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: Genetic diversity analisis on pineapple (Ananas comosus (L.) Merr.) by random amplified polymrphic dna (RAPD)
Abstrak: Pineapple is belong to the Bromeliaceae, a large family of American tropics (only one species originated from Africa) which has 45 genera and 2 000 species. Out of six species of pineapple, Ananas comosus (L.) Merr. is the only species grown commercially for its fruit (Nakasone and Paull, 1998). To date, world cultivation just based on six cultivars, i.e., Cayenne, Queen, Singapore Spanish, Red Spanish, Abacaxi and Perolera, while the first three have been the genetic base of distribution from the original area. In Indonesia, cultivars that recommended by Department of Agriculture are only Queen (Bogor pineapple and Palembang pineapple) for fresh fruit and Cayenne (Smooth or Lisse) for processing uses and assumed to have low genetic variability. In this study, 17 accessions of pineapple (Ananas comosus (L.) Merr.) were evaluated for their morphological performance and subjected to analysis of Random Amplified Polymorphic DNA (RAPD). Eight morphological characters of the accessions were measured to examine their morphological relationship. For RAPD analysis, thirteen primers of 10-mers were used to amplify the genomic DNA of the pineapple accessions. Out of them, three random primers yielded monomorphic products while the remaining amplified a total of 20 (87%) fragments, all of which were polymorphic, with an average of 1.77 fragments per primer. A dendogram based on UPGMA-link method and principal component analysis (PCA) plots were examined the clustering pattern and distribution of the accessions, both for morphological characters and amplification products. As the result, RAPD analysis showed higher coefficient of similarity between pineapple accessions tested rather than morphological's, which may indicate the high environmental influence on the morphological performance. This study was demonstrated that RAPD analysis was able to detect genetic similarity among accessions in one species, eventhough among all primers used, there was no single primer could distinguish between Queen and Smooth Cayenne group of pineapple tested. ...
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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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