Judul: Praktek Budidaya Kakao dan Prospek Pemanfaatan Semut Hitam dan Semut Rangrang untuk Pengendalian Hama Penggerek Buah Kakao di Kabupaten Kolaka, Provinsi Sulawesi Tenggara
Abstrak: Sulawesi Tenggara is one of the center of cocoa plantation in Indonesia. One of the problems faced by farmers is the infestation of cocoa pod borer (CPB). Farmers usually use chemical insecticides to control the pest, although the results are not satisfactory. The aims of this research were to find a cultivation for controlling the CPB, and the effect of the black ants and weaver ant to the attack intensity and seed damage caused by the cocoa pod borer. This research was conducted in cocoa plantation in Desa Lambandia, Kecamatan Lambandia, Kabupaten Kolaka, Sulawesi Tenggara, from April to September 2009. The research included survey of cocoa cultivation practices and utilization of black ant and weaver ant to control the CPB. The results showed that farming practices have been done by farmers, such as pruning, harvesting oftenly, sanitation–but not maximum and not all farmer practice it. To control the pest, farmers rely on insecticides. Biological control using black ant and weaver ant was not used by farmers. Weaver ants could reduce the population of CPB’s eggs, pupae, and adult, the fruit damage and intensity of CPB infestation decreased in the presence of weaver ant.
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Judul: The Attack of the Cocoa Pod Borer, Conopomorpha  cramerella in the Farmer's Plantation Area, Bulukumba Regency, South Sulawesi
Abstrak: Penggerek buah kakao (PBK), Conopomorpha cramerella Snellen (Lepidoptera: Gracillariidae) merupakan salah satu hama penting yang dapat menurunkan kuantitas dan kualitas produksi biji. Penelitian ini bertujuan menentukan tingkat serangan hama PBK berkaitan dengan cara budidaya petani setempat di Kabupaten Bulukumba, Sulawesi Selatan. Penelitian dilakukan di empat kecamatan di Kabupaten Bulukumba, yaitu Kecamatan Gantarang, Herlang, Rilau Ale, dan Ujung Loe. Kegiatan penelitian yang dilakukan adalah menghitung luas areal serangan hama PBK pada tanaman kakao di lahan percobaan, menentukan persentase serangan buah dan tingkat kerusakan biji kakao oleh serangan larva PBK yang diamati dari hasil panen buah kakao, dilanjutkan dengan wawancara petani terkait dengan pemeliharaan tanamannya. Hasil penelitian menunjukkan bahwa luas serangan hama PBK di lahan percobaan, persentase kerusakan buah kakao saat panen dan tingkat kerusakan biji kakao berturut-turut adalah tertinggi ditemukan di Kecamatan Gantarang, berturut-turut adalah 46,67%, 10,81%, dan 31,54%, dan terendah di Kecamatan Herlang sebesar 33,33%, 8,06%, dan 18,27%. Penamanan bibit klon kakao tahan hama PBK, mekanisme perawatan tanaman dengan melakukan pemangkasan cabang, sanitasi lahan, dan rutinitas waktu pemanenan setiap seminggu sekali dapat mengurangi tingkat serangan hama PBK., Cocoa pod borer (CPB), Conopomorpha cramerella Snellen (Lepidoptera: Gracillariidae) is one of the important pests that can reduce the quantity and quality of cocoa beans production. This study aims to determine the level of CPB pest attack related to the cultivation pattern of local farmers in Bulukumba Regency, South Sulawesi. The research was conducted in four sub-districts in Bulukumba Regency, namely Gantarang, Herlang, Rilau Ale, and Ujung Loe sub-districts. The research activity carried out was to calculate the wide area of CPB pest attack on cocoa plantations in the experimental plot, determine the percentage of fruit borer and the severity of cocoa beans by CPB larvae attack observed from cocoa pod harvest, followed by farmer interviews related with its crop maintenance. The results showed that the level of PBK pest attack in the experimental field, the percentage of damage to cocoa pods during harvest and the level of damage to cocoa beans were highest in Gantarang District, which was 46.67%, 10.81%, and 31.54%, and the lowest was in the District Herlang was 33.33%, 8.06%, and 18.27%, respectively. Planting seeds of cocoa clones that are resistant to CPB pests, plant maintenance mechanisms through branch pruning, land sanitation, and routine harvesting times once a week could reduce the level of CPB pests.
Keyword: clone, cocoa beans, CPB, damage, resistance

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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