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: Diversity of Mealybugs (Hemiptera: Pseudococcidae) Associated with Entomophthorales Fungi in Various Plants in Prembun District, Kebumen Regency
Abstrak: Kutu putih merupakan hama polifag yang memiliki kisaran inang yang beragam. Tanaman inang utama kutu putih antara lain singkong, pepaya, terung, dan jambu biji. Pengendalian hayati kutu putih secara alami terjadi karena adanya musuh alami, termasuk cendawan entomophthorales. Cendawan tersebut menjadi salah satu agen hayati yang mampu mengendalikan kelimpahan populasi kutu putih di lapangan. Cendawan entomophthorales merupakan cendawan entomopatogen yang bersifat obligat. Kelimpahan populasi kutu putih memengaruhi tingkat infeksi cendawan entomophthorales. Cendawan entomophthoales Neozygtes fumosa dilaporkan mampu menekan populasi kutu putih Paracoccus marginatus. Identifikasi infeksi cendawan entomophthorales dilakukan pada beberapa spesies kutu putih yang diambil dari berbagai jenis tanaman inang. Fase cendawan yang ditemukan selama penelitan adalah primary conidia, secondary conidia, hypal bodies, resting spore dan cendawan saprofit yang berasosiasi dengan cendawan entomophthorales. Tingkat infeksi pada P. marginatus pada tanaman singkong mencapai 50%., The mealybugs are a polyphagous insects and it has been confirmed that there are many plant families to be hosted. The main host plants of mealybugs were cassava, papaya, eggplant, and guava. One of natural biological controls of mealybugs occur in the field is the entomophthorlean fungus. The objective of this research is to determine several species of mealybugs on several plants and their association with the entomophthoralean fungus. Identification of mealybugs and the infection of entomophthoralean fungus were carried out on several species of mealybugs on various of host plants. The results show that there are several species found at several sampled plants. The phase of the entomophthoralean fungi found were primary conidia, secondary conidia, hyphal bodies, and saprophytic fungi. One species of entomophthoralean fungus, Neozygtes fumosa, was found to be able to suppress the population of papaya mealybugs, Paracoccus marginatus. Infection level of this fungus on Paracoccus marginatus in cassava plants reached at 50%.
Keyword: Infection rate, Neozygites fumosa, Paracoccus marginatus, pest control, population

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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