Judul: Variability of Agronomic Characters, Stay Green and Yield of F4 Sorghum Line
Abstrak: Informasi mengenai keragaman karakter agronomi dan stay green diperlukan untuk menghasilkan galur-galur sorgum yang memiliki hasil tinggi. Penelitian ini bertujuan untuk mendapatkan pengetahuan tentang keragaman karakter agronomi dan memperoleh galur-galur sorgum generasi F4 yang memiliki keragaan karakter agronomi, stay green dan hasil yang lebih baik dari galur tetua. Penelitian ini dilaksanakan di Kebun Percobaan Leuwikopo IPB pada bulan Februari hingga Juni 2021. Rancangan percobaan yang digunakan adalah rancangan augmented, RKLT faktor tunggal. Perlakuan yang diberikan terdiri dari 40 galur sorgum F4 hasil persilangan Numbu x Samurai 2 serta 5 varietas pembanding (Numbu, Samurai 2, Bioguma 3, Kawali dan Pahat) yang diulang sebanyak 4 kali. Hasil penelitian menunjukkan bahwa karakter pada galur F4 memiliki nilai heritabilitas yang rendah hingga tinggi. Koefisien keragaman genetik pada galur F4 berkisar antara 0,59-11,36%. Diameter batang, panjang daun, lebar daun, bobot biomas, jumlah daun hijau vegetatif dan generatif, persentase daun hijau serta intensitas hijau daun berkorelasi positif dan sangat nyata terhadap bobot biji per malai.
Keyword: breeding, correlation, photosynthesis, leaf anging, variability

Judul: Variability of Agronomic Characters and Potential Yield of F8 Sorghum (Sorghum bicolor (L.) Moench) Population from Cross of Numbu × Samurai 2
Abstrak: Pengembangan varietas unggul sorgum diperlukan untuk mendapatkan varietas sorgum yang memiliki produktivitas tinggi. Penelitian ini bertujuan untuk menganalisis keragaman karakter agronomi dan menguji daya hasil 29 galur F8 sorgum hasil persilangan varietas Numbu × Samurai 2 serta mengidentifikasi galur yang memiliki potensi hasil lebih baik dari varietas pembanding. Penelitian dilaksanakan di Kebun Percobaan Muara, Bogor pada bulan Agustus sampai November 2023. Rancangan percobaan yang digunakan adalah rancangan kelompok lengkap teracak augmented dengan genotipe sebagai perlakuan. Genotipe yang digunakan terdiri dari 29 galur sorgum (F8) hasil persilangan Numbu × Samurai 2, serta 3 varietas pembanding (Bioguma 1, Kawali, Soper 6 Agritan). Galur F8 ditanam tanpa ulangan, sedangkan 3 varietas pembanding diulang sebanyak 3 kali. Hasil analisis ragam menunjukkan genotipe berpengaruh nyata terhadap beberapa karakter. Heritabilitas pada genotipe uji memiliki nilai yang rendah hingga tinggi berkisar 0,05-0,88. Hasil analisis korelasi menunjukkan bahwa bobot biji per malai berhubungan erat dan positif terhadap karakter tinggi tanaman, panjang daun, lebar daun, diameter batang, bobot malai basah, bobot malai kering, bobot 1000 butir, bobot brangkasan, bobot batang, dan nira. Diperoleh 10 galur terbaik yang berhasil terseleksi yang memiliki komponen hasil tinggi sehingga potensial dikembangkan sebagai varietas sorgum pangan., The development of superior sorghum varieties is needed to obtain high productivity sorghum varieties. This study aims to analyze the diversity of agronomic characters and test the yield of 29 F8 sorghum lines resulting from crossing the Numbu × Samurai 2 varieties and identify lines that have better yield potential than comparison varieties. The research was conducted at the Muara Experimental Garden, Bogor from August to November 2023. The experimental design was arranged in an augmented randomized complete group design with genotype as the treatment. 29 genotypes from Numbu × Samurai 2 of F8 population and varieties Bioguma 1, Kawali, Soper 6 Agritan as check was used in this research. The F8 line was planted without repetition, while the 3 comparison varieties were repeated 3 times. The results of analysis of variance showed that genotype had a significant effect on several characters. Heritability for the test genotypes had low to high values ranging from 0.05-0.88. The results of the correlation analysis showed that seed weight per panicle was closely and positively related to the characteristics of plant height, leaf length, leaf width, stem diameter, wet panicle weight, dry panicle weight, 1000 grain weight, stover weight, stem weight, and sap. The 10 best selected lines have high yield components so that they have the potential to be developed as food sorghum varieties.
Keyword: augmented, correlation, heritability, selection, variability, 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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