Judul: Agronomic Character Diversity of Sorghum Lines Derived from Single Seed Descent for Phosphorus Deficiency Tolerance
Abstrak: Sorgum merupakan salah satu jenis tanaman pangan yang berpotensi di Indonesia karena mempunyai adaptasi yang luas. Salah satu adaptasi penting sorgum yaitu memiliki sifat toleran pada lahan defisiensi fosfor. Penelitian ini bertujuan untuk memperoleh korelasi dan informasi tentang keragaan karakter morfologi dan agronomi galur-galur harapan sorgum F7 toleran defisiensi P. Penelitian dilakukan di Kebun Percobaan BB Biogen Bogor dengan menggunakan rancangan kelompok lengkap teracak (RKLT) faktor tunggal sebanyak 3 ulangan. Hasil penelitian mendapatkan galur-galur memiliki pertumbuhan, hasil, dan komponen hasil tidak berbeda nyata dengan toleran, yaitu galur B69/N 115-9, B69/N 114-7, B69/N 331-8, B69/N 170-9, dan B69/N 151-8., Sorghum is a potential food crop in Indonesia because it has wide adaptation. One of the important adaptations of sorghum is tolerance of phosphorus-deficient land. This study aims to obtain information about the morphological and agronomic characters of the promising lines of P-deficiency-tolerant sorghum lines derived from single seed decent. The study was conducted at the ICABRIOGRAD Research Station, Bogor using a randomized complete block design single factor with 3 replications. The results showed that the lines namely B69 / N 115-9, B69 / N 114-7, B69 / N 331-8, B69 / N 170-9, and B69. / N 151-8 had growth, yield, and yield components that were not significantly different from the tolerant lines.
Keyword: Sorgum, single seed descent, phosphorus deficienc

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: 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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