Judul: Evaluation of Agronomic Traits and Yield Potential of Maize Genotypes (Zea mays L.) in Sumenep, East Java
Abstrak: Maize is the second main food crop after rice grown by farmers in Indonesia. Maize production is currently used for food, feed, and industry. Nusa Tenggara and Madura are areas that use maize as the main source of carbohydrates. Due to high demand over years, superior maize varieties with high yield potential are needed. This study aimed to identify maize genotypes with good agronomic performance and high yield potential. The experiment was conducted at the Batang-Batang Laok Village, Batang-Batang District, Sumenep Regency, East Java from October 2020 to March 2021. The genotypes evaluated consisted of 23 F1 hybrids, four single cross hybrid varieties, two three-way cross hybrid varieties, two open-pollinated varieties, and three local varieties. The research was conducted using a single factor randomized complete block design (RCBD) with three replications. The results showed that the genotype effect was significant on germination percentage, days to anthesis and silking, anthesis silking interval, plant height, main ear height, stem diameter, fresh ear weight with husk, fresh ear weight without husk, dry ear weight without husk, days to harvest, fresh ear length, dry ear length, fresh ear diameter, dry ear diameter, number of grain rows (fresh and dry ears), number of grains per row (fresh and dry ears), ear weight, grain weight per ear, 1000-grain weight, grain moisture, and prediction of grain yield potential. Dry ear weight had a significant and positive correlation with fresh and dry ear length, dry ear diameter, and number of fresh and dry grain per row. B2 x Mr14A has a higher predicted grain yield potential than NK 6172, and is recommended for further evaluation.
Keyword: plant breeding, agronomic characters, maize hybrids, yield evaluation

Judul: Evaluation of Agronomic Traits and Yield  Potential of 60 Maize Hybrids (Zea mays L.)
Abstrak: Produksi jagung nasional di Indonesia masih perlu ditingkatkan melalui pengembangan varietas-varietas unggul hibrida untuk memenuhi kebutuhan pangan, pakan, dan industri. Hibrida yang diuji perlu dilakukan evaluasi dan dibandingkan dengan varietas pembanding. Penelitian ini bertujuan mengevaluasi keragaan agronomi dan potensi hasil pada 60 hibrida uji hasil program pemuliaan IPB. Penelitian dilaksanakan pada November 2022 hingga Maret 2023 di Kebun Percobaan Leuwikopo, Bogor. Penelitian ini menggunakan rancangan augmented kelompok lengkap teracak dengan 60 genotipe dan 3 kelompok. Genotipe yang diuji meliputi 6 pembanding, yaitu BISI 18, JHG02, P21, P27, NK Perkasa, dan NK Sumo dengan tiga ulangan, serta 60 hibrida uji tanpa ulangan. Terdapat keragaman genotipe uji jagung pada seluruh peubah pengamatan, kecuali umur berbunga jantan, umur berbunga betina, umur panen, dan jumlah tongkol per tanaman. Semua peubah kuantitatif yang diamati memiliki nilai heritabilitas arti luas yang tinggi, kecuali umur berbunga jantan dan jumlah tongkol per tanaman. Hibrida uji yang potensial adalah H1 x L27, P42 x L23, L15 x L53, L68A x H1, MR14 x B1, P42 x L27, L15 x B4B, B4 x L23, B4 x B1, Nei x P2, P10 x L152, P42 x P10, L15 x Nei, dan L68B x B4B. Produksi hibrida uji tertinggi P42 x L23, National production of maize in Indonesia needs to be increased through the development of superior hybrid maize varieties for food, feed, and industries. The hybrid candidates need to be evaluated and compared with the check varieties. This research aimed to evaluate the agronomic performance and yield potential of 60 maize hybrids from the IPB University breeding program. This research was conducted from November 2022 to March 2023 at the Leuwikopo Experimental Station, Bogor. This study used an augmented randomized complete block design with 60 genotypes and 3 blocks. The genotypes include 6 check varieties, namely BISI 18, JHG02, P21, P27, NK Perkasa, and NK Sumo with three replications, and 60 test hybrids without replication. The genotype effect was significant for all traits observed except for days to tasseling, days to silking, days to harvest, and number of ears per plant. All observed quantitative traits have a high broad-sense heritability estimate except days to taselling and number of ears per plant. The potential hybrid candidates are H1 x L27, P42 x L23, L15 x L53, L68A x H1, MR14 x B1, P42 x L27, L15 x B4B, B4 x L23, B4 x B1, Nei x P2, P10 x L152, P42 x P10, L15 x Nei, dan L68B x B4B. The test hybrid having the highest yield was P42 x L23.
Keyword: evaluation, hybrid, maize breeding, yield

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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