Judul: Pelepasan Parasitoid 0pius chromatomyiae Belo kobylskij & Wharton (Hymenoptera: Braconidae) pada Pertanaman Kacang Jogo yang Terserang Lalat Pengorok Daun
Abstrak: Penelitian bertujuan untuk mengevaluasi potensi parasito id 0pius chromatomyiae, khususnya dalam kaitan dengan prospeknya untuk keperluan pelepasan inokulasi dan inundasi dalam pengendalian hayati lalat pengorok daun. Penelitian dilaksanakan sejak bulan Agustus hingga November 2004, di Kebun Percobaan Balai Penelitian Tanaman Hias, Cipanas dan laboratorium Ekologi Serangga, Departemen Proteksi Tanaman, IPB. Penelitian menggunakan tanaman kacang jogo (Phaseolus vulgaris L.) yang telah terinfestasi larva pengorok daun Liriomyza huidobrensis (Blanchard) (Diptera: Agromyzidae). Perlakuan dirancang dalam bentuk petak berpasangan yaitu petak yang dilepasi parasitoid dan petak kontrol, masing-masing dilaksanakan pada tiga blok terpisah sebagai ulangan. Uji-t berpasangan digu nakan untuk menentukan ada tidaknya perbedaan kelimpahan lalat pengorok daun antara petak yang dilepasi parasitoid dan petak kontrol dan untuk membandingkan banyaknya parasitoid 0. chromatomyiae yang muncul dari kedua petak tadi. Untuk menentukan perbedaan banyaknya parasitoid yang muncul pada berbagai jarak dari titik pelepasan digunakan sidik ragam. Seluruh analisis data dilakukan dengan bantuan program MINITAB 13.20. Hasil penelitian menunjukkan bahwa rataan banyaknya pupa L. huidobrensis yang berasal dari petak pelepasan parasitoid dan petak kontrol tidak berb eda nyata (t = -0, 16; P = 0,886) . Banyaknya pupa L. huidobrensis yang muncul dari petak pelepasan dan kontrol menunjukkan banyaknya inang yang. tersedia bagi parasitoid 0. chromatomyiae. Imago 0. chromatomyiae yang mu neut dari daun contoh pada petak pelepasan sebanyak 93 7 ekor, sedangkan pada petak kontrol tidak seekor parasitoid pun muncul. Hasil sidik ragam menunjukkan bahwa rataan banyaknya imago 0. chromatomyiae yang muncul pada berbagai jarak tidak berbeda nyata pada hari ke-1, -2, maupun -3 setelah pelepasan Tidak .adanya perbedaan nyata pada hari ke-1 menunjukkan bahwa parasitoid 0. chromatomyiae mampu memencar dalam radius 2 m dalam kurun waktu 24 jam setelah dilepaskan. Pada hari-hari berikutnya diperkirakan bahwa parasitoid telah memencar lebih jauh lagi. Tingkat parasitisasi pengorok daun oleh 0. chromatomyiae pada · hari ke-1, -2, dan · -3 setelah pelepasan berturut-turut adalah 27,04%, 24,38%, dan 29,22%. Tingkat parasitisasi tersebut dicapai dalam waktu 24 jam setelah tanaman umpan diletakkan di lapangan, dengan jumlah parasitoid yang dilepaskan sekitar 50 pasang. Parasitoid 0. chromatomyiae berpotensi digunakan dalam pengendalian hayati lalat pengorok daun.
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Judul: Lalat penggorok daun Liriomyza spp. (Diptera: Agromyzidae) dan parasitoidnya pada sayuran dataran tinggi dengan perhatian utama pada parasitoid Opius chromatomyiae Belokobylskij & Wharton(Hymenoptera: Braconidae)
Abstrak: Leafminers Liriomyza spp. are major pest on highland vegetables in Indonesia. The objectives of the research were to (1) evaluate leafminer and its parasitoids on higland vegetables, (2) study the intensity of parasitism of O. chromatomyiae in various host plants, (3) study the population dynamic of leafminer and its parasitoid in shallot, (4) evaluate the impact of three insecticides on parasitoid O. chromatomyiae, and (5) evaluate the demographic parameters and functional response of parasitoid O. chromatomyiae. Surveys of leafminer population and its parasitoid were undertaken by collecting 20-40 infested leaves. Leafminer flies and parasitoids emerged were collected and identified. Level of parasitism was calculated based on the number of parasitoids emerged divided by the total number of flies and wasps emerged. The population dynamic of leafminer and its parasitoids were studied on two varieties of green onion, by collecting 20 leaves and counting number of flies catched on yellow traps every week. The impact of insecticides on both leafminers and parasitoids was conducted by applying three different insecticides: abamectin, azadirachtin, and cartaphydrochloride once a week at the recommended dosage. Life table of O. chromatomyiae was studied to determine the population growth potential of the parasitoid, by calculating reproduction rate, intrinsic rate of increase, generation time, and stable age distribution. Functional response was evaluated by exposing O. chromatomyiae on the third instar larvae of L. huidobrensis at eight different host densities (2, 4, 8, 10, 12, 16, 20, and 24) of. Our surveys revealed that Liriomyza huidobrensis, L. sativae, L. chinensis and Chromatomyia horticola were associated with various highland vegetables. Eight parasitoids emerged from leafminer-infested leaves: Hemiptarsenus varicornis, Asecodes deluchii, Neochrysocharis okazakii, N. formosa, Neocrhysocharis sp. Quadrastitchus liriomyzae, O. chromatomyiae and Gronotoma micromorpha. Parasitoid Opius chromatomyiae emerged from 13 different species of vegetables infested by leafminers.. Number of leafminers and parasitoids emerged, and crop damage were significantly different between two green onion varieties tested. Cartap hydrochloride was the most effective insecticide in term for reducing leafminer populations. Even though not as effective as cartap hydrochloride, abamectin and azadirachtin could reduce level of leafminer damage and had lower detrimental effects on natural enemies. Life table studies showed that longevity of females Opius chromatomyiae (9.95 days) shorter than males (11.73 days). Females laid 104.73 eggs with the oviposition rate was 9.31 eggs/days. Reproductive output (R0) was 28.55 with generation time (T) was about 15.96 days and intrinsic rate of increase was 0.21. The stable age ditribution was 37.93% eggs, 24.92% larvae, 20.36% pupae and 16.78% adults. Functional response of O. chromatomyiae is type II (hyperbolic curve) with searching time was 0.0777/hour and handling time was 2.5818/hour.
Keyword: Bawang Daun, Endoparasitoid, West Java

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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