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: Analisis keragaman genetik nenas (Ananas comosus (L). Merr) berdasarkan penanda morfologi dan penanda RAPD
Abstrak: Keragaman genetik nenas pada kebun koleksi PKBT dapat diungkap melalui analisis morfologi dan molekuler. Penanda yang dapat digunakan untuk mengetahui keragaman genetik nenas adalah RAPD ( Random Amplified Polymorphic DNA). RAPD merupakan teknik yang lebih cepat dan mudah dilakukan karena tidak perlu diketahui sekuen DNA sebelumnya dan material tanaman yang dibutuhkan lebih sedikit. Penelitian ini bertujuan menganalisis dan mengevaluasi keragaman aksesi nenas berdasarkan penanda morfologi dan genetik serta mengetahui keragaman genetik nenas berdasarkan penanda morfologi dan penanda RAPD koleksi Pusat Kajian Buah-buahan Tropika (PKBT) Keragaman morfologi dapat diamati pada penanda morfologi sebanyak 31 karakter meliputi organ : (1) daun yaitu 15 karakter, (2) buah yaitu 16 karakter dan diperoleh 116 karakter pembeda. Hasil analisis pengelompokan diperoleh sebanyak 3 kelompok pada tingkat kemiripan 0.62 yaitu (1) grup A meliputi C-KAS, SC-JPG, C-LMPG1, C-LMPG3, SC-SMDG, Q-KTM1, Q-KTM2, QOGIL, Q-RIAU, QH-BBEL, Q-BLI, QC-P18, QC-AZRI, QC-V49, C-RNIS, QCP5/ 12, CNN, C-SMUT2, QC-P10, SC-WNSBO, C-FLPN, QC-III, QC-P14 (2) grup B meliputi C-SMUT, C-BNHYU, SC-NAD, C-SMDU, SC-SMUT3, SC-PRBA dan (3) grup C meliputi C-MNDO, C-PAK, SC-DSBG. Analisis molekuler terhadap 32 aksesi menghasilkan 50 pita yaitu 47 pita polimorfik (98%) dan pita monomorfik sebanyak 3 pita (2%). Hasil analisis pengelompokan skor pita DNA dengan menggunakan program NTSYS, diperoleh 3 grup pada koefisien kemiripan 0.66 yaitu (1) grup A meliputi C-KAS, C-SMUT, C-PAK, QC-V49, Q-KTM2, C-LMPG3, C-SMUT2, C-SMDU, Q-RIAU, QC-AZRI, C-BNHYU, C-FLPN, Q-KTM1, Q-BLI, Q-MNDO, C-LMPG1, QC-P14, (2) grup B meliputi QC-P5/12, QC-P10, QC-III, C-DSBG, SC-SMUT3,QC-P18, Q-OGIL, SC-NAD, SC-PRBA, C-RNIS, SC-SMDG, SC-WNSBO, SC-JPG dan (3) grup 3 meliputi CNN. Penggabungan data penanda morfologi dan penanda molekuler memberikan informasi secara fenotipik dan genotipik. Karakter yang digunakan adalah penggabungan 31 karakter morfologi dan 10 primer yang menghasilkan 50 pita, sehingga total gabungan karakter adalah 81. Hasil analisis dengan menggunakan program NTSYS pada koefisien kemiripan 0.61, diperoleh dendrogram membentuk 3 grup, yaitu (1) grup A meliputi C-KAS, C-SMUT, CPAK, C-BNHYU, C-SMDU, C-FLPN, QC-III, C-DSBG, Q-KTM1, Q-KTM2, CLMPG3, C-SMUT2, Q-RIAU, Q-BLI, QC-V49, QC-AZRI, C-LMPG1, C-RNIS, QH-BBEL, Q-OGIL, QC-P18, QC-P10, QC-P5/12, CNN, SC-SMDG, SC-JPG, SC-WNSBO, QC-P14 (2) grup B meliputi Q-MNDO, SC-NAD, SC-PRBA dan (3) grup D meliputi SC-SMUT.
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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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