGR and the use of pre-treatment media had an effect on the growth of sugar palm embryos.
Keyword: Embryo, in vitro, pre-treatment, sugar palm

Judul: Embryo rescue secara in vitro dan produksi bibit aren (Arenga pinnata (Wurmb) Merr.).
Abstrak: 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.
Keyword: auxin, coconut water, cytokinin, embryo rescue and sugar palm

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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