Judul: Agronomic improvement characters and adaptation to drought stress on soybean [Glycine max (l) merr] through low doses of gamma rays irradiation
Abstrak: The increase in genetic variability of soybean plants improve the probability to select for desired characters, for example, adaptation to drought stress. Mutation breeding is a breeding methods that can be applied to improve genetic variability of soybean in a relatively short time. Similarly, mutation induction can also increase genetic variability of soybean by using low doses of gamma rays irradiation. The objectives of the research were : (1) to obtain information on the changes in morphological and agronomic characters due to the treatment of low doses of gamma rays irradiation on plant population; (2) to obtain information on genetic variability among irradiation doses in plant population; (3) to obtain mutant putative genotype with good morphological and agronomic characters on optimum as well as stress condition; (4) to obtain information on the character of physiological adaptation to drought and plants; and (5) to obtain to a mutant putative line which can tolerate drought and high yielding. The study result showed that in Lethal Dose 50 (LD50) value there were 457,13 Gy. Gamma ray irradiation produced four populations that showed different growth and development from the non-irradiated control (Argomulyo). Genetic variability of each trait was different in each population at M2 generation. The selection based on number of productive pods and weight of seed per plant resulted in a mean improvement of selected genotype compared to the mean of base populations in M3 generation, respectively. Putative mutant lines on M4 that was from M3 selection had a mean improvement of plant height, number of productive nodes and number of productive pods better than that of Argomulyo variety. There were different responses of drought tolerant varieties (Ceneng and Tanggamus) and drought sensitive varieties (Anjasmoro and Argomulyo) to soil water content. The escape mechanism was found as earlier maturity in Argomulyo variety. Avoidance mechanism due to the increase in root volume was found in Anjasmoro, Ceneng and Tanggamus varieties at 40 % field capacity. Tolerance mechanism was marked by the reduction of evapotranspiration in Tanggamus variety at 40 % field capacity. The research results showed that the performance of agronomic characters on drought condition were lower than that of in optimum condition in M5 population. The selection result on M5 generation indicated that the selected mutant strains had good agronomic characters and high yielding. They had good adaptability to drought and were high yielding in optimum conditions and drought conditions.
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Judul: Adaptation of wheat lines (Triticum aestivum l.) Tolerance high temperature and improved genetic variation through mutation induction using gamma-ray irradiation.
Abstrak: Characteritation of ten wheat introduced genotypes and two varieties of wheat in two seasons and elevations showed different responses tested at any observed agronomical characters. Agronomical and physiological characters with high heritability estimated value and wide genetic variability were plant height, spikelet number and flag leaf area. There were five traits that directly affected seed weight/plant namely number of seeds/spike, number of seeds/plant, chlorophyll a, chlorophyll b and total chlorophyll characters. Index genotype sensitivity to high temperatures vary greatly based on the character were observed, the yield character of OASIS/SKAUZ//4 * BCN Var-28 genotype had a medium tolerance in two seasons. The G-21 and LAJ tolerance can be selected based on weight of seeds/spike, chlorophyll b, and yield characters, while Oasis tolerance can be selected based on the length of spike and grain weight/plant (2010). Genotype Oasis, H-21, and LAJ, Basribey tolerance can be selected based on the weight of seeds/plant and seed weight/spike. The Interaction of genotype x season x elevation significantly affected plant height, days of flowering, number of spikelet, number of floret, seed weight/spike, seed filling rate, yield, flag leaf area, stomata density, chlorophyll b and the leaves greeness characters. There only the location x genotype interactions affected the harvest, percent floret sterile, the number of seeds/panicle, 1000 grain weight, number and weight malai/m2 seeds/plants. Two genotypes had higher yield than comparable varieties Selayar the Basribey (2.00 t.ha-1) and Alibey (2.13 t.ha-1) in both elevation and two seasons. The HP 1744 is a stable genotype (1.75 t.ha-1), H-21 (1.82 t.ha-1) and varieties Selayar (1.92 t.ha-1). The results showed that the orientation of dose dose> 400 gy cause seedling growth under stress and cause the sprouts do not contain chlorophyll. Dose of 300 gy field research led to the death of 50% of the population in the irradiated plants. Gamma ray irradiation at 300 gy dose did not show significant effect on all the characters in M1 plants. The genetic diversity of the population appears M2 of all strains were irradiated. The characters that unaffected by the season, but only by the location x genotype interactions were the harvest time, percent of hollow floret, the number of seeds/spike, 1000 grain weight, number of spike/m2 and seed weight/plant. Basribey (2.00 t.ha-1) and Alibey (2.13 t.ha-1) genotypes had higher yield than comparator varieties (Selayar) in both elevations and two seasons. The stable genotype were HP 1744 (1.75 t.ha -1), H-21 (1.82 t.ha-1) and Selayar (1.92 t.ha-1) varieties. The results of orientation dose showed that the > 400 gy dosage caused seedling growth experienced stress and the sprouts did not contain chlorophyll. Dose of 300 gy on field research led to the death of 50% of the irradiated plant population. Gamma ray irradiation with dose of 300 gy did not show significant effect on all the characters in M1 plants. The character with moderate to wide genetic variability was harvest time. The number of hollow floret had wide genetic variability excepting in M2 population derived from Selayar varieties. The form of M3 populations at >1000 m asl was better than < 400 m
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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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