Judul: Selection of Quorum Quenching Activity and Natural Defense of Tapak Tuan Patchouli (Pogostemon cablin) aiiA Gene Transgenic against Bacterial Wilt of Ralstonia solanacearum.
Abstrak: Pogostemon cablin Benth memiliki kendala budidaya yaitu layu bakteri yang disebabkan oleh Ralstonia solanacearum. Penggunaan varietas resisten dari tanaman transgenik diharapkan dapat mengendalikan layu bakteri. Tujuan dari penelitian ialah menyeleksi aktivitas quorum quenching nilam Tapak Tuan transgenik yang telah disisipkan gen aiiA terhadap R. solanacearum. Tahapan penelitian meliputi seleksi klon transgenik aiiA terhadap R. solanacearum yang dianalisis menggunakan uji Kruskal Wallis pada kondisi in vitro dan pengamatan pertumbuhan klon transgenik pada kondisi in planta. Kemudian, mengukur aktivitas asam jasmonat dan aktivitas enzim peroksidase serta polifenol oksidase pada klon transgenik terpilih. Ekspresi gen aiiA terkuat diketahui berasal dari klon aiiA 5 yang memiliki rata-rata gejala layu 35,92% dengan penekanan gejala layu 27,38%. Klon terpilih Aiia 5 memiliki aktivitas asam jasmonat sebesar 9,832%, aktivitas enzim peroksidase sebesar 47,45%, dan aktivitas enzim polifenol oksidase sebesar 22,22%. Klon aiiA 5 memiliki tingkat pertumbuhan tertinggi pada kondisi in planta yaitu sebesar 1,10 cm. Klon aiiA 5 memiliki ekspresi gen aiiA dan aktivitas quorum quenching terkuat., Pogostemon cablin Benth has a cultivation problem, namely bacterial wilt caused by Ralstonia solanacearum. The use of resistant varieties of transgenic plants is expected to control bacterial wilt. The aim of the study was to select the quorum quenching activity of transgenic Tapak Tuan patchouli that had aiiA gene inserted against R. solanacearum. The stages of the research included selection of aiiA transgenic clones against R. solanacearum which were analyzed using the Kruskal Wallis test in in vitro conditions and observing the growth of the transgenic clones in in planta conditions. Then, measuring the activity of jasmonic acid and the activity of peroxidase enzymes and polyphenol oxidases in selected transgenic clones. The strongest aiiA gene expression was found to be from clone aiiA 5 which had an average of 35,92% wilt symptoms with an suppression of 27,38% of wilt symptoms. The selected clone Aiia 5 had jasmonic acid activity of 9,832%, peroxidase enzyme activity of 47,45%, and polyphenol oxidase enzyme activity of 22,22%. Clone aiiA 5 had the highest growth rate in planta conditions, namely 1,10 cm. Clone aiiA 5 had the strongest aiiA gene expression and quorum quenching activity.
Keyword: aiiA gene, patchouli, quorum quenching, Ralstonia solanacearum, resistance

Judul: Induction of somaclone variation through gamma irradiation and in vitro selection to obtain drought tolerance patchouly
Abstrak: Tanaman nilam (Pogostemom cab/in Benth.) merupakan salah satu tanaman penghasil minyak atsiri yang dikenal dengan minyak nilam (patchouly oil). Indonesia merupakan negara pemasok terbesar kebutuhan minyak nilam dunia, yang mencapai sekitar 90 % dari seluruh kebutuhan dunia. Tanaman nilam umumnya dibudidayakan pada lahan kering, sehingga salah satu resiko pengembangannya adalah masalah kekeringan. Sempitnya keragaman genetik dan terbatasnya jumlah klon yang tersedia merupakan salah satu kendala dalam melakukan seleksi untuk memperoleh klon unggul yang adaptif terhadap cekaman kekeringan. Penggunaan iradiasi sinar gamma pada kalus nilam yang telah mengalami subkultur berulang merupakan upaya yang dilakukan untuk meningkatkan variasi somaklonal, dan melalui seleksi in vitro menggunakan agen penyeleksi Polyethilene Glycol (PEG), diharapkan diperoleh tanaman nilam yang toleran terhadap cekaman kekeringan sebagaimana tujuan clari penelitian ini. Penelitian dilaksanakan di Lab.Biologi Sel dan Jaringan Pusat Penelitian dan Pengembangan Bioteknologi dan Sumberdaya Genetik Pertanian Bogor. Iradiasi sinar gamma dilaksanakan di Pusat Aplikasi Teknologi Isotop dan Radiasi (PATIR) Badan tenaga Atom Nasional (BATAN) Jakarta. Penelitian berlangsung dari Juli 2004 s/d Januari 2007. Bahan tanaman yang digunakan adalah klon nilam Tapak Tuan (TT75) basil perbanyakan secara in vitro dan merupakan salah satu klon harapan yang dikoleksi Balitbiagen., Patchouly (Pogostemon cab/in Benth.) is a source of patchouly oil. Indonesia is the biggest producer of patchouly oil in the world, reach to 90 % supply. Generally, patchouly is cultivated at dry land so that drought stress becomes the one of problem for this development. Low level of genetic diversity and limitation of clones are also the other problem to get superior clone that adaptive to drought stress. The use of gamma irradiation of fragment sub culture calli is the one alternative way to increase somaclonal variation and via in vitro selection using PEG as the selective agent is expected to obtain drought tolerance patchouly. The research was conducted at the Tissue Culture Laboratory of Research Center of Biotechnology and Genetic Resources, Bogor. Gamma irradiation treatment was done at the Center for Application of Isotope and Radiation •Technology-BAT AN, Jakarta from July 2004 to January 2007. Plant material was Tapak Tuan clone obtain from in vitro proliferation and the one of the most expection candidate clone that Balitbiogen collected.
Keyword: Calli, Somaclonal variation, Gamma inadiation, Pohjelilene glycol

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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