Judul: Pengaruh Zat Pengatur Tumbuh NAA dan IBA terhadap Pembentukan Akar dan Tunas Stek Jeruk Pamelo (Citrus grandis (L.) Osbeck).
Abstrak: The objective of this research was to study the effect of application of NAA and IBA on pummelo stem cuttings. This research was arranged in split plot design with two factors and five replications. The type of auxin (NAA and IBA) as the main plot. The concentration of auxin (0 ppm, 100 ppm, 150 ppm, 200 ppm, and 250 ppm) as the subplot. The result showed that the type of auxin was affected on rooting percentage, but did not affected on the other parameters. The type of auxin IBA had greater rooting percentage than NAA on pummelo cuttings. The auxin concentration had significant effect on the percentage of callusing, rooting, sprouting, and rooting-sprouting. The auxin concentration also affected on root length, root diameter, shoot length, and shoot diameter, but did not affected on roots and shoots number. The result showed that the auxin concentration 200 ppm with soaking method was the best concentration on root and shoot formation in pummelo cuttings.
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Judul: Pengaruh konsentrasi zat pengatur tumbuh dan panjang stek terhadap pembentukan akar dan tunas pada stek apokad (Persea americana Mill.)
Abstrak: Penelitian ini bertujuan untuk mengetahui konsentrasi zat pengatur tumbuh (ZPT) dan panjang stek yang sesuai terhadap kemampuan berakar dan bertunas pada stek ranting tanaman apokad (Persea americana Mill.). Penelitian dilaksanakan dari bulan Desember 2007 sampai dengan bulan Mei 2008. Penelitian tahap pertama Pengaruh Konsentrasi NAA (dalam Rootone- F) dan Panjang Stek Terhadap Pembentukan Akar dan Tunas pada Stek Apokad (Persea americana Mill.) dengan Menggunakan Metode Perendaman dilakukan di gedung Fakultas Pertanian IPB Darmaga, Bogor. Penelitian tahap kedua Penentuan Konsentrasi IAA yang Sesuai pada Penyetekan Tanaman Apokad (Persea americana Mill.) dengan Menggunakan Metode Celup Cepat dilakukan di gedung Fakultas Pertanian IPB Darmaga dan greenhouse Pusat Kajian Buah Tropika (PKBT) Baranang Siang, Bogor.
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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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