Judul: Eksplorasi Cendawan Entomophthorales dan nematoda pada trips dan kutudaun pada tanaman mawar dan krisan di Balai Penelitian Tanaman Hias Kabupaten Cianjur
Abstrak: Rose and chrysanthemum are two of the ornamental plants that have a high economic value in Indonesia. Thrips and aphid are important pests of these plants. Entomophthoralean fungus and nematode are potential biological control agents of thrips and aphid. There are no many reports of this fungus in Indonesia. The objective of this research was to explore Entomophthoralean fungus and nematode on both thrips and aphids at both roses and chrysanthemums in Indonesian Ornamental Crops Research Institute (Balithi). The research was conducted from March 2012 to June 2012. Thrips and aphids were sampled from three blocks for each plant. Numbers of sampled plants for each block were 10 plants selected randomly. Thrips were sampled at one flower on each plant. Both thrips and aphid samples were put on alcohol 70% for the next experiment. Microscope slide squash mounts in lactophenol cotton blue were made for both thrips and aphids and each sampled insect was examined with a microscope to determine if secondary conidia, hyphal bodies, primary conidia, conidiophores, and resting spores were present. Primary conida, secondary conidia, and hyphal bodies are development stages of fungus were found in thrips. Primary conidia, conidiophores and hyphal bodies were found in aphid. Thrips populations on rose and chrysanthemum were not significantly different. However, fungus infection levels on thrips and aphid showed significant differences. During examination, nematodes were found in thrips on both roses and chrysanthemums. Nematode infection levels in thrips on roses were higher than those on chrysanthemums.
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Judul: Eksplorasi Cendawan Entomophthorales pada Beberapa Spesies Kutuputih dan Kutukapuk pada Berbagai Tanaman Hias di Bogor dan Cianjur
Abstrak: The ornamental plants are the ones of the high economic valued horticultural crops that have beauty and a certain appeal. However, there are several problems of the cultivation efforts to meet consumen desire to face a variety of problems, especially plant pests (OPT), such as insect pests, fungi, bacteria, viruses, and nematodes. The mealybugs (Hemiptera: Pseudococcidae) and ground pearls (Hemiptera: Margarodidae) have been considered as the important pests causing seriously problems in ornamental plants. The objective of this research was to explore the Entomophthoralean fungi associated with several species of mealybugs and ground pearls. The insects were sampled from September 2012 until February 2013, at the Village Babakan raya (District Darmaga) and Cibeber District, Cianjur. There were five sampled ornamental plants. Fifty insects were sampled from each plant. The samples were preserved in 30 ml screw cup vials filled with 70% alcohol. These were later processed in the laboratory to confirm presence of entomophthorealan fungus. Microscope slide squash mounts in lactophenol cotton blue were made for the insects on each plant. Each insect was examined with a microscope to determine if secondary conidia, hyphal bodies, conidiophores, primary conidia, and resting spores were present. Developmental stages of the fungus founded were hyphal bodies, primary conidia, secondary conidia, and saprophytic fungi. The fungus infection in mealybug and ground pearls was very different. There was no fungus infection on the ground pearls scoop in ornamental plant, jasmine and anthurium. The entomophthoralean fungus occurred on mealybug in the garden croton, Aspar and Agave with high levels of fungus infection.
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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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