Judul: Biologi dan Preferensi Makan Doleschallia bisaltide Cramer (Lepidoptera: Nymphalidae) pada Graptophyllum pictum (L.) Griff. dan Asystasia gangetica (L.) Anders.
Abstrak: Handeuleum atau daun ungu (Graptophyllum pictum (L.) Griff) termasuk dalam famili Acanthaceae yang merupakan salah satu tumbuhan obat tradisional dan saat ini banyak digunakan masyarakat untuk dijadikan sebagai obat. Salah satu kendala dalam budidaya tanaman handeuleum yaitu adanya serangan ulat Doleschallia bisaltide (Lepidoptera: Nymphalidae). Selain menyerang tanaman handeuleum, hama ini juga memakan tanaman gulma Asystasia gangetica (L.) Anders. Penelitian ini bertujuan mengetahui biologi dan preferensi makan D. bisaltide pada tanaman G. pictum dan A. gangetica. Penelitian dilakukan di rumah kaca Kelompok Peneliti Hama dan Penyakit, Balai Penelitian Tanaman Obat dan Aromatik, Bogor dari bulan Februari sampai Juli 2010. Untuk metode tanpa pilihan, sebanyak 30 diberi makan daun G. pictum dan 30 larva diberi makan daun A. gangetica. Untuk metode pilihan, sebanyak 30 larva diberi makan daun G. pictum dan A. gangetica. Setiap satu larva dipelihara di dalam satu cawan Petri. Penggantian makan dilakukan setiap hari. Parameter yang diamati adalah lama stadia perkembangan dan perilaku, siklus hidup, dan preferensi makan. Analisis data dalam penelitian ini diolah dengan menggunakan software Microsoft Excel 2007. Data preferensi makan dengan metode tanpa pilihan dan metode pilihan dianalisis dengan uji t. Hasil penelitian menunjukkan rata-rata stadia telur, larva, pupa, imago dengan pemberian pakan daun G. pictum secara berturut-turut adalah 3,00 ± 0,00; 16,77 ± 1,61; 8,23 ± 0,50; 10,47 ± 7,18 (jantan) dan 12,27 ± 6,35 hari (betina). Rata-rata stadia telur, larva, pupa, imago dengan pemberian pakan daun A. gangetica secara berturut-turut adalah 3,00 ± 0,00; 18,90 ± 0,92; 7,93 ± 0,25; 18,83 ± 8,30 (jantan) dan 18,28 ± 6,06 hari (betina). Rata-rata stadia telur, larva, pupa, imago dengan pemberian pakan gabungan kedua daun secara berturut-turut adalah 3,00 ± 0,00; 15,67 ± 0,92; 8,17 ± 0,38; 12,15 ± 4,24 (jantan) dan 13,41 ± 7,61 hari (betina). Siklus hidup pada pemberian pakan daun G. pictum dan pakan pilihan lebih singkat dibandingkan dengan pemberian pakan daun A. gangetica. Pada metode tanpa pilihan, larva mengkonsumsi daun G. pictum dan daun A. gangetica secara berturut-turut yaitu sebesar 314,70 ± 92,27 cm² dan 550,38 ± 93,86 cm². Pada metode pilihan, larva mengkonsumsi daun G. pictum dan daun A. gangetica secara berturut-turut yaitu sebesar 214,40 ± 69,85 cm² dan 246,38 ± 69,07 cm². Pada kedua metode pengujian preferensi makan menunjukkan bahwa larva D. bisaltide lebih banyak mengkonsumsi daun A. gangetica dibandingkan dengan daun G. pictum dan menunjukkan hasil yang berbeda nyata.
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Judul: Praseleksi Sifat Resistensi Tanaman Handeuleum [Graptophyllum pictum (L.) Griff.] terhadap Doleschallia bisaltide Cramer (Lepidoptera: Nymphalidae)
Abstrak: Caricature plant is one of the medicinal plants developed in Indonesia. The leaves of this plant can be used for treating hemorrhoids, cleaning blood especially after uttering and menstruation, rheumatism, and preventing teeth plaque. The biggest problem in caricature plant development is Doleschallia bisaltide (Lepidoptera: Nymphalidae) attack. Resistance variety is one of the ways to solve this problem. Generally, plants have resistance mechanism to prevent herbivore attack. Therefore, it is needed to study caricature plant-D. bisaltide interaction to find varietal control for this insect. The objective of this research is to do early selection on 13 accessions of caricature plant for resistance to D. bisaltide. Moreover, we also interest to identify resistance level of 13 caricature plant accessions to D.bisaltide. This research was divided into three studies, including a) morphology and phytochemical identification on thirteen accessions of caricature plant; b) oviposition preference of adult D. bisaltide on thirteen accessions of caricature plant; and c) D. bisaltide larvae consumption activity preference of on thirteen accessions of caricature plant. All studies were done at Indonesian for Medicinal and Aromatic Crops Research Institute (BALITTRO) from May 2009 until February 2010. Thirteen accessions of caricature plant were come from exploration result of Khumaida et.al in year 2008. Based on qualitative analysis, there were changes in each kind of secondary metabolites after D.bisaltide larvae feeding, there were no change in tannin and alkaloid contains, but there decreases in flavonoid, glycoside, and steroid. It was found increasing of triterpenoid and saponin contain after attack caricature plant leaves. Moreover, there was an increased in calcium and C/N ratio on almost caricature plant accessions. Caricature plant colors tend to influenced adult oviposition preference. Based on all observation, it can be concluded that accession 12 was resistant to D. bisaltide attack with antixenosis mechanism. Accession 1, 2, 5, and 9 were susceptible to D. bisaltide. Chlorophyll might be used as selection character. By this research, we haven’t identified about antibiosis mechanism yet.
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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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