Judul: Studi fenologi pembungaan dan keragaman genetik menggunakan marka morfologi dan marka molekuler pada tanaman jarak kepyar (Ricinus communis L.)
Abstrak: This study was aimed at determining flowering phenology, characterizing and analyzing the diversity of phenotypes based on morphological and molecular markers (RAPD), to provide basis for the development of new varieties of castor (Ricinus communis L.) in Indonesia. The plant material for flowering phenology was PRO accession, and 14 castor accesions of IPB collection were used for genetic diversity study. The first leaf of the sprouts was sampled for DNA extraction then used in RAPD analysis. The eight primers used in this study were OPE-3, OPE-19, OPE-20, OPH-13, OPH-14, OPM-2, OPM-5, and OPM-8. The observation on flowering phenology showed that castor was a monocieous plant indicating a cross-pollinated species. The PRO had inflorescence type 1 (gradient monoecism) according to Shifriss in William (1967) in which female flowers were located at distal part and male flowers were at proximal part. Flowers are incomplete and imperfect. Female flowers (averaged of 20 flower/raceme) opened for 3-6 days followed by male flowers averaged f 52 flower/raceme for 1-2 days. Fruit set was 100%, and fruit development last about 40 days. Based on morphological markers of plant height, petiole length, leaf length and leaf width, 100 grain weight, grain length, grain width, and grain thickness, the 14 accessions were significantly diversed. Weight of 100 grains of seed characters were supposed to be for selection because its high heritability value and wide genetic variability coeficient (KKG). There were correlation between characters of width and length of leaves (97%), plant height and stem diameter (86%), petiole and leaf length (90%), as well as petiole length and leaf width (88%), and seed shape and mature petiole color (83%). At similarity coefficient of the morphological characters (qualitative) of 0.85, the 14 accessions were classified into 6 groups i.e. group 1 (BAG-1, PHIL-5, GRE, THAI-101, CIB-1, Sur, and PHIL-4), group 2 (plam-1, PHIL-2, and LAB-1), group 3 (PHIL-13), group 4 (PON-2), group 5 (PRO), and group 6 (TAN-1). Primers amplification produced 49 bands comprising of 36 polymorphic bands (73.47%) and 13 monomorphic bands (26.53%). At 0.85 coefficient of similarity of molecular characters, the 14 accessions were classified into 5 groups, i.e. group 1 (plam-1, PRO, GRE, CIB-1, LAB-1, BAG-1, PHIL-4, PHIL-5, and PON-2), group 2 (THAI-101 and TAN-1), group 3 (PHIL-13), group 4 (PHIL-2), and group 5 (Sur). Characters of juvenile stem color, juvenile petiole color, and mature stem color can be used as morphological markers, as well as OPH-14 primer can be used as molecular markers to classify accessions. PHIL-13 had the potential character to be used as germplasm in further plant breeding activities.
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Judul: Analisis Keragaman Genetik Jarak Pagar (Jatropha curcas L.) berdasarkan Karakter Morfologi, Agronomi dan Marka RAPD
Abstrak: Jarak pagar (Jatropha curcas L.) merupakan salah satu tanaman prioritas penghasil bahan baku bioenergi yang dikembangkan di Indonesia maupun dunia. Salah satu kebijakan pengembangan penyediaan tanaman jarak pagar yang ditempuh oleh pemerintah adalah penyediaan bahan tanam jarak pagar unggul yang telah teruji adaptabilitasnya, didukung dengan paket teknologi yang tepat guna. Dalam usaha penyediaan bahan tanam jarak unggul diperlukan kegiatan perbaikan genetik melalui pemuliaan tanaman untuk mendapatkan varietas unggul. Sejak tahun 2007, Pusat Penelitian Surfaktan dan Bioenergi (SBRC)-LPPM-IPB telah melakukan eksplorasi jarak pagar dari beberapa daerah di Indonesia dan mengintroduksi jarak pagar dari luar negeri. Koleksi plasma nutfah harus dievaluasi secara tepat untuk mengetahui tingkat keragaman genetik dan potensinya untuk dikembangkan lebih lanjut. Karakter yang dievaluasi dapat berupa karakter anatomi, morfologi, kimia, biokimia, fisiologi ataupun molekuler. Penelitian ini bertujuan untuk mempelajari keragaman genetik dan tingkat kemiripan antar genotipe jarak pagar dan mendapatkan kriteria seleksi jarak pagar berdaya hasil tinggi pada jarak pagar koleksi SBRC LPPM-IPB. Penelitian ini dilaksanakan pada bulan Agustus 2009 - Juli 2010. Penelitian dilaksanakan di Kebun Percobaan IPB Leuwikopo, Bogor dan Kebun Jarak Pagar PT Indocement Tunggal Prakarsa, Tbk., Citeureup, Laboratorium Proses SBRC-LPPM-IPB dan Laboratorium Marka Molekuler dan Spectophotometry UV-Vis Departemen Agronomi dan Hortikultura, IPB Darmaga. Penelitian analisis keragaman berdasarkan karakter morfologi dan agronomi di lapangan disusun dalam Rancangan Kelompok Lengkap Teracak (RKLT) satu faktor. Faktor yang digunakan yaitu genotipe jarak pagar yang terdiri dari 13 genotipe. Percobaan diulang sebanyak 3 kali sehingga terdapat 39 satuan percobaan. Pengamatan karakter morfologi dan agronomi tanaman jarak pagar meliputi karakter batang, daun, bunga, buah dan biji jarak pagar. Penelitian analisis keragaman menggunakan marka RAPD dilakukan dengan 11 primer dari OPERON, yaitu E3, E7, E19, E20, M2, M5, M6, M8, H14, H16, dan H19. Sampel daun berasal dari 13 genotipe jarak pagar yang ada di lapangan. Metode yang digunakan untuk mengisolasi DNA adalah metode ekstraksi menggunakan Kit SIGMA yang dimodifikasi. Amplifikasi DNA dilakukan dengan PCR reagent dari Vivantis dengan modifikasi konsentrasi taq DNA polymerase 1,5 kali konsentrasi anjuran. Data dianalisis menggunakan program SAS 9, SPSS 15 dan NTSYS.....dst
Keyword: Jatropha, genetic variability analysis, heritability, correlation, selection characters, 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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