Judul: Keragaman Genetik Aksesi Pinang (Areca catechu L.) Asal Papua, Sulawesi Utara, dan Sumatera Utara Berdasarkan Karakter Morfologi dan Penanda RAPD (Random Amplified Polymorphic DNA)
Abstrak: Areca nuts (Areca catechu L.) is a palm plant that has not been studied intesively than other palm crops (coconut). Areca nuts is used as ingredients of medicines, cosmetics, and ceremonial, as well as a symbol of social and cultural relationship. The objectives of these studies were to explore genetic diversity of areca nuts accessions (Areca catechu L.) from Papua, North Sulawesi and North Sumatera that were collected and planted in Experimental Station Kaiwatu, Indonesian Coconut and Palmae Research Institute (Balitka), Manado. These studies were conducted in July 2010 - June 2011. Plant morphological characters were observed and measured and DNA markers were identified using two primers RAPD. Data were analyzed using the program NTsys 2.02. Morphological characters for eight accessions of areca nuts has a similarity level 6%. However, the similarity of six areca nuts accessions, representing three provinces, based on DNA markers was 49%. Individual areca nuts palms are not groupped into their accession, based on either morphological or DNA markers.
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Judul: Keragaman Genetik Nenas (Ananas comosus (L.) Merr.) berdasarkan Penanda Morfologi dan Amplified Fragment Length Polymorphism (AFLP)
Abstrak: Information on genetic diversity is essential in breeding program. Characterization of germplasm for providing genotype variation data can be accomplished by phenotypic or genotypic assessment. The aim of this research was to know the genetic diversity among 21 pineapple accessions from Sumatera, Kalimamtan, Sulawesi, Irian Jaya, Jawa Barat, Bali and Jepang based on morphological character and Amplified Fragment Length Polymorphism (AFLP). The morphological data consisted of length, width, spine position and coloration of leaves. The data were categorized into class data and converted to binary form. Two selected primers P11 and M48 were used to generat AFLP markers. The twenty nine AFLP fragments were scored as binary form based on the presence (1) and absence (0) of each fragment. Similarity matrix was obtained to perform cluster analysis based on Dice coefficient. Dendrogram was constructed through clustering analysis using SPSS-13 software. An integrated similarity analysis of morphological and AFLP data showed that similarity coefficient among the 21 accessions ranged between 0.67-1.00. All the 21 accessions were clustered into tree groups at similarity index of 0.74. The first group consisted of 17 accessions, the second group consisted of 3 accessions and the third group contained 1 accession. However, all 21 accessions were closely related each other at 0.67 similarity coefficient.
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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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