Judul: Effect of Soil P and K Content on the Growth and Yield of Tomato (Lycopersicon esculentum) in Garut Andisols.
Abstrak: Tomat merupakan komoditas hortikultura yang banyak dibudidayakan dan dimanfaatkan di Indonesia. Produktivitas tomat dapat ditingkatkan dengan pendekatan teknologi budidaya seperti menggunakan teknologi irigasi dan pemupukan yang presisi. Penelitian ini menggunakan rancangan kelompok lengkap teracak (RKLT) dengan satu faktor berupa taraf status hara P dan K (rendah, sedang, dan tinggi) menggunakan perangkat uji tanah kering (PUTK). Analisis taraf hara P dan K pada tanah Andisol menggunakan PUTK terhadap tanaman tomat dapat digunakan. Hasil pada penentuan taraf hara P berbeda nyata pada hasil bobot kering tajuk, bobot kering total, jumlah buah total, dan bobot buah total. Taraf hara P tinggi menunjukkan rataan hasil produktivitas yang paling tinggi yaitu 307,59 gram/tanaman. Hasil pada penentuan taraf hara K menunjukkan perbedaan sangat nyata pada jumlah buah total dan berbeda nyata pada bobot kering tajuk, bobot kering total, dan bobot buah total. Taraf hara K tinggi menunjukkan rataan hasil produktivitas yang paling tinggi dari semua perlakuan yaitu 320,17 gram/tanaman., Tomato is a horticultural commodity that is widely cultivated and used in Indonesia. Tomato productivity can be increased by using cultivation technology approaches such as using irrigation technology and precise fertilization. This study used a completely randomized block design (RKLT) with one factor of P and K nutrient status levels (low, medium, and high) from the results of Garut Andisol soil testing using a perangkat uji tanah kering (PUTK). Analysis of P and K nutrient levels in Andisol soil using PUTK for tomato plants can be used. The results for determining the levels of P nutrients were significantly different in the results of shoot dry weight, total dry weight, total fruit number, and total fruit weight. The high level of P nutrient indicates the highest average yield of productivity, that is 307.59 gram/plant. The results for determining the K nutrient levels showed highly significant differences in the total fruit number and significantly different in shoot dry weight, total dry weight, and total fruit weight. The high K nutrient level showed the highest average yield of all treatments, that is 320.17 grams/plant.
Keyword: PUTK, Taraf Hara, Generatif, Vegetatif

Judul: Yield Potential Test of Tomato (Solanum lycopersicum L.) Collection of PKHT IPB at Leuwikopo
Abstrak: Pengembangan varietas tomat di dataran rendah dapat menambah luas penanaman tomat, dan mengurangi tekanan penanaman di dataran tinggi yang berpotensi merusak kelestarian lingkungan. Varietas tomat dataran rendah yang unggul dapat meningkatkan produksi sehingga kebutuhan konsumsi tomat dapat tercukupi. Uji daya hasil dibutuhkan untuk menguji daya hasil galur-galur tomat yang telah ada, kemudian diseleksi untuk dikembangkan menjad varietas. Penelitian ini bertujuan untuk mendapat daya hasil genotipe tomat koleksi PKHT IPB. Penelitian dilakukan di Kebun Percobaan Leuwikopo, IPB, Dramaga, Bogor pada bulan April hingga Agustus 2013. Metode penelitian menggunakan Rancangan Kelompok Lengkap Teracak (RKLT), satu faktor dengan tiga ulangan. Faktor tersebut adalah 11 galur potensial tomat yang terdiri atas 3 varietas komersial (Intan, Ratna, dan Karina) sebagai pembanding.Genotipe yang diuji menujukkan keragaman sangat nyata untuk karakter bobot per buah, tinggi tanaman, lebar daun, jumlah buah per tanaman, panjang buah, dan diameter buah, serta nyata untuk karakter tebal daging, panjang daun dan umur berbunga. Tidak terdapat perbedaan pada karakter diameter batang, umur panen, bobot buah pertanaman dan produktivitas. Karakter bobot perbuah genotipe IPBT8, IPBT43, IPBT57, IPBT60, IPBT64 dan IPBT78 tidak berbeda dengan varietas pembanding. Karakter jumlah buah pertanaman genotipe IPBT3, IPBT30, IPBT33, dan IPBT53 menunjukkan jumlah lebih banyak dibandingkan varietas pembanding. Genotipe tomat yang memiliki daya hasil lebih baik dari genotipe lainnya adalah genotipe IPBT8., The development of tomato varieties in the lower elevation lands is important for increasing the area of planting tomatoes, and reduce the pressure of planting in the highlands that have the potential to damage environmental sustainability. The superior low land tomato varieties can increase production so that tomato consumption needs can be fulfilled. The trial results are needed to identify the potential of the existing tomato genotype. This research aimed to obtain the information of the tomato genotype collection of PKHT-IPB. The experiment was conducted at Leuwikopo Field Station, IPB, Dramaga, Bogor from April to August 2013. The genotype was arranged in Randomized Complete Block Design (RCBD), with three replications. The tomato genotypes that used in this experiment consist of 11 potential genotypes and 3 commercial varieties (Intan, Ratna, and Karina) as control varieties. The tested genotypes showed very significantly differences for the character of fresh weight per fruit, plant height, leaf width, fruit number per plant, fruit length, and fruit diameter, and significantly differences for the character of fruit flesh thickness, leaf length, and flowering time. There were no differences on the character of stem diameter, harvesting time, fresh weight per plant and productivity.The character of fresh weight per fruit of IPBT8, IPBT43, IPBT57, IPBT60, IPBT64 and IPBT78 similar to the control varieties. The character of fruit number per plant of IPBT3, IPBT30, IPBT33, and IPBT53 show more number than the control varieties. Tomato genotypes that have a better yield ability than other genotypes were IPBT8.
Keyword: productivity, IPBT8, Lower elevation lands

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.
Keyword: