Judul: α-Amylase Inhibitor Gene Expression of Healthy Sengon (Falcataria moluccana Miq) Healthy and Attacked by Boktor Pests
Abstrak: Sengon (Falcataria moluccana Miq) merupakan salah satu pohon pionir dan memiliki berbagai macam kegunaan. Penanaman sengon secara monokultur menimbulkan terjadinya ledakan hama penggerek batang atau boktor (Xystrocera festiva) yang merusak kayu dan menjatuhkan nilai jual batang sengon. Studi molekuler aktivitas gen α-amilase inhibitor (AAI), yang merupakan salah satu gen ketahanan terhadap hama boktor sangat mendukung program pemuliaan sengon. Penelitian ini bertujuan mengkuantifikasi tingkat ekspresi gen α-amilase inhibitor sengon yang sehat dan terserang hama boktor. Prosedur penelitian ini meliputi isolasi RNA total, sintesis cDNA, perancangan primer spesifik gen AAI (target) dan aktin (kontrol), optimasi suhu annealing primer gen AAI dan aktin, ekspresi gen AAI dan aktin pada Real Time PCR dan analisis data. Fragmen cDNA teramplifikasi pada suhu annealing 61,7oC untuk gen aktin dan 61oC untuk gen AAI. Tingkat ekspresi gen AAI 2 pada pohon sengon yang terserang hama boktor memiliki nilai yang lebih tinggi yaitu 55,60 pada sampel 1 dan 6,96 pada sampel 3.
Keyword: Falcataria moluccana, α-Amilase Inhibitor, Real Time PCR

Judul: Ekspresi Gen Trypsin Inhibitor Sengon (Falcataria moluccana Miq.) yang Sehat dan Terserang Hama Boktor
Abstrak: Sengon (Falcataria moluccana Miq.) merupakan salah satu jenis cepat tumbuh yang kayunya banyak dimanfaatkan sehingga sering dibudidayakan terutama di Pulau Jawa. Adanya serangan hama penggerek batang boktor (Xystrocera festiva Thombs) terhadap sengon menyebabkan kerugian yang besar karena dapat menurunkan kualitas kayu dan menurunkan nilai jual kayu sengon. Secara alami tanaman sengon memiliki gen ketahanan terhadap serangan hama boktor, salah satunya adalah trypsin inhibitor. Tujuan penelitian ini adalah membandingkan tingkat ekspresi gen trypsin inhibitor pada kambium pohon sengon resisten dan terserang hama boktor secara kuantitatif dengan teknik Quantitative Real Time PCR. Gen target yang digunakan yaitu trypsin inhibitor (TI) dan gen Actin sebagai internal kontrol dirancang dari analisa data transkriptom sengon. Data Threshold cycle (CT) yang diperoleh kemudian dikuantifikasi menggunakan metode comparative CT method (2 -ΔΔCT). Hasil kuantifikasi menunjukkan tingkat ekspresi gen trypsin inhibitor pada ketiga sampel sengon resisten yaitu sebesar 1.90, 2.20, dan 2,85 sedangkan sengon terserang boktor sebesar 4.07, 2.05, dan 4.08. Rata-rata ekspresi gen trypsin inhibitor pada sengon terserang hama boktor lebih tinggi dibandingkan sengon yang resisten. Kata kunci: Falcataria moluccana, Trypsin Inhibitor, Quantitative Real Time PCR, Sengon (Falcataria moluccana Miq.) is highly demanded fast growing tree species which leads to the increasing sengon cultivation especially in Java. Boktor pest (Xystrocera festiva Thombs) decrease the quality of sengon wood, causing a high loss due to lower selling price of the log. Naturally sengon has resistance gene to defend itself from boktor pest attacks, and one of these genes is trypsin inhibitor. This study aimed to comparing the level of trypsin inhibitor gene expression in sengon’s cambium that is resistant and attacked by boktor pests. The analysis of gene expression level was carried out using the Real Time PCR technique. Primers of trypsin inhibitor (TI) gene as the target gene and Actin gene as the internal control were designed from sengon’s transcriptomic data analysis. Threshold cycle (CT) that obtained then quantified using comparative CT method (2 -ΔΔCT). Quantification results showed that the expression level of trypsin inhibitor from three resistant samples are 1.90, 2.20, and 2,85 while in sengon attacked by boktor are 4.07, 2.05, and 4,08. The average trypsin inhibitor gene expression in sengon attacked by boktor pest was higher than resistant ones. Keywords: Falcataria moluccana, Trypsin Inhibitor, Quantitative Real Time PCR
Keyword: Falcataria moluccana, Trypsin Inhibitor, Real Time PCR

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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