Judul: The use of Ecoenzyme and Liquid Organic Fertilizer in Potato (Solanum tuberosum L.) IPB CP3
Abstrak: Kentang IPB CP3 merupakan salah satu varietas yang dikembangkan IPB untuk industri keripik kentang. Ketersediaan benih berkualitas penting untuk meningkatkan produksi kentang. Salah satu faktor penentu adalah pemberian pupuk. Penelitian ini menganalisis pengaruh ekoenzim dan pupuk organik cair (POC) terhadap pertumbuhan dan produksi umbi kentang IPB CP3 generasi ke-0 (G0). Penelitian dilakukan di rumah kaca yang berlokasi di Desa Kayu Ambon, Lembang, Kabupaten Bandung Barat. Penelitian ini menggunakan faktor perlakuan pupuk yaitu ekoenzim dan POC Magnon yang dirancang secara acak lengkap dengan sembilan ulangan. Tanaman ditanam pada polybag yang berisi media cocopeat. Hasil percobaan menunjukkan perlakuan ekoenzim dan POC Magnon dapat meningkatkan bobot basah, bobot kering, laju pertumbuhan, bobot umbi kecuali tinggi tanaman dan jumlah umbi. Konsentrasi ekoenzim dan POC perlu ditingkatkan untuk memaksimalkan pertumbuhan dan produksi umbi.
Keyword: IPB CP3 potato,, seed., ecoenzyme, POC

Judul: Growth and Production of G0 Potato (Solanum tuberosum L.) Seed Tuber of IPB CP3 in Greenhouse and Screenhouse in the Medium Altitude
Abstrak: Kentang (Solanum tuberosum L.) adalah komoditas hortikultura yang memiliki nilai ekonomi tinggi. Indonesia masih mengimpor benih kentang karena produksi benih dalam negeri tidak mencukupi. Keterbatasan produksi benih kentang industri, salah satunya kentang varietas IPB CP3 disebabkan oleh keterbatasan luas lahan di dataran tinggi. Untuk meningkatkan produksi benih, perlu dilakukan pemanfaatan lahan di dataran menengah dengan menggunakan varietas yang sesuai. Penelitian ini bertujuan membandingkan pertumbuhan dan produksi benih umbi G0 kentang varietas IPB CP3 dari stek yang ditanam di dalam rumah kaca dan rumah kasa di dataran menengah. Stek pucuk berumur 2 minggu setelah tanam yang sudah berakar ditanam pada polybag yang berisi media cocopeat. Setiap satuan percobaan terdiri atas 20 tanaman dengan 3 ulangan, sehingga di dalam rumah kaca atau rumah kasa terdapat 60 tanaman. Panen dilakukan pada umur 90 hari setelah tanam. Parameter yang diamati adalah tinggi tanaman, jumlah buku, jumlah daun, jumlah umbi, bobot basah serta bobot kering tajuk dan umbi. Hasil penelitian menunjukkan bahwa rumah kaca dan rumah kasa memberikan pengaruh yang signifikan terhadap pertumbuhan dan produksi benih umbi G0 kentang IPB CP3. Pertumbuhan tanaman dan produksi benih umbi G0 kentang varietas IPB CP3 di dalam rumah kasa secara signifikan lebih baik daripada rumah kaca., Potato (Solanum tuberosum L.) is a horticultural commodity with high economic value. Indonesia is still importing potato seeds due to insufficient seed production. The lack of seed tuber production for potato chips is due to the limited land area in high-altitude regions. It is necessary to produce seed tubers in the medium altitude with suitable varieties. The study aims to compare the growth and production of G0 potato seed tubers of IPB CP3 variety planted in greenhouse and screenhouse in the medium altitude. Two weeks old of the rooted shoot-cuttings were transferred into polybags containing cocopeat media. Each experimental unit consists of 20 plants with 3 replications, therefore there are 60 plants in greenhouse and screenhouse. The potato seed tubers were harvested at 90 days after planting. The parameters observed were plant height, number of nodes, number of leaves, number of tubers, fresh and dry weight of the plant shoot and tubers. The research showed that greenhouse and screenhouse had a significant effect on the growth and production of G0 potato seed tubers of IPB CP3. The growth and production of G0 potato seed tubers of the IPB CP3 variety in screenhouse is significantly better than that in greenhouse.
Keyword: greenhouse, potato chips, screenhouse, shoot-cuttings, sipitri

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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