Judul: Studi keragaman morfologi tanaman dan semaian populasi manggis (Garcinia mangostana L.) dari tiga sentra produksi di Pulau Jawa
Abstrak: Penelitian ini bertujuan untuk mengevaluasi variabilitas genetik populasi manggis dari tiga sentra produksi di pulau Jawa, Wanayasa (Jawa Barat), Watulimo (Jawa Timur) dan Gunung Walat (Jawa Barat) berdasarkan karakter morfologi pohon induk (indeks luas daun, bobot daun, bentuk tajuk, lingkar batang), karakter buah (bobot biji, bobot buah) dan penampilan bibit (warna siram, tinggi tanaman, jumlah daun, laju siram, indeks luas daun, laju perkecambahan). Penelitian dilakukan di lokasi populasi untuk mengetahui karakter morfologi dan di Tajur Bogor untuk melihat performa bibit pada bulan Maret sampai September 2002. Sepuluh pohon induk dipilih secara acak untuk setiap populasi. Sepuluh buah juga dipilih secara acak dari setiap pohon. Benih untuk analisis penampilan bibit diperoleh dari sepuluh buah dari masing-masing pohon induk, dan disusun dalam Rancangan Acak Lengkap yang terdiri dari sepuluh ulangan untuk Gunung Walat, sepuluh ulangan untuk Wanayasa, dan enam ulangan untuk Watulimo. Data hasil observasi dianalisis dengan analisis homogenitas varians (analisis Bartlet) dan dilanjutkan dengan uji Tukey’s Studentized Range. Analisis homogenitas ragam menunjukkan bahwa indeks luas daun, bobot daun, bobot biji, dan bobot buah mempunyai keragaman yang homogen kecuali bentuk tajuk dan cincin batang. Hasil tersebut menunjukkan bahwa pada parameter yang diamati, variasi sebagian besar disebabkan oleh variasi lingkungan. Data yang dianalisis menunjukkan bahwa di antara pohon-pohon di Wanayasa, Watulimo dan Gunung Walat tidak terdapat perbedaan besar dalam parameter pengamatan. Berdasarkan analisis Bartlett pada performa bibit tidak ditemukan variabilitas genetik pada tinggi tanaman, jumlah daun, laju siram dan indeks luas daun. Namun terungkap bahwa variabilitas genetik terdapat pada warna kemerahan dan kecepatan perkecambahan, variabilitas tersebut diperkirakan disebabkan oleh faktor lingkungan. Selanjutnya terungkap tidak ada perbedaan performa bibit. Uji korelasi menunjukkan bahwa pertumbuhan primer bibit manggis terbukti berkorelasi dengan ukuran benih.
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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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