Judul: Keragaman dan korelasi antara peubah pertumbuhan dan produksi pada delapan varietas kacang tanah (Arachis hypogaea L.)
Abstrak: Penelitian ini bertujuan untuk mengamati karakteristik pertumbuhan yang mempengaruhi pengisian polong dan produksi pada delapan varietas kacang tanah. Penelitian dilaksanakan di Kebun Percobaan Lewikopo, Darmaga, Bogor dari Februari hingga Juli 2010. Lokasi penelitian memiliki jenis tanah Latosol. Metode penelitian menggunakan Rancangan Kelompok Lengkap Teracak (RKLT) dengan tiga kali ulangan. Perlakuan terdiri dari satu faktor yaitu delapan varietas kacang tanah sehingga terdapat 24 satuan percobaan. Varietas kacang tanah yang digunakan adalah varietas Badak, Garuda3, Jerapah, Kancil, Mahesa, Singa, Tapir, dan Trenggiling. Analisis data menggunakan uji F dan apabila terdapat pengaruh nyata maka dilanjutkan dengan uji Duncan Multiple Range Test (DMRT). Analisis korelasi dilakukan antara peubah pertumbuhan dan komponen produksi. Hasil percobaan menunjukkan varietas Mahesa memiliki pertumbuhan tajuk yang baik selama pertumbuhan tetapi jumlah polong total dan bobot kering polong per tanaman yang dihasilkan nyata lebih rendah yang berdampak pada rendahnya produktivitas polong dan biji. Varietas Garuda3 memiliki pertumbuhan tajuk yang baik hanya sampai fase pembentukan polong. Jumlah polong total per tanaman yang dihasilkan nyata terendah tetapi baik dalam pengisian polong sehingga menghasilkan persentase polong penuh yang tinggi. Varietas Singa memiliki pertumbuhan tajuk yang rimbun selama pertumbuhan tetapi menghasilkan bobot kering polong yang rendah karena pertambahan jumlah ginofor banyak sehingga kurang dalam waktu pengisian polong dan banyak menghasilkan persentase polong cipo. Varietas Kancil memiliki pertambahan daun, batang, dan polong yang tidak mencolok selama pertumbuhan. Produktivitas polong dan biji yang dihasilkan tinggi yang didukung oleh rata-rata jumlah polong penuh yang dihasilkan tinggi sehingga persentase polong penuh juga tinggi akibat dari waktu pengisian polong yang panjang. iii Varietas Badak memiliki pertumbuhan tajuk yang rimbun selama pertumbuhan dan jumlah polong total dan polong setengah penuh yang dihasilkan nyata lebih banyak serta rata-rata jumlah polong penuh dan polong cipo yang banyak. Akibatnya produktivitas polong yang dihasilkan tinggi tetapi produktivitas bijinya rendah. Varietas Jerapah memiliki pertambahan daun, cabang, ginofor, dan polong yang tidak mencolok selama pertumbuhan dan laju pertumbuhan maksimum dari periode awal bunga sampai pembentukan polong. Varietas Jerapah kurang dalam membentuk polong dilihat dari jumlah polong total dan polong setengah penuh yang dihasilkan nyata lebih rendah dan rata-rata jumlah polong cipo terendah. Varietas Tapir memiliki pertumbuhan tajuk yang terus meningkat selama pertumbuhan dan baik dalam pengisian polongnya sehingga menghasilkan persentase polong penuh yang tinggi. Varietas Trenggiling memiliki laju pertumbuhan yang tidak terlalu mencolok. Jumlah polong total dan polong setengah penuh yang dihasilkan nyata lebih rendah tetapi dapat menghasilkan produktivitas polong dan biji yang tinggi. Korelasi antara parameter pertumbuhan dengan komponen hasil menunjukkan bahwa persentase polong penuh dipengaruhi oleh bobot kering ginofor saat pembentukan polong dan bobot kering polong saat menjelang panen. Persentase polong cipo dipengaruhi oleh bobot kering ginofor dan bobot kering polong saat menjelang panen. Indeks panen tanaman dipengaruhi oleh ILD selama pertumbuhan dan CGR saat menjelang panen. Produktivitas polong dipengaruhi oleh hasil indeks panen sementara itu produktivitas biji dipengaruhi oleh persentase polong penuh.
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Judul: Keragaman dan Korelasi Antara Peubah Pertumbuhan dan Produksi pada Delapan Varietas Kacang Tanah (Arachis hypogaea L.).
Abstrak: The objective of this research was to identify growth characteristic that affect the pods filling and production of eight varieties of groundnut. This research was conducted at the Lewikopo Experimental Farm, Darmaga, Bogor from February to July 2010 on Latosol soil. The varieties of groundnut in this experiment were Badak, Garuda3, Jerapah, Kancil, Mahesa, Singa, Tapir, and Trenggiling. Data analysis used the F test and if there was significant difference then followed by Duncan Multiple Range Test (DMRT). Correlation analysis between growth and production variables. The results showed that Mahesa variety had a good canopy during the growth but the number of pods and pods per plant dry weight were significantly lower that influenced low productivity. Garuda3 variety had a good canopy until pods formation phase. The number of pods per plant was significantly lower but good in pods filling and had a high percentage of full pods. Singa variety had a lush canopy during the growth but the pods dry weight was low because had a lot of the number of gynophorum and percentage cipo pods was high. Kancil variety had not noticeable growth of leaves, branches, and pods during growth. Productivity of pods and seeds were high, supported by the average number of full pods high so the percentage of full pods also high due to the long time of pods filling. Badak variety had a lush canopy during the growth and the number of pods and half full pods were significantly and the average number of full pods and cipo pods were high. Jerapah variety had not noticeable growth of leaves, branches, gynophorums, and pods during the growth and maximum growth rate at early flowering time until the pods formation phase. Jerapah variety less in shaping of pods and the number of pods and half full pods were significantly lower and the average number of pods cipo was lower. The canopy of Tapir variety increased during the growth and well in pods filling and had a high percentage of full pods. Trenggiling variety had the number of pods and half full pods were significantly lower but could produced high productivity of pods and seeds. Correlations between growth and production variables showed that the percentage of full pods affected by the gynophorum dry weight at pods formation phase and pods dry weight at toward harvest. Percentage of cipo pods affected by gynophorum dry weight and pods dry weight at toward harvest. Harvest index affected by the ILD during growth and CGR at towad harvest. Pods productivity affected by harvest index and seeds productivity affected by the percentage of full pods.
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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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