Judul: Preliminary Yield Evaluation of Maize Hybrids in  Gowa, South Sulawesi
Abstrak: Varietas jagung hibrida saat ini lebih banyak dibudidayakan di Indonesia dibandingkan varietas jagung bersari bebas. Perbaikan hasil panen dapat dilakukan melalui pemuliaan tanaman. Penelitian ini bertujuan mengevaluasi daya hasil sejumlah hibrida jagung berdasarkan karakter agronomi dan mengidentifikasi hibrida yang memiliki potensi hasil yang tinggi. Penelitian dilaksanakan di Kebun Percobaan Balai Penelitian Tanaman Serealia, Kecamatan Bajeng, Kabupaten Gowa, Sulawesi Selatan, mulai Februari 2022 hingga Mei 2022. Rancangan yang digunakan yaitu rancangan kelompok tak lengkap (RKTL) dengan tiga ulangan dan tiga kelompok dalam ulangan. Terdapat 56 hibrida uji yang terdiri atas 44 hibrida hasil persilangan line x tester dari Balitsereal dan 12 hibrida IPB. Empat varietas hibrida komersial digunakan sebagai pembanding. Hasil penelitian menunjukkan adanya keragaman antar genotipe pada semua karakter pengamatan. Hibrida HERC 25 (ERC 7 x N79) memiliki rata-rata potensi hasil tertinggi, nyata lebih tinggi dari Pertiwi 5 dan NASA 29, namun tidak berbeda nyata dengan BISI 18 dan P27. Nilai daya gabung umum tertinggi hasil pipilan kering ditemukan pada line ERC 7 dan tester P2, sedangkan nilai daya gabung khusus tertinggi dimiliki oleh kombinasi ERC 5 x N79. Tinggi tanaman, panjang tongkol, jumlah biji per baris, bobot 1000 biji, dan rendemen hasil berkorelasi positif sangat nyata terhadap hasil pipilan kering. Hibrida-hibrida potensial dapat diuji dalam penelitian selanjutnya.
Keyword: daya gabung, evaluasi hibrida, line x tester

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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