Judul: Analisis Genetik dan Seleksi Generasi Awal Segregan Gandum (Triticum aestivum L.) Berdaya Hasil Tinggi
Abstrak: Seri penelitian pemuliaan pendahuluan untuk mengembangkan varietas adaptif pada gandum hingga dataran rendah dan menengah telah dilakukan. Dimulai dari evaluasi dan identifikasi respon agronomi beberapa varietas introduksi, hibridisasi selektif dan pengembangan populasi pemuliaan, hingga seleksi pada generasi awal untuk mengidentifikasi segregan potensial berdaya hasil tinggi. Eksperimen lapangan pertama dilakukan di dua agroekosistem Indonesia (BIOTROP sebagai perwakilan dataran rendah dan Cipanas sebagai perwakilan dataran tinggi) dari Mei hingga September 2011 dan lainnya dilakukan di Stasiun Penelitian BALITHI, Cipanas. Hasil percobaan pertama menunjukkan bahwa lokasi berpengaruh nyata terhadap penampilan gandum. Temperatur yang tinggi di dataran rendah menurunkan kapasitas sink-source, mempercepat periode pengisian benih, dan meningkatkan floret kosong. Genotipe yang diuji diklasifikasikan menjadi tiga tingkat toleransi. Oasis diklasifikasikan sebagai genotipe toleran, HP1744, LAJ, Menemen, Alibey, Selayar, dan Dewata diklasifikasikan sebagai genotipe toleran sedang, dan Rabe, H-21, G-21, G-18, dan Basribey diklasifikasikan sebagai genotipe sensitif. Analisis aksi gen pengendali sifat agronomi menunjukkan bahwa semua sifat yang diamati dikendalikan oleh poligenik dengan efek aditif dan epistatik. Jumlah anakan total, jumlah anakan produktif, bobot kering akar tajuk, bobot biji/malai, dan jumlah biji/bidang memiliki korelasi fenotip yang kuat dengan bobot biji/tanaman. Sebaliknya, berdasarkan analisis jalur hanya dua sifat yang berpengaruh langsung tinggi terhadap bobot biji/tanaman. Sifat-sifat tersebut berguna untuk sifat sekunder dalam meningkatkan potensi hasil. Empat sifat terseleksi (bobot biji/tanaman, jumlah anakan produktif, bobot biji/malai, rasio floret kosong) telah digunakan untuk menyusun indeks seleksi. Segregan terpilih dalam populasi Oasis x HP1744 adalah O/HP-F2-87, O/HP-F2-93, O/HP-F2-100, O/HP-F2-106, O/HP-F2-51, O/ HP-F2-6, O/HP-F2-16, O/HP-F2-124, O/HP-F2-92, O/HP-F2-39, O/HP-F2-9, O/HP- F2-26, O/HP-F2-31, dan O/HP-F2-123. S/R-F2- 39, S/R-F2-13, S/R-F2-61, S/R-F2-19, S/R-F2-56, S/R-F2-7, dan S /R-F2-64 adalah segregan terpilih dalam populasi Selayar x Rabe. Selain itu segregasi terpilih pada populasi Dewata x Alibey adalah D/A-F2-34, D/A-F2-13, D/A-F2-99, D/A-F2-22, D/A-F2-70, D/A-F2-4, D/A-F2-33, D/A-F2-80, D/A-F2-25, dan D/A-F2-65. Semua segregan terpilih memiliki penampilan fenotipik yang lebih tinggi pada semua sifat yang diamati daripada tetuanya.
Keyword: gandum, aksi gen, kapasitas bak cuci, kapasitas sumber, seleksi diferensial

Judul: Analisis genetik dan seleksi generasi awal segregan gandum (Triticum aestivum L.) berdaya hasil tinggi
Abstrak: The preliminary breeding research series to develop adaptive variety in wheat to low and medium land regions had been conducted. It was started from evaluation and identification of agronomical responses of some introduced varieties, selective hybridization and development the breeding populations, until selection in early generation to identify high yielding potential segregants. First field experiment was conducted at two Indonesian agroecosystems (BIOTROP as low land representative and Cipanas as high land representative) from Mei to September 2011 and others were conducted at Research Station of BALITHI, Cipanas. The first experiment results showed that location had significant effect on wheat performance. High temperature in low land decrease the sink-source capacity, accelerate the seed filling period, and increase the empty floret. The tested genotypes were classified into three tolerance level. Oasis was classified as tolerant genotype, HP1744, LAJ, Menemen, Alibey, Selayar, and Dewata were classified as medium tolerant, and Rabe, H-21, G-21, G-18, and Basribey classified as sensitive genotypes. Analysis of agronomical traits-controlling gene action showed that all of observed traits controlled by poligenic with additive and epistatic effects. The total tillering number, productive tillering number, shoot-root dried weight, seed weight/panicle, and seed number/pland had strong phenotypic correlation with seed weight/plant. On the other hand, based on path analysis only two traits which had high direct effect to seed weight/plant. Those traits are useful for secondary trait in improving yield potential. Four selected traits (seed weight/plants, productive tillering number, seed weight/panicle, ratio of empty floret) had been used to develop an selection index. Selected segregants in Oasis x HP1744 population are O/HP-F2-87, O/HP-F2-93, O/HP-F2-100, O/HP-F2-106, O/HP-F2-51, O/HP-F2-6, O/HP-F2-16, O/HP-F2-124, O/HP-F2-92, O/HP-F2-39, O/HP-F2-9, O/HP-F2-26, O/HP-F2-31, dan O/HP-F2-123. S/R-F2- 39, S/R-F2-13, S/R-F2-61, S/R-F2-19, S/R-F2-56, S/R-F2-7, and S/R-F2-64 are selected segregants in Selayar x Rabe population. In addition selected segregants in Dewata x Alibey population are D/A-F2-34, D/A-F2-13, D/A-F2-99, D/A-F2-22, D/A-F2-70, D/A-F2-4, D/A-F2-33, D/A-F2-80, D/A-F2-25, dan D/A-F2-65. All of the selected segregants have higher phenotypic performance in all observed traits than their parents.
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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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