Judul: Impact Of Eggplant Hybrid Seed Adoption To Local Germplasm Diversity And Farmer’s Income, The Case Study In North-Part Of West Java).
Abstrak: Eggplant is one of the most importance vegetable crops in Indonesia with high diversity either in fruit shape, size, color, and other plant characters. Hybrid seed is one way to increase the productivity to fulfill the need of fresh product with the chances of increasing or decreasing of diversity in Indonesia. This study was conducted in Karawang, Indramayu and Cirebon with the purposes: analyze the impact of the hybrid seed adoption to the local germplasm; analyze factors influenced the adoption of hybrid; and analyze the economic benefit of hybrid seeds to the farmer’s income. Identification and characterization of germplasm collected before and after year 2000 conducted at the research farm of PT East West Seed Indonesia and farmer’s field. The germplasm diversity in Indramayu and Cirebon are decreasing, while in Karawang is increasing as the impact of using hybrids seeds with the coming out of color and shape variation. The local germplasm of round eggplant is available. Brand image (X8), high selling price of fresh product (X10), the easiness of the fresh product to be sold (X11) and diseases resistant (X13) are the factors influenced the adoption of eggplant hybrid seeds, with the logit function Y = -1.329 + 2.863X8 – 5.159 X10 + 3.049 X11 + 3.026 X13. Market share of hybrid seeds around 80% on the periods 2004-2011, dominated by hybrids long eggplant type, and 16% of the total local germplasm (20%) dominated by round type. Hybrid seed increase the farmer’s income 2.16 times comparing to the using of local germplasm, with 3.85 of R value on partial budget analysis and 113.9 of Quality Seed Multiplier value.
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Judul: Growth and Yield of Several Eggplant Varieties (Solanum melongena L.) in Plastic House
Abstrak: Terung merupakan salah satu komoditas sayuran yang banyak diminati masyarakat. Produktivitas terung nasional juga terus mengalami peningkatan dari tahun ke tahun. Penggunaan varietas unggul merupakan salah satu upaya dalam menjaga kestabilan produksi terung. Penelitian ini bertujuan mengetahui penampilan karakter pertumbuhan dan hasil beberapa varietas terung di rumah plastik. Penelitian dilakukan di rumah plastik Kebun Percobaan Cikabayan, Institut Pertanian Bogor selama bulan Juli hingga November 2023. Penelitian ini menggunakan rancangan kelompok lengkap teracak (RKLT) dengan menggunakan 6 varietas (Hitavi, Garnet, Provita, Mustang, Laguna, dan Torino) dan terdiri atas 4 ulangan. Penggunaan beberapa varietas unggul menunjukkan keragaman pada hasil pengamatan vegetatif dan generatif. Keragaman tersebut terdapat pada karakter diameter batang, panjang daun, lebar daun, dan rata-rata bobot per buah. Diameter batang berkisar antara 2,07 cm (Provita) hingga 2,84 cm (Torino). Panjang daun berkisar antara 42,73 cm (Provita) hingga 52,78 cm (Laguna). Lebar daun berkisar antara 31,48 cm (Provita) hingga 41,45 cm (Torino). Bobot per buah berkisar antara 41,13 g/buah (Provita) hingga 96,75 g/buah (Laguna). Produktivitas tanaman berkisar antara 0,96 kg/tanaman (Provita) hingga 2,53 kg/tanaman (Laguna). Pertumbuhan dan hasil panen yang tidak optimal disebabkan oleh suhu tinggi, serangan hama kutu putih serta tungau merah pada tanaman., Eggplant is a vegetable crop in great demand. National eggplant productivity continues to increase from year to year. The use of superior varieties is needed to maintain the stability of eggplant production. This research aims to determine the growth characteristics and yields of several eggplant varieties in the plastic house. The research was conducted in the plastic house of the Cikabayan Experimental Station, Bogor Agricultural University from July to November 2023. It used a randomized complete block design using 6 varieties (Hitavi, Garnet, Provita, Mustang, Laguna, and Torino) and replicated 4 times. The use of several superior varieties showed variability in vegetative and generative characters. The variability was found in the characters of stem diameter, leaf length, leaf width, and average weight per fruit. Stem diameters ranged from 2.07 cm (Provita) to 2.84 cm (Torino). Leaf length ranged from 42.73 cm (Provita) to 52.78 cm (Laguna). Leaf width ranged from 31.48 cm (Provita) to 41.45 cm (Torino). The weight per fruit ranged from 41.13 g/fruit (Provita) to 96.75 g/fruit (Laguna). Plant productivity ranged from 0.96 kg/plant (Provita) to 2.53 kg/plant (Laguna). Suboptimal growth and crop yields were caused by high temperatures and attacks of mealybugs and red mites on plants, so the cultivation environmental conditions and selection of superior varieties need to be considered in order to obtain optimal yields
Keyword: Characterization, eggplant, plastic house, varieties

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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