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: Agronomic Performance and Yield Potential of 30 Maize Hybrids under Biotic Stress Conditions
Abstrak: Jagung adalah komoditas yang memiliki nilai ekonomis dengan permintaan meningkat setiap tahunnya sehingga perlu dilakukan peningkatan potensi hasil. Banyak faktor yang mempengaruhi potensi hasil jagung sehingga perlu dilakukan pengujian terhadap calon varietas baru. Penelitian ini bertujuan mengevaluasi keragaan agronomi dan potensi hasil 30 hibrida jagung. Penelitian dilaksanakan di Grujukan, Puger Kulon, Jember mulai dari bulan September 2020 hingga Januari 2021. Rancangan percobaan yang digunakan yaitu rancangan kelompok lengkap teracak dengan tiga ulangan. Terdapat 32 genotipe yang diuji yaitu 30 genotipe berasal dari persilangan antara galur IPB dengan galur koleksi Balitsereal dan dua varietas pembanding (BISI 2 dan NK6172). Hasil penelitian menunjukkan bahwa terdapat keragaman antar genotipe pada karakter daya tumbuh, umur berbunga jantan, tinggi tanaman, tinggi tongkol utama, diameter batang, diameter tongkol, jumlah baris biji, jumlah biji dalam baris, bobot tongkol, bobot biji per tongkol, bobot seribu biji, kadar air, dan rendemen hasil. Genotipe juga berpengaruh nyata terhadap ketahanan terhadap serangan ulat dan bulai. Terdapat sepuluh genotipe uji yang memiliki potensi hasil setara dengan kedua varietas pembanding, dan yang terbaik diantaranya yaitu P13xNei., Maize is a commodity having a high economic value with increasing demand over years, and therefore it is necessary to increase its production. Several factors affected maize yield, so it is important to evaluate the prospective of new varieties. This research aimed to evaluate the agronomic performance and yield potential of 30 maize hybrids. The research was conducted at Grujukan, Puger Kulon, Jember from September 2020 to January 2021. The experimental design was a randomized complete block design with three replications. Thirty two maize hybrids, consisting of 30 hybrids of IPB lines x ICERI lines, and two commercial hybrid varieties as checks (BISI 2 and NK6172), were evaluated. The results indicated variations among genotypes for character of growth percentage, days to anthesis, plant height, main ear height, stem diameter, ear diameter, number of grain rows per ear, number of grain in rows, ear weight, grain weight per ear, 1000 grain weight, grain moisture, and yield percentage. In addition, the genotype also had significant effects on fall armyworm and downy mildew resistance. Ten test hybrids had a comparable yield potential with the two check varieties, and the best among which was P13xNei.
Keyword: hybrid evaluation, maize breeding

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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