Judul: Genetic structure of mangosteen (Garcinia mangostana L.). based on morphology and molecular markers
Abstrak: Pengetahuan tentang variabilitas genetik manggis penting untuk program pemuliaan dan sebagai dasar bagi perbaikan tanaman serta peningkatan daya saing. Manggis dikenal sebagai tanaman buah tropika yang mempunyai mekasisme reproduksi secara apomiksis dengan variasi genetik yang sempit. Penelitian tentang variasi genetik pada manggis sudah cukup banyak dilakukan namun belum terverifikasi dengan baik. Informasi tentang struktur genetik serta hubungan antara keragaman morfologi dan genetik belum tersedia. Untuk itu perlu dilakukan serangkaian kegiatan penelitian yang bertujuan untuk: 1). Mempelajari variasi genetik manggis pada tingkat individu berdasarkan karakter morfologi dan molekuler, 2). Mempelajari hubungan antara variasi morfologi dan genetik, dan 3). Mengungkap struktur genetik empat populasi manggis Indonesia berbasis marka molekuler. Kombinasi antara pendekatan morfologi dengan teknik analisis DNA memegang peranan penting dalam studi keragaman dan identifikasi varietas manggis. Pendekatan ini dapat meningkatkan akurasi dan mempersingkat waktu penelitian. Sebelas marka Inter-simple sequence repeat (ISSR) digunakan untuk mengetahui variasi genetik 22 individu manggis dari berbagai wilayah Sumatera. Hubungan antara karakter morfologi dan molekuler dipelajari menggunakan 33 aksesi manggis yang berasal dari Leuwiliang (Bogor-Jawa Barat), Kiara Pedes (Purwakarta-Jawa Barat), dan Pulau Palas (Tembilahan-Riau). Pengamatan morfologi difokuskan pada 10 karakter buah, dan analisis molekuler dilakukan dengan menggunakan 8 primer RAPD dan 5 primer ISSR. Struktur genetik populasi dipelajari dengan menggunakan 106 sampel tanaman manggis dari empat populasi manggis di Indonesia yaitu Purwakarta (Jawa Barat), Kerinci (Jambi), Tembilahan (Riau) dan Bulukumba (Sulawesi Selatan). Data morfologi dianalisis dengan metode Kruskal Wallis. Pengelompokan berdasarkan morfologi, molekuler dan gabungan morfologi dan mplekuler dianalisis dengan program NTSYSpc 2.1. Struktur genetik populasi dianalisis menggunakan program GenAlex 6.2.
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Judul: Studi keragaman morfologi buah manggis (Garcinia mangostana L.) dari lima lokasi sentra produksi di Pulau Jawa
Abstrak: Mangosteen (Garcinia mangostana L.) is originated from Malaysia which was spread to the South East Asia region including Indonesia. Mangosteen has been reported perform apomixis reproduction, and it is due to mangosteen population in Indonesia presumably genetically homogen. The objective of the study is to evaluate variability pattern on fruit morphologies of mangosteen population from five locations of production center in Java Island, those are Leuwiliang (Bogor), Cantayan (Sukabumi), Wanayasa (Purwakarta), these are on West Java, Kaligesing (Purworejo) on Central Java, and Watulimo (Trenggalek) on East Java. Plant sample was taken 10 trees randomly from each location, subsequently 10 fruit samples taken randomly from each tree. Homogeneity of variance analysis was conducted with Bartlett test and followed with analysis of variance that employed to locul number, fruit weight, fruit length, peduncle length, fruit diameter, fruit length-diameter ratio, rind thickness, Total Soluable Solid (TSS), seed number, and fruit sap. Bartlett test analysis showed that for all of location, no variation was found on fruit weight, fruit length, fruit diameter, fruit length-diameter ratio, rind thickness, Total Soluable Solid (TSS), locul number and seed number, except peduncle length that has variation. Various variance pattern for population on all of location was arised on Total Soluable Solid (TSS), but on fruit diameter, locul number, and seed number the variance pattern were homogenous. Those result tends to assumption that the apomixis reproduction was happening on mangosteen, and if there were variation of fruits performance, its due to variation on environment conditions. These showed by means value of each of character.
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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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