Judul: Yield Trial of 38 New Plant Type Rice in Low Dose Fertilization
Abstrak: Padi merupakan tanaman pangan yang digunakan sebagai pemenuhan kebutuhan karbohidrat utama masyarakat Indonesia. Peningkatan produktivitas padi diperlukan melalui pemuliaan tanaman padi tipe baru untuk memenuhi kebutuhan padi nasional. Penelitian ini bertujuan menguji galur-galur padi sawah tipe baru pada kondisi pemupukan dosis rendah. Penelitian dilaksanakan di Kebun Percobaan IPB Sawah Baru Desa Babakan, Kecamatan Dramaga, Kabupaten Bogor, Jawa Barat sejak Bulan April sampai Juli 2021. Penelitian menggunakan rancangan kelompok lengkap teracak (RKLT) faktor tunggal yaitu terdiri atas 38 galur dan satu varietas pembanding dengan dua ulangan. Hasil analisis ragam pada galur-galur uji memiliki daya hasil yang tidak berbeda nyata dengan varietas pembanding. Namun, terdapat 3 nomor galur yang memiliki daya hasil lebih tinggi serta memiliki karakter agronomi yang lebih baik daripada varietas Ciherang. Galur-galur tersebut adalah IPB187-F-37-1-2 (6,26 ton ha-1), IPB193-F30-2 (6,22 ton ha-1) dan IPB189-F-132-1-1 (6,20 ton ha-1), sedangkan varietas Ciherang sebagai pembanding memiliki daya hasil sebesar 5,87 ton ha-1., Rice is a food crop that is used to fulfill the main carbohydrate needs of the Indonesian people. Increasing rice productivity is needed through breeding of new types of rice plants to meet the national rice needs. This study aimed to evaluate promising lines of rice under low-dose fertilization conditions. The experiment was conducted at the Sawah Baru Experimental Station IPB, Babakan Village, Dramaga, Bogor, West Java, started from April to July 2021. The study used of randomized complete block design (RCBD) single factor consisting of 38 lines and one check variety with two replications. The results showed that yield of the lines evaluated were no significantly different from the check varieties. However, there were 3 lines that had the higher yield and had better agronomic characters than the Ciherang variety. These lines are IPB187-F-37-1-2 (6.26 ton ha-1), IPB193-F-30-2 (6.22 ton ha-1) and IPB189-F-132-1-1 (6.20 ton ha-1), while the Ciherang variety check has a yield of 5.87 tons ha-1.
Keyword: agronomic character, new plant type, yield power

Judul: Preliminary Yield Trial of 84 Lowland Rice Lines (Oryza sativa L.) of F5 and F6 Generation.
Abstrak: Beras merupakan sumber karbohidrat utama masyarakat Indonesia. Peningkatan potensi produktivitas padi untuk mencukupi kebutuhan masyarakat terus dilakukan melalui perbaikan mutu dengan kegiatan pemuliaan tanaman dimana salah satu tahapannya yaitu uji daya hasil pendahuluan. Penelitian ini bertujuan menguji daya hasil dan keragaan galur harapan padi generasi F5 dan F6 untuk memperoleh galur yang memiliki daya hasil dan karakter agronomi lebih baik sebagai galur yang akan diuji pada tahapan berikutnya. Penelitian dilaksanakan pada bulan Februari hingga Juli 2023 di Kebun Percobaan Sawah Baru, Kecamatan Dramaga, Bogor dan Laboratorium Pemuliaan Tanaman. Percobaan menggunakan Rancangan Kelompok Lengkap Teracak faktor tunggal dengan 84 galur dan 2 varietas pembanding sebagai perlakuan. Hanya galur IPB200-F-42 dengan daya hasil nyata lebih tinggi daripada Inpari 32 (4,58 ton ha-1) dengan produktivitas sebesar 7,16 ton ha-1, namun tidak berbeda nyata dengan Ciherang (5,21 ton ha-1) berdasarkan analisis statistik. Meskipun demikian, terdapat galur yang cenderung memiliki produktivitas lebih tinggi daripada varietas pembanding berdasarkan nilai rataan serta memiliki karakter agronomi sesuai dengan kriteria PTB. Galur-galur tersebut yaitu IPB200-F-2, IPB200-F-14, IPB200-F-15, IPB200-F-17, IPB204-E-6, IPB200-F-21, IPB200-F-22, IPB200-F-25, IPB204-E-10, IPB201-F-16, IPB200-F-43, IPB200-F-44, IPB187-F-40-1-1., Rice is the main source of carbohydrates for Indonesian people. Increasing the potential for rice productivity to meet community needs continues to be carried out through quality improvement through plant breeding activities, where one of the stages is preliminary yield testing. This study aims to test the yield and performance of the expected lines of F5 and F6 generations of rice in order to obtain lines that have better yield and agronomic characteristics as lines to be tested in the next stage. The research was conducted from February to July 2023 at the Sawah Baru Experimental Garden, Dramaga District, Bogor, and the Plant Breeding Laboratory. The experiment used a single factor randomized block design with 84 lines and two control varieties as treatments. IPB200-F-42 is the only one line which had significantly higher yields than Inpari 32 (4.58 tons ha-1) with a productivity of 7.16 tons ha-1, but was not significantly different from Ciherang (5.21 tons ha-1) based on statistical analysis. Nonetheless, there are lines that tend to have higher productivity than the control varieties based on the average value and have agronomical characteristics according to the PTB criteria. These lines are IPB200-F-2, IPB200-F-14, IPB200-F-15, IPB200-F-17, IPB204-E-6, IPB200-F-21, IPB200-F-22, IPB200-F-25, IPB204-E-10, IPB201-F-16, IPB200-F-43, IPB200-F-44, IPB187-F-40-1-1.
Keyword: genotype, new plant type of rice, productivity, selection

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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