Judul: Hama dan penyakit tanaman terung (Solanum melongena L.) di Kecamatan Rancabungur, Kabupaten Bogor
Abstrak: Eggplant (Solanum melongena L.) is a vegetable crop that quite common cultivated in Indonesia. The consumption level of eggplant increases from year to year. There are few information on pests and diseases of the crop in Indonesia. However, pests and diseases become potentially problem in the future when the crop is grown widely. The objective of this research was to obtain information about pest and disease occurrences found in eggplant growing area in Rancabungur their population or damage level. The research method included observation, sampling of the pests and diseases at two eggplant areas, and laboratory identification of the causal agents. The eggplant vegetative and generative growth phases were observed in the same area and period of time. There are some pests found predominantly in eggplant at high population i.e. Empoasca sp. (Hemiptera: Cicadellidae) and Epilachna sp. (Coleoptera: Coccinellidae), whereas Valanga sp. (Orthophtera: Acrididae) (low population), Acherontia sp. (Lepidoptera: Sphingidae), Bactrocera spp. (Diptera: Tephritidae), Mictis longicornis (Hemiptera: Coreidae), and Aulacophora sp. (Coleoptera: Chrysomelidae) were at low population. Eggplant’s diseases found at high incidence in the area were fruit rot (Phomopsis sp.) and anthracnose (Colletotrichum sp.), whereas leaf spot (Alternaria sp.) and bacterial wilt (Ralstonia solanacearum) were at low incidence. All of those pests and diseases, except Bactrocera spp., caterpillar, fruit rot, and anthracnose found at both growth phase of the plant. Fruit rot, and anthracnose were the most important diseases of eggplant at generative phase with the intensity about 47.09% and 40.84%.
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Judul: Deteksi Cendawan yang Terbawa Benih Terung (Solanum melongena)
Abstrak: Kesehatan benih terung ungu (Solanum melongena) di Indonesia masih jarang diteliti. Kualitas terung dapat ditentukan melalui uji kesehatan benih. Oleh karena itu, penelitian ini bertujuan mendeteksi dan mengidentifikasi cendawan yang terbawa pada benih terung. Sampel yang digunakan ialah benih petani dari Kecamatan Tenjolaya, Bogor dan benih komersial. Deteksi cendawan pada benih dilakukan dengan uji kertas merang selama satu minggu. Benih terung yang berasal dari petani menunjukkan terdapatnya cendawan sebanyak 20% pada benih yang berkecambah hidup dan 3% berkecambah mati, sedangkan benih terung komersial menunjukkan terdapatnya cendawan sebanyak 11% pada benih yang berkecambah hidup dan 1% berkecambah mati. Cendawan dari benih diisolasi menggunakan teknik spora tunggal. Isolat cendawan yang berhasil diidentifikasi ialah Fusarium decemcellulare, F. solani, Fusarium spp., Memnoniella sp., Rhizoctonia sp., dan 11 cendawan Mycelia Sterilia yang belum dapat ditentukan genusnya.
Keyword: Bogor Agricultural University, Institut Pertanian Bogor, IPB, Eggplant, Isolation fungi from seeds, Straw paper test

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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