Judul: The Effect of Pruning Height Difference on Three-leaved Chaste Tree (Vitex trifolia L.) Growth and Production
Abstrak: Tanaman legundi (Vitex trifolia L.) merupakan tanaman yang dimanfaatkan sebagai obat. Daun tanaman legundi mengandung flavonoid (viteksikarpin) dan minyak atsiri yang berkhasiat sebagai trakeospasmolitik, antiasma, dan repellent. Produktivitas daun perlu ditingkatkan dalam budidaya legundi, salah satunya melalui pemangkasan. Penelitian ini bertujuan mengetahui pengaruh tinggi pemangkasan berbeda terhadap pertumbuhan dan produksi legundi. Penelitian ini menggunakan rancangan tersarang (Nested) dengan faktor utama tinggi pangkasan (10 cm, 15 cm, 20 cm, tanpa pemangkasan) dari permukaan tanah dan jumlah cabang primer yang dipelihara (2 dan 3 cabang) sebagai faktor kedua yang tersarang pada faktor utama yang diulang sebanyak 3 kali yang terdiri dari 4 tanaman dalam setiap ulangannya sehingga terdapat 96 satuan percobaan. Penelitian ini menunjukan tanaman tanpa pemangkasan menunjukan hasil terbaik pada aspek pertumbuhan dan produksi, namun tanaman dengan perlakuan pemangkasan menunjukan kecepatan pertumbuhan yang lebih pesat dan berpotensi menyamai pertumbuhan tanaman tanpa pangkas. Tanaman dengan perlakuan tinggi pangkas 20 cm menunjukkan potensi terbaik pada aspek pertumbuhan dan produksi., Three-leaved chaste tree (Vitex trifolia L.) is a plant that being used as a medicine. It leaves contains flavonoid (vitexicarpin) and essential oil that can be use as tracheospasmolytic, anti asthma, and repellent. Leaves productivity on Vitex trifolia cultivation need to be improved and one of the way was by pruning. This study aims to study the effect of different pruning height on Vitex trifolia growth and production. This research consisted two factors and used nested design with 2 treatment factors. The main factor was prunning height difference (10 cm, 15 cm, 20 cm, without pruning) from the soil surface and number of remained primary branches (2 and 3 primary branches) as a second factor that nested on the main factor. This research repeated 3 times and consisted 4 plants in every repetition so that it had 96 experimental units. This research showed that the plants without pruning gave the best results in growth and production aspects, but the pruning treatment plants had faster growth and potentially surpass the without pruning plants growth. The 20 cm pruning height treatment plants potentially give the best results in growth and production aspects.
Keyword: Medicinal plant, Production, Pruning, Three-leaved Chaste Tree

Judul: The Effect of Harvest Interval on Leave Production and Growth of Three-Leaved Chase Tree (Vitex trifolia L.)
Abstrak: Tanaman legundi (Vitex trifolia L.) merupakan salah satu tanaman herbal yang dimanfaatkan masyarakat sebagai obat tradisional namun masih belum banyak diteliti di Indonesia. Tanaman legundi dipanen daunnya untuk diambil bahan aktifnya, yaitu viteksikarpin sebagai fitofarmaka bahan obat asma. Salah satu teknologi penting dalam produksi tanaman obat seperti legundi adalah penentuan waktu panen yang sesuai agar mendapatkan jumlah bagian tanaman maupun senyawa yang akan dimanfaatkan secara optimal. Legundi adalah tanaman tahunan yang daunnya dapat dipanen berulang. Penelitian ini bertujuan mengetahui pengaruh interval panen terhadap pertumbuhan dan produksi daun legundi, dan menentukan interval panen yang tepat. Penelitian dilakukan di Kebun Percobaan IPB di Cikabayan, Dramaga, Bogor pada ketinggian tempat 240 m dpl dan jenis tanah latosol. Penelitian ini menggunakan RKLT faktor tunggal yaitu interval panen (2, 4, 6, dan 8 minggu sekali) dan diulang sebanyak 4 kali. Penelitian ini menunjukkan tinggi tanaman yang dipanen 6 dan 8 minggu sekali selalu bertambah karena tidak sering dipanen. Interval panen 4 minggu sekali menyebabkan pertumbuhan yang baik dan produksi daun legundi tertinggi. Kata kunci: fitofarmaka, tanaman herbal, tanaman obat, viteksikarpin, Three-leaved chaste tree (Vitex trifolia L.) or legundi is a one of herbal plant that being used by people as a traditional medicine, although there was few research in Indonesia. The leaves are harvested to obtain active ingredient and used as phytopharmaca. The main active ingredient that being used to treat asthma. The appropriate harvest time is important in the production of medicinal plants including for legundi. Legundi is a perennial plant and it can be harvested repeatedly. This research aims to study the effects of harvest interval on growth and production of legundi leaves and determine the appropriate harvest interval to obtain the optimum yield. The experiment was conducted at 240 m above sea level on latosol soil. The environment used a single factor RCBD, namely harvest intervals (every 2,4,6, and 8 weeks) and repeated 4 times. This research showed that plants harvested every 6 and 8 weeks grew well based on its height, but the 4-week interval had the highest yield of legundi leaves. Keywords: herbal plant, medicinal plant, phytopharmaca, vitexicarpin
Keyword: herbal plant, medicinal plant, phytopharmaca, vitexicarpin

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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