Judul: Identifikasi Morfologi dan Marka Genetik Terpaut Sifat Tidak Berbunga Jantan pada Mutan Pisang Kepok
Abstrak: Bananas is an important horticultural commodity in Indonesia. However, the improvement of production capacity of cooking banana is hampered by Blood Disease Bacterium (BDB). Cooking banana such as kepok banana is very important commodity in several areas in eastern part of Indonesia for cash crop as well as for daily consumption. Since late 90s, production of kepok banana from Kalimantan drastically declined as a result of devastating outbreak of BDB. As a result many farmers are losing their main source of income. The disease is quickly spread at about 100 km distance per year as the bacterium is insect transmitted. Disease infection could be reduced by avoiding direct contact between insect vector and male bud by breaking peduncula supporting male bud or by cultivating male budless kepok banana mutant. Recently Centre for Tropical Horticultural Studies (PKHT) at Bogor Agricultural University (IPB) already collected several male budless kepok banana mutants with good eating quality named Unti Sayang (US-1). However, the genetic stability of these mutants is still unknown. Therefore, discovering DNA markers related to male budless character in kepok banana is very important to establish a stable mass propagation system for male budless character on kepok banana, and valuable for science to elucidate male budless mechanism in banana. The objectives of this research were to identify morphological characters and RAPD and ISSR markers and develop Pistillata and Agamous gene based moleculer marker related to male budless characters in kepok banana mutant Unti Sayang (US-1). Identification of morphological characters were carried out based on the International Plant Genetic Research Institute (IPGRI) descriptor for banana. The results showed that there is no morphological variation among wild type, mutants and revertrant other than a male bud character. The revertrant mutants were found among planlets derived from the sixth sub culture and second generation of suckers. Polymerase Chain Reaction (PCR) was used to amplify DNA of 24 plants derived from the first and sixth sub cultures using 20 RAPD and 12 ISSR primer combinations. Those RAPD and ISSR primers produced monomorphic DNA bands with the amount ranged from 2 to 6 and 6 to 8 per plant, respectively. No polymorphism was found between male budless mutants and revertrant mutants. The absence of genetic variation among wild type, mutants and revertrants has been reported in several cases of molecular marker analysis in in vitro cultured banana, although there was a variation in their morphology. Based on the PCR analysis, it was suggested that there was no genetic change between wild type and mutants. However, it is possible that some changes might occurred as point mutation located outside of the priming sites. Male budless characters was suggested to be controlled by Pistillata gene that control petal and stamen formation and Agamous gene for karpel formation. Therefore, the primers based Pistillata and Agamous genes were developed using Musa GeneBank database. PCR analysis using those primer combination have also produced no polymorphic bands among the analyzed banana plants. Carefull nucleotide sequence analysis of both DNA fragments showed three single nucleotide polymorphism between wild type and revertrant mutants at the position of
Keyword: ISSR, Male budless kepok banana, Pistillata, RAPD

Judul: Identifikasi Morfologi dan Marka Genetik Terpaut Sifat Tidak Berbunga Jantan pada Mutan Pisang Kepok
Abstrak: Bananas is an important horticultural commodity in Indonesia. However, the improvement of production capacity of cooking banana is hampered by Blood Disease Bacterium (BDB). Cooking banana such as kepok banana is very important commodity in several areas in eastern part of Indonesia for cash crop as well as for daily consumption. Since late 90s, production of kepok banana from Kalimantan drastically declined as a result of devastating outbreak of BDB. As a result many farmers are losing their main source of income. The disease is quickly spread at about 100 km distance per year as the bacterium is insect transmitted. Disease infection could be reduced by avoiding direct contact between insect vector and male bud by breaking peduncula supporting male bud or by cultivating male budless kepok banana mutant. Recently Centre for Tropical Horticultural Studies (PKHT) at Bogor Agricultural University (IPB) already collected several male budless kepok banana mutants with good eating quality named Unti Sayang (US-1). However, the genetic stability of these mutants is still unknown. Therefore, discovering DNA markers related to male budless character in kepok banana is very important to establish a stable mass propagation system for male budless character on kepok banana, and valuable for science to elucidate male budless mechanism in banana. The objectives of this research were to identify morphological characters and RAPD and ISSR markers and develop Pistillata and Agamous gene based moleculer marker related to male budless characters in kepok banana mutant Unti Sayang (US-1). Identification of morphological characters were carried out based on the International Plant Genetic Research Institute (IPGRI) descriptor for banana. The results showed that there is no morphological variation among wild type, mutants and revertrant other than a male bud character. The revertrant mutants were found among planlets derived from the sixth sub culture and second generation of suckers. Polymerase Chain Reaction (PCR) was used to amplify DNA of 24 plants derived from the first and sixth sub cultures using 20 RAPD and 12 ISSR primer combinations. Those RAPD and ISSR primers produced monomorphic DNA bands with the amount ranged from 2 to 6 and 6 to 8 per plant, respectively. No polymorphism was found between male budless mutants and revertrant mutants. The absence of genetic variation among wild type, mutants and revertrants has been reported in several cases of molecular marker analysis in in vitro cultured banana, although there was a variation in their morphology. Based on the PCR analysis, it was suggested that there was no genetic change between wild type and mutants. However, it is possible that some changes might occurred as point mutation located outside of the priming sites. Male budless characters was suggested to be controlled by Pistillata gene that control petal and stamen formation and Agamous gene for karpel formation. Therefore, the primers based Pistillata and Agamous genes were developed using Musa GeneBank database. PCR analysis using those primer combination have also produced no polymorphic bands among the analyzed banana plants. Carefull nucleotide sequence analysis of both DNA fragments showed three single nucleotide polymorphism between wild type and revertrant mutants at the position of
Keyword: ISSR, Male budless kepok banana, Pistillata, RAPD

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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