Judul: Performance of Characters from Local Varieties, National Varieties, and Breeding Lines of Sorghum
Abstrak: Sorgum merupakan tanaman serealia dengan daya adaptasi yang luas dan memiliki banyak manfaat. Benih unggul yang masih sulit diperoleh dan terbatas menjadi salah satu masalah dalam pengembangan sorgum di Indonesia. Terdapat beberapa jenis sorgum varietas lokal, varietas nasional, dan galur-galur hasil pemuliaan yang perlu dilakukan uji keragaan karakter agronomi, hasil, dan ketahanan penyakit untuk memperoleh varietas dan galur sorgum yang berpotensi dikembangkan dalam program pemuliaan tanaman dan dilepas sebagai varietas baru. Penelitian dilaksanakan pada bulan Februari-Juli 2021 di Kebun Percobaan Leuwikopo dan Laboratorium Pemuliaan Tanaman, Departemen Agronomi dan Hortikultura, IPB University. Rancangan percobaan yang digunakan adalah rancangan kelompok lengkap teracak satu faktor yaitu genotipe dengan tiga ulangan. Berdasarkan analisis ragam semua genotipe memiliki keragaman karakter agronomi dan hasil yang diamati, juga keragaman karakter pada keparahan penyakit kecuali karat daun saat 60 dan 70 hari setelah tanam (HST), serta busuk batang. Genotipe A-125-1-6-1-6 berpotensi dikembangkan sebagai bahan pangan dan pakan ternak. Genotipe C-375-17-1-5 berpotensi dikembangkan sebagai bahan pangan dengan tinggi tanaman sedang. Genotipe Pulut 5 berpotensi dijadikan tetua untuk menghasilkan sorgum berumur genjah. Genotipe dari galur hasil pemuliaan menunjukkan respon sangat tahan terhadap penyakit antraknosa dan karat daun, kecuali Soraya 3. Varietas lokal memiliki respon ketahanan penyakit tahan dan agak tahan., Sorghum is categorized as a cereal crop with a wide range of adaptability and numerous advantages. Superior seeds are still difficult to obtain and limited supplay is one of the challenges in Indonesia sorghum development. There are several types of sorghum local varieties, national varieties, and breeding lines that need to be tested for the performance of agronomic characters, yield, and disease resistance in order to obtain sorghum varieties and lines with the potential to be developed in plant breeding programs and released as new varieties. The experiment was conducted from February-July 2021 at Leuwikopo Experimental Field and Plant Breeding Laboratory, Department of Agronomy and Horticulture, IPB University. The experimental design used was a randomized complete block design with one genotype treatment factor, in three replications. The result of the analysis of variance, showed that all genotypes had variability in agronomic characters and yield, as well as variability in disease severity, with the exception of leaf rust at 60 and 70 days after planting (DAP), and stem rot. Genotype A-125-1-6-1-6 has the potential to be developed as food and animal feed ingredient. Genotype C-375-17-1-5 has the potential to be developed as food plant with a medium plant height. The pulut 5 genotype has the potential to be used as parents in the production of early-aged sorghum. The breeding lines showed a very resistant response to anthracnose and leaf rust, except for the Soraya 3. Disease resistance reponses in local varieties are resistant and moderately resistant.
Keyword: analisis ragam, genotipe, karakter, keragaman, ketahanan penyakit

Judul: Characterization and Seed Production of IPB Superior Sorghum (Sorghum bicolor L. Moench) Lines
Abstrak: Sorgum (Sorghum bicolor L. Moench) merupakan tanaman alternatif yang dapat dijadikan bahan pangan, pakan, dan sumber bioenergi. Ketersediaan benih berkualiatas dan berdaya hasil tinggi menjadi salah satu kendala petani dalam memproduksi tanaman sorgum. Departemen Agronomi dan Hortikultura IPB telah melakukan upaya pengembangan sorgum melalui persilangan antar varietas unggul. Galur-galur tersebut perlu diketahui kemampuan produksi benih. Karakterisasi juga perlu dilakukan agar mendapatkan informasi mengenai keragaan pada galur-galur tersebut. Penelitian dilakukan di Kebun Percobaan Muara Bogor, Laboratorium Pemuliaan Tanaman, Laboratorium Mikroteknik, dan Laboratorium Penyimpanan dan Pengujian Mutu Benih Departemen Agronomi dan Hortikultura IPB. Rancangan percobaan yang digunakan adalah Rancangan Kelompok Lengkap Teracak (RKLT) dengan faktor tunggal berupa genotipe. Percobaan ini dilakukan sebanyak tiga ulangan, sehingga diperoleh 30 satuan percobaan. Hasil penelitian menunjukkan galur-galur sorgum hasil pemuliaan IPB yang diamati pada penelitian ini memiliki keragaman dalam karakter kuantitatif, yaitu tinggi tanaman, jumlah daun, panjang daun, lebar daun, waktu berbunga, umur panen, bobot malai basah, panjang malai, diameter malai, panjang cabang malai, bobot brangkasan, bobot biji per malai, bobot 1000 butir, dan produksi benih. Selain itu, galur-galur sorgum hasil pemuliaan IPB memiliki keragaman pada karakter kualitatif, yaitu warna tulang daun, warna putik, panjang putik, panjang bunga bertangkai, warna benang sari kering, kerapatan malai, bentuk malai, kemunculan malai, warna sekam, panjang sekam, warna biji, bentuk biji, dan tekstur endosperma. Berdasarkan hasil analisis gerombol, galur sorgum dan varietas pembanding membentuk 3 kelompok, yaitu. kelompok 1 (Soper 6), kelompok 2 (IPB 6), dan kelompok 3 (Samurai 2, Bioguma 1, NS 19, NS 102, dan NS 109). Galur yang berpotensi didaftarkan adalah galur NS 19, NS 102, dan NS 109., Sorghum (Sorghum bicolor L. Moench) is an alternative crop that can be used as food, feed, and bioenergy sources. The availability of quality and highyielding seeds is one of the obstacles for farmers in producing sorghum plants. The Department of Agronomy and Horticulture (IPB) has made efforts to develop sorghum through a breeding program of crosses between superior varieties. These lines need to be evaluated for their seed production capabilities. Moreover, characterization of morphological characters, yield components and yield is also needed to obtain information about the performance of these lines. The research was carried out at the Muara Bogor Experimental Garden, the Plant Breeding Laboratory, the Microtechnic Laboratory, and the Seed Testing and Storage Laboratory of the Department of Agronomy and Horticulture, IPB. The experimental design used was a Randomized Complete Group Design (RKLT) with a single factor in the form of genotype. This experiment was carried out with three replications, so that 30 experimental units were obtained. The research results revealed that sorghum lines had a diversity in quantitative characters, namely plant height, number of leaves, leaf length, leaf width, flowering age, harvest time, wet panicle weight, panicle length, panicle diameter, panicle branch length, strand weight, seed weight per panicle, weight of 1000 grains, and seed production. Moreover, these sorghum lines show diversity in qualitative characters, namely leaf bone color, pistil color, pistil length, stemmed flower length, dry stamen color,, panicle density, panicle shape, panicle exsertion, husk color, husk length, seed color, seed shape, and type of endosperm.
Keyword: breeding program, diversity, qualitative character, seed availability, varieties

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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