Judul: Keragaman Genetik, Heritabilitas, Dan Analisis Koefisien Lintasan Pada Plasma Nutfah Gandum (Triticum Aestivum L.) Koleksi Balitbiogen
Abstrak: The aims of this experiment are to study the geneUc variation, heritability of the wlleat germplesm collection and cotrelation among chafllctelS using pathcoefficient analysis. This experiment was conducted at Rice Research Station in Kuningan, West Java on June until October 2002 using RandOmized Completely Block Design (RCBD) with three replications. each of the twenty-seven genotypes of wheat was planted on four rows with 3 m lenght. The interrow and interplant spacing were 25 em and 10 em, respectivity. Deta obtained from the twenty-seven genotypes were subjected to variance analysis and the heritability of the traits _mated by component of variance method. Correlation coefflcients were computed according to the formula of Goulden (1959). Direct and indirect path coefflcients were calculated as described by Dewey and Lu (1959). High geneUc varianon displayed by l00-grain weight, numberofUllelS per plant and number of spikes per plant The esUmation of heritability ranged from 0 to 94.58%. The days to nower, plant height, spike length, number of greins per spike, and l00-grain weight were uncotrelated with grain yield per plant. In the other hand, the days to harvest, number of tillelS per plant, number of Spikes per plant, dry spikes weight, and harvest spikes weight were positively and significanty correlated with grain yield per plant. The number of graints per plant, number of spikes per plant, number of grains per spike, and l00-grein weight each had a posiwe direct effect on grain yield per plant. The indireci effect on grain yield per plant via number of tillers and number of Spikes (productive tillers ) per plant showed by days to harvest, dry Spikes weight, and harvest Spikes weight. The number of productive tillers per plant was a good criteria to be used towards improvement of grain yield.
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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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