Judul: Development of organogenesis and somatic embryogenesis regeneration of pineapple (Ananas comosus (l.) Merr.) And early detection to reduce somaclonal variation.
Abstrak: Pineapple is a unique plant belongs to facultative CAM (Crassulacean Acid Metabolism) photosynthesis. It is highly potential to be planted on suboptimal land. Conventionally, it can be propagated from many propagules but their reproductive time is not uniform and this availability is commonly limited in cultivar Smooth Cayenne. Today micropropagation is being used commercially in the pineapple industry abroad but in Indonesia, the industries survive with conventional vegetative propagation because of somaclonal variation. The main goal of the study was to obtain the effective regeneration method of pineapple with high level of seedling production and low level of somaclonal variation, included the artificial seed formation method, the early detection method of somaclonal variation for eliminating undesirable traits during micropropagation, and the method to reduce the level of somaclonal variation during micropropagation. This study was devided into six chapters, included the study of morhogenetic system (with solid and liquid media); direct organogenesis induced by auxin and cytokinin (IAA, IBA, NAA, and BA); indirect organogenesis and somatic embryogenesis induced by 2,4-D, picloram, adenine sulfate, and N-organic compounds; encapsulation and minimal growth induced by paclobutrazol, mannitol, and reduced temperature; morphological and molecular characterization by using RAPD markers; and early detection to reduce of somaclonal variation. Generally, this study has some novelities in the in vitro characterization, the information of the non dead-end mechanism of rooted pineapple explants, the information of the complete events of somatic embryogenesis, the conservation method by minimal growth, and the large number of variants. The result showed that the direct and indirect organogenesis generated high shoot multiplication level. The use of mannitol (4%) was better than paclobutrazol for storing the encapsulated explants for 4 months. The morphological characterization could easily differentiate the normal and the abnormal variants (off-types). The direct organogenesis showed the lower level of variation (1.6%) compare to the indirect organogenesis (2%) and somatic embryogenesis (31.1%). The RAPD analysis strengthened the occurence of somaclonal variation. The use of the new in vitro cultures could reduce somaclonal variation. In conclusion, the direct organogenesis was the effective regeneration method for mass propagation. The morphological characterization of in vitro cultures can be applied as guidance for early detection and elimination of undesirable variants in mass propagation. The in vitro conservation method by mannitol can be applied to store pineapple cultures for medium-term period. The use of the new in vitro population could reduce the level of somaclonal variation.
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Judul: The Effect of Cytokinin and Auxin Treatment in the Multiplication Through in vitro Phase to Acclimatization of Pineapple (Ananas comosus (L) Merr.) cv. Smooth Cayenne.
Abstrak: The mass propagation of pineapple are hampered by low multiplication rate in natural way, therefore in vitro propagation is an alternative to overcome mass production. To support mass propagation then we need the best acclimatization way to support multiplication phase to achieved the highest mass propagation rate. The objective of this research was to elucidate the effect of Cytokinin (BA) and Auxin (NAA) that had been applied during multiplication of sub culture I and sub culture II through in vitro phase to acclimatization of pineapple (Ananas comosus L. Merr) cv. Smooth Cayenne. This research was conducted in greenhouse laboratory at Center for Tropical Fruits Studies, IPB Baranangsiang, Bogor, since July until November 2006. This research used 20 combination of treatment from two factors for each subculture 1 and subculture 2. Each subculture conducted in six groups to accomodate difference planlet’s acclimatization readiness. The first factor was 0,00μM, 4,40μM, 8,80μM, 13,32μM, and 17,76μM of BA, and the second factor was 0,00μM, 0,50μM, 1,00μM, 2,00μM of NAA. Number of leaves and plant’s height were examined every week until 13th week after acclimatization. Examination data were statistically analyzed using Complete Randomized Block Design and the means were compared with Duncan’s Multiple Range Test (DMRT) procedure at 5% level of significance. The result showed that treatment of 17,76μM BA and 2,00μM NAA, and its interactions have the highest score for subculture 1. The result of 2,00μM NAA showed the highest performance for subculture 2. Overall performance showed that subculture 1 has better growth rate than subculture 2.
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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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