Judul: Serangan Oryctes rhinoceros L. (Coleoptera: Scarabaeidae) di Perkebunan Kelapa Sawit PTPN III Rambutan, Sumatera Utara.
Abstrak: Kelapa sawit (Elaeis guineensis Jacq.) merupakan tanaman perkebunan yang memiliki peran penting di Indonesia yang dapat membuka banyak lapangan pekerjaan dan meningkatkan devisa negara. kumbang tanduk merupakan hama penting tanaman kelapa sawit. Pengendalian hama kumbang tanduk yang dilakukan kebun Rambutan masih mengandalkan insektisida sintetik. Pengendalian alternatif yang dapat dilakukan untuk mendukung kegiatan PHT yaitu penggunaan feromon agregasi ethyl 4-methyloctanoate. Penelitian ini bertujuan mengetahui intensitas serangan dan populasi kumbang tanduk pada tanaman yang belum menghasilkan di perkebunan Kelapa sawit PTPN III Rambutan, Sumatera Utara. Pengamatan intensitas serangan kumbang tanduk dilakukan dengan mengambil 50 tanaman contoh di setiap lokasi pengamatan. Hasil penelitian menunjukkan serangan kumbang tanduk terjadi pada semua lahan pengamatan dengan jumlah yang bervariasi. Intensitas serangan dan populasi imago kumbang tanduk tertinggi terjadi di Blok 193., Oil palm (Elaeis guineensis Jacq.) is an estate crop that has an essential role in Indonesia, creating many jobs and increasing the country's foreign exchange. O. rhinoceros is an important pest of oil palm plantations. O. rhinoceros pest control carried out by the Rambutan plantation still relies on synthetic insecticides. Alternative control and support for IPM activities, namely the use of ethyl 4methyl octanoate aggregation pheromone. This study aimed to determine the attack intensity and population of O. rhinoceros on immature plants in the oil palm plantation of PTPN III Rambutan, North Sumatra. Observation of attack intensity of O. rhinoceros was carried out by taking 50 sample plants at each observation location. The results showed that the attack of O. rhinoceros occurred in all areas of observation with varying amounts. The intensity of attack and population of O. rhinoceros imago was highest in Block 193.
Keyword: IPM, pheromone, rhinoceros beetle

Judul: Damage Intensity and Effectivity Test of Pheromone Traps on Oryctes rhinoceros L. (Coleoptera: Scarabaeidae) in Coconut Plantation Indragiri Hilir Regency, Riau
Abstrak: Kelapa (Cocos nucifera L.) merupakan tanaman serbaguna yang memiliki nilai ekonomi tinggi jika dikelola dengan baik. Provinsi Riau merupakan salah satu penghasil kelapa terbesar di Indonesia dengan nilai kontribusi produktivitas mencapai 14%. Hama yang banyak menyerang kelapa maupun kelapa sawit yaitu kumbang badak. Salah satu metode aman lainnya sebagai pengendalian alternatif dan mendukung kegiatan PHT yaitu penggunaan feromon. Feromon yang dipakai dalam mengendalikan kumbang badak yaitu jenis feromon agregasi ethyl 4- methyloctanoate yang berfungsi untuk menarik kumbang jantan maupun kumbang betina. Penelitian ini bertujuan untuk menghitung intensitas serangan Oryctes rhinoceros dan mengetahui efektivitas beberapa jenis perangkap feromon dalam memerangkap kumbang badak (O. rhinoceros L.) pada tanaman kelapa di Kabupaten Indragiri Hilir, Riau. Penelitian ini dilakukan dengan pengamatan secara langsung pada perkebunan kelapa rakyat di delapan lokasi dengan menggunakan tiga perlakuan perangkap feromon dengan desain yang berbeda-beda. Pengamatan intensitas serangan kumbang badak dilakukan dengan mengambil 20 tanaman contoh di setiap lokasi pengamatan. Hasil penelitian menunjukkan bahwa serangan O. rhinoceros terjadi pada semua lahan pengamatan dengan jumlah yang bervariasi. Intensitas serangan dan luas serangan tertinggi terjadi di Pekan Kamis. Hal ini disebabkan Pekan Kamis didominasi tanaman kelapa, tumpukan bahan organik dan limbah kelapa. Desain perangkap feromon A dapat menangkap O. rhinoceros lebih banyak dibandingkan perangkap feromon B dan C. Perlakuan semua perangkap dengan feromon dalam desain yang berbeda-beda, memerangkap imago O. rhinoceros betina dengan jumlah yang lebih banyak dibandingkan imago O. rhinoceros jantan. Kata kunci: feromon agregasi, kumbang badak, PHT, Coconut (Cocos nucifera L.) is a versatile plant with a high economic value if appropriately managed. Riau Province is one of the largest coconut producers in Indonesia, with a productivity contribution of 14%. Pest that attacks coconut and palm oil is the rhinoceros beetle. One of the other safe methods as an alternative control and supporting IPM activities is the use of pheromones. The pheromone used in controlling the rhinoceros beetles is a type of ethyl 4-methyloctanoate aggregation pheromone that serves, to attract male and female beetles. This study aims to calculating the damage intensity Oryctes rhinoceros and determine the effectiveness of several types of pheromone traps in trapping rhinoceros beetles (Oryctes rhinoceros L.) on coconut plants in Indragiri Hilir Regency, Riau. This study was conducted by direct observation on coconut plantations in eight locations using three pheromone traps treatments with a different design. Observation of the intensity of rhinoceros beetle attacks was carried out by taking 20 sample plants at each observation location. The result showed that O. rhinoceros attacks occur on all observation areas with varying amounts. The intensity of the attack and the extent of the attacks were highest in Pekan Kamis, because Pekan Kamis has a higher coconut plant population, piles of organic matter and coconut waste. The design of pheromone trap A can catch more O. rhinoceros than pheromone traps B and C. Treatment of all traps with pheromones in different design, trapping female O. rhinoceros imago with more numbers than male imago O. rhinoceros. Keyword: aggregation pheromone, IPM, rhinoceros beetle
Keyword: aggregation pheromone, IPM, rhinoceros beetle, feromon agregasi, kumbang badak, PHT

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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