Judul: Characterization and Evaluation of Eight Foxtail Millet Genotypes (Setaria italica L. Beauv) from Exploration
Abstrak: Hotong (Setaria italica L. Beauv) ialah sumber karbohidrat yang mampu beradaptasi baik di lingkungan kering dan kurang subur. Tanaman ini memiliki kandungan protein, kalsium, dan antioksidan yang cukup tinggi dibandingkan padi dan jagung. Pemanfaatan hotong sebagai sumber pangan di Indonesia masih terbatas karena belum adanya varietas unggul hotong yang dilepas. Penelitian ini bertujuan mengetahui karakter agronomi dan karakter morfologi dari empat genotipe hotong hasil eksplorasi dan empat genotipe pembandingnya. Percobaan dilaksanakan pada bulan Februari - September 2021 di Kebun Percobaan Cikabayan Bawah IPB. Penelitian ini terdiri atas tiga percobaan, setiap percobaan disusun berdasarkan rancangan kelompok lengkap teracak (RKLT) faktor tunggal dengan delapan ulangan. Bahan penelitian yang digunakan terdiri atas empat genotipe hasil eksplorasi yaitu Hambapraing, Mauliru#2, Toraja, dan NTB-1, dan empat genotipe pembanding yaitu ICERI-5, ICERI-6, Botok-4, dan Botok-10. Berdasarkan scatter plot dan dendrogram yang dibangun, delapan genotipe yang diamati terbagi menjadi dua kelompok besar. Kelompok A terdiri dari genotipe ICERI-5, ICERI-6, dan Toraja dengan produktivitas yang rendah dan umur panen yang singkat. Kelompok B terdiri dari genotipe Mauliru#2, Hambapraing, NTB-1, Botok-4, dan Botok-10 dengan produktivitas yang tinggi dan umur panen yang cukup lama., Foxtail millet (Setaria italica L. Beauv) is a source of carbohydrates that adapt well in dry and less fertile environments. Foxtail millet contains higher protein, calcium, and antioxidants compared to rice and corn. The utilization of foxtail millet in Indonesia as food is still limited and there is no superior variety of foxtail millet has been released in the country. The objective of this study was to characterize foxtail millet genotypes collected from exploration. The study was conducted from February - September 2021 at the Cikabayan Experimental Field, IPB University. The study consisted of three experiments, each experiment was arranged in a randomized complete block design (RCBD) with eight replications. Foxtail millet genotypes used in this study were four genotypes collected from exploration activity namely Hambapraing, Mauliru#2, Toraja, and NTB-1, and four check genotypes namely ICERI-5, ICERI-6, Botok-4, and Botok-10. Based on the constructed scatter plot and dendrogram, the eight observed genotypes were divided into two large groups. Group A consists of the genotypes ICERI-5, ICERI6, and Toraja with low productivity and early maturity. Group B consists of genotypes Mauliru #2, Hambapraing, NTB-1, Botok-4, and Botok-10 with high productivity and late maturity.
Keyword: cereals, characterization, diversity, exploration, productivity

Judul: Pengaruh Metode Tanam terhadap Pertumbuhan dan Produktivitas Empat Genotipe Hotong (Setaria italica L.)
Abstrak: Hotong merupakan komoditas pangan yang dapat dikembangkan menjadi sumber pangan alternatif. Pengembangan sumber pangan alternatif dan perakitan varietas unggul perlu disertai dengan pengembangan paket budidaya. Tujuan penelitian ini adalah mempelajari pengaruh metode tanam terhadap pertumbuhan dan produktivitas genotipe hotong ICERI-5, ICERI-6, Botok-4, dan Botok-10. Penelitian dilaksanakan di Kebun Percobaan Cikabayan Bawah (± 240 m dpl), dan Laboratorium Pasca Panen pada bulan Oktober 2021-Mei 2022. Penelitian disusun berdasarkan rancangan petak terbagi (split-plot design) dengan petak utama yang disusun dalam rancangan kelompok lengkap teracak (RKLT). Faktor pertama dalam percobaan ini adalah metode tanam (direct seeding, transplanting M3 dan M5), sedangkan faktor kedua adalah genotipe yang terdiri atas empat genotipe. Genotipe Botok-4 dan Botok-10 memiliki habitus tanaman yang lebih tinggi, umur berbunga dan umur panen yang lebih lama, serta hasil (bobot malai utama, bobot malai per tanaman, dan bobot biji malai utama) yang lebih tinggi dibandingkan genotipe ICERI-5 dan ICERI-6. Berdasarkan umur berbunga, umur panen dan bobot biji per tanaman, metode tanam langsung (direct seeding) sesuai untuk genotipe Botok-4 dan Botok-10, sedangkan ketiga metode pindah tanam dapat digunakan untuk genotipe ICERI- 5 dan ICERI-6., Foxtail millet is an alternative crop for carbohydrate source with a low glycemic index and relative tolerance to abiotic stresses. The development of high-yielding varieties needs to be accompanied by the development of good cultivation packages. The purpose of this study was to observe the effect of the planting methods on the growth and productivity of the ICERI-5, ICERI-6, Botok-4, and Botok-10 foxtail millet genotypes. The research was carried out at the Cikabayan Experimental Field (± 240 m asl), and the Post-Harvest Laboratory from October 2021-May 2022. The experiment was arranged based on a split-plot RCBD design. The main plot was the planting method (direct seeding and transplanting M3 and M5), while the subplot was the genotype which consisted of four genotypes. The Botok-4 and Botok-10 genotypes had higher plant habitus, longer flowering and harvesting times, and higher yields (main panicle weight, panicle weight per plant, and main panicle seed weight) compared to the ICERI-5 and ICERI-6 genotypes. Based on flowering time, harvesting time, and seed weight per plant, the direct seeding method is suitable for the Botok-4 and Botok-10 genotypes, while the three transplanting methods can be used for the ICERI-5 and ICERI-6 genotypes.
Keyword: Budidaya, Genotipe, Hotong, Metode tanam, Pangan alternatif

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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