Judul: Genetic parameters estimation of agronomic and quality traits and selection high yielding sorghum lines in acid soil
Abstrak: Sorghum is a crop that has potential to be developed as an alternative food because sorghum is a source of carbohydrate and the content of protein, calcium and vitamin B1 is higher than corn and rice. Furthermore, sorghum has potency to be developed as raw material for bioethanol. The adaptation of sorghum in dry environment is suitable to be developed on dry land in Indonesia which is dominated by acid soil. The purpose of this study was to obtain genetic parameters of agronomic and quality traits of sorghum in acid soil and to obtain tolerant and high yielding sorghum lines. The study was divided into three experiments conducted at UPTD of Dry Land Tenjo. Genetic material used in experiments 1 and 3 was F4 and F5 generations from crosses between UPCA S1 (sensitive to acid soil) and Numbu (tolerant to acid soil). Genetic material used in the second trial was six mutant lines and four national varieties. The results showed that there was high variation on stem weight, biomass weight, grain weight/plant, total sugar content and harvest index. The variation of the content of amylose, amylopectin and protein was low, while the tannin content showed a wide variation. The result of selection based on grain weight/ plant and biomass weight could potentially generate 14 genotypes tolerant to acid soil and high yielding. Selection based on grain weight/plant and weight of biomass was effective in acid soil.
Keyword: 

Judul: Selection of sorghum mutan line [Sorghum bicolor (L.) Moench] for high yield and bioethanol production in acid soil strees condition With participatory plant breeding approach
Abstrak: Sorghum is one of high value commodities for food and energy security, because two commodities could be cultivated integratedly in one time and space. Sorghum is drought tolerance plant and suitable to be developed in Indonesia dry lands. The major problem of dry land in Indonesia is predominance of acid soil with Al toxicity. Participatory plant breeding program could be introduced in marginal land to improve adoption of the selected lines. The objective of this research was to develop sorghum variety tolerant to acid soil with high productivity of grain and bioethanol through Participatory Plant Breeding approaches. This research consisted of three stages, i.e: (1) evaluation of sorghum mutant lines in acid soil, (2) participatory varietal selection of sorghum mutant lines in acid soil, and (3) preliminary yield trial of selected lines in acid soil. Evaluation of sorghum mutant lines in acid soil was conducted by screening 61 mutant lines developed through gamma irradiation. The selection was conducted in an augmented design in Central-Lampung. Fiveteen lines selected from the screening in acid soil was used in a participatory varietal selection conducted in four different regions in Lampung in mother and baby trials. The prelimenary yield trial was conducted in a randomized complete block design experiment with 24 sorghum lines in three replications in East-Lampung. The results from the screening in acid soil showed that sorghum mutant lines ZH30-29-07, ZH30-30- 07, and ZH30-35-07 were tolerant in acid soil with high grain productivity and mutant lines PSj-60-05, ZH30-35-07, ZH30-29-07, and PSj-96-05 showed high ethanol productivity. The result of the participatory varietal selection showed that there were differences in preference among farmers in one location or between locations to mutant line selection traits, which led to differences in selected lines. Farmers preferred traits were resistance to loging, short maturity, good performance and high panicle weight. Famers selected ZH30-29-07, ZH30-30- 07, and ZH30-35-07 which have resistance to loging and good performance and high panicle weight, and selected B-76 and B-92 mutant line for ideal plant height and short maturity. There were similarity in selected lines between reseachers and farmers in PVS. The similar selection were ZH30-29-07, ZH30- 30-07, dan ZH30-35-07. This result showed that farmers have indigenous knowledge could to used for plant beeding program. Sorghum mutant lines i.e GH-ZB43-07, PSj-95-05, ZH30-29-07, and ZH30-30-07 showed highest grain yield, and ZH30-35-07, BR-ZH30-06-07, and PSj-95-05 showed highest ethanol production in the yield trial compared to national varieties. Mutant line PSj-95- 05 was both highest in grain and ethanol production.
Keyword: 

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.
Keyword: