Judul: Perbaikan Keragaan Bibit Jeruk Pamelo (Citrus maxima (Burm) Merr) Melalui Aplikasi Strangulasi.
Abstrak: Penelitian bertujuan mempelajari pengaruh strangulasi tunggal dan ganda terhadap keragaan bibit jeruk besar (Citrus maxima (Burm) Merr). Penelitian ini dilaksanakan pada bulan November 2011 sampai dengan Februari 2012 bertempat di Rumah Kaca Kebun Percobaan Cikabayan, Dramaga, Institut Pertanian Bogor. Percobaan menggunakan Rancangan Acak Lengkap (RAL) dengan satu faktor yang dicobakan yaitu perlakuan strangulasi yang terdiri dari empat taraf yaitu tanpa strangulasi (T0), strangulasi tunggal dengan ketinggian 5 cm dari okulasi (T1), strangulasi ganda dengan ketinggian 5 cm dari okulasi dan jarak antar kawat 5 cm (T2), 10 cm (T3), dan 15 cm (T4). Setiap perlakuan diulang sebanyak 8 kali dengan menggunakan 1 tanaman untuk setiap ulangan sehingga terdapat 40 satuan percobaan. Tanaman yang digunakan dalam penelitian kali ini adalah bibit jeruk pamelo Citrus maxima (Burm) Merr kultivar Nambangan hasil okulasi dengan batang bawah Javance citrun. Bibit telah berumur 14 bulan setelah okulasi atau 25 MSS (Minggu Setelah Strangulasi). Perlakuan strangulasi dilakukan di batang utama yaitu 5 cm di atas sambungan. Strangulasi dilakukan menggunakan kawat berdiameter 1 mm. Pengikatan kawat pada perlakuan strangulasi ganda dilakukan dua kali dengan jarak berbeda yaitu 5 cm, 10 cm dan 15 cm. Aplikasi strangulasi telah dilakukan pada umur 8 bulan setelah okulasi. Pengamatan vegetatif tanaman dilakukan tiap dua minggu sekali. Pemeliharaan tanaman yang dilakukan adalah penyiraman, pemupukan dengan pupuk NPK dan ZA, dan pengendalian OPT secara manual dan kimia. Perlakuan strangulasi dapat memperbaiki keragaan pada bibit jeruk pamelo varietas Nambangan. Perlakuan strangulasi menghasilkan cabang lebih banyak daripada perlakuan tanpa strangulasi. Perlakuan strangulasi gandamemberikan pengaruh peningkatan jumlah cabang lebih banyak daripada perlakuan strangulasi tunggal. Perlakuan strangulasi ganda jarak 15 cm memiliki pengaruh terbaik dibanding perlakuan strangulasi lainnya.
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Judul: Pengaruh Strangulasi Single dan Double terhadap Perbaikan Keragaan Bibit Jeruk Pamelo (Citrus grandis (L.) Osbeck).
Abstrak: The purpose of this research was to study the influence of single and double strangulation for stimulated vegetatif growth in order to improved canopy architecture of young pummelo seedling (Citrus grandis (L.) Osbeck). This research was conducted from March to September 2011 in green house of Cikabayan Experimental Station IPB, Darmaga. Biochemical analysis was done in Laboratory of Balai Penelitian Tanaman Obat dan Aromatik, Bogor and Post- Harvest Laboratory, IPB. The experiment was conducted in Completely Randomized Block Design one factor consist of 5 treatment there were control (T0), single strangulation (T1), double strangulation with distance between wire:5 cm (T2), 10 cm (T3) and 15 cm (T4). The experiment consisted of 5 replicates then there were 25 experimental units. Each experimental unit contained 2 plants and total crop are 50 plants. Strangulation treatment was done in May 19th and wires removed in August 10th 2011. The result of this research showed that single and double strangulation had significant response increase vegetatif growth to the numbers of scion diameter, numbers of leaf, volume of canopies, numbers of branch, total strarch in leaf than control. Double strangulation with distance between 2 wires 15 cm (T4) was the highest number of branch (5 branch), number of leaf (87.4 leaves) and had significant response increase starch of leaf.
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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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