Judul: Kegiatan pembiakan vegetatif tanaman di PT Intidaya Agrolestari Bogor : Studi kasus uji keberhasilan zat pengatur tumbuh roots-g pada pembiakan vegetatif Gmelina arborea Linn.
Abstrak: Tujuan yang ingin dicapai dalam pelaksanaan kegiatan magang mahasiswa ini adalah pelaksana magang dapat memahami prinsip pengelolaan kebun pangkas sebagai sumber bahan untuk perbanyakan tanaman dengan teknik stek pucuk, dapat memahami dan menguasai teknik perbanyakan tanaman dengan stek pucuk dan menguasai pemeliharaan lanjutan sererti pemupukan dan perlindungan dari hama dan penyakit. Pengelolaan kebun pangkas di PT Inagro terkait dengan program lain, namun pada masa sekarang sudah tidak berjalan dengan baik. Kegiatan yang dilakukan hanya sebatas pada pemeliharaan rumah stek saja. Hal ini terjadi karena kegiatan-kegiatan yang melibatkan penggunaan kebun pangkas seperti penelitian-penelitian sudah tidak dilakukan lagi Arah kebijakan perusahaan lebih cenderung pada kegiatan-kegiatan produksi yang bisa menghasilkan pendapatan langsung bagi perusahaan. Permasalahan-permasalah lain yang dihadapi di kebun pangkas adalah adanya lokasi kebun pangkas yang tergenang air, sehingga pertumbuhan tanaman induk terganggu dan bahkan banyak pula yang mati. Selain itu faktor keamanan juga menjadi masalah, karena banyak sekali sarana-sarana di kebun pangkas yang hilang. Permasalahan-permasalahan tersebut diatas bersumber pada berubahnya kebijakan perusahaan dalam mensikapi kondisi perusahaan yang tidak menguntungkan....
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Judul: Pengaruh pemberian ZPT (Rootone-F) terhadap pertumbuhan stek Duabanga moluccana, Blume.
Abstrak: INTRODUCTION Insufficient supply of raw materials to support wood based industries in Indonesia cause of the changes on orientation for wood supply from natural forest to plantation forest in developing fast growing tree species. Duabanga mollucana Blume, is an Indonesian native fast growing tree species that have good characteristic as raw materials for wood based industries. Vegetative propagation can be done to this species besides their ability to be propagated from seed. Shoot and stem cuttings are alternative ways to obtain qualified seedlings in appropriate amounts and timely manner. Plant growth regulator treatment was expected to increase cutting's survival rate and rooting percentage. Objective of this research was to determine the effect of plant growth regulator on the growth of shoot and stem cutting of Duabanga moluccana. This research would be useful to provide information for the production for high quality seedlings. MATERIAL AND METHOD This research was carried out on green house with KOFFCO system (Komatsu-Forda Fog Cooling System) at Balai Penelitian dan Pengembangan Hutan dan Konservasi Alam, Gunung Batu, Bogor, West Java. from August to october 2010. Materials used in this research were shoot and stem of Duabanga seedlings from selected mother trees (M07) from SEAMEO BIOTROP, Rootone-F, Dithane M-45, rice husk, cocopeat, and zeolite. The experimental design in this research was completely randomized design with 2 factors and 3 replicates. The first factor was source of cutting material (shoot and stem) and the second factor was concentration of plant growth regulator (0 ppm, 500 ppm, 1000 ppm, and 1500 ppm). Growth parameters observed were (1) survival rate, (2) rooting percentage, (3) number of roots, (4) root length, (5) root fresh weight and dry weight (6) shoot fresh weight and dry weight (7) shoot-root ratio. Data was processed with analysis of variance then followed by fisher's LSD test. RESULT AND CONCLUSION Analysis of variance was conducted to explore the impact of all factors on growth parameters, shoot cutting was found to be the most significantly different related to each growth parameters observed; those were (1) survival rate, (2) rooting percentage, (3) number of roots, (4) root length, (5) root fresh weight and dry weight (6) shoot fresh weight and dry weight (7) shoot-root ratio , beside that, stem cuttings was not significantly different related to those growth parameters observed. Rooting percentage on shoot cuttings was 82% and stem cuttings was 0%. Plant growth regulator treatments were not significantly affected cuttings, because control (0 ppm) on shoot cuttings showed high rooting percentage value (77%), followed by 500 ppm (80%), 1500 ppm (83%), and 1000 ppm (87%). Interaction between source of materials and concentration of plant growth regulators was also not significantly related on each growth parameters observed because all of stem cutting could not survive during root primordial initiation, shoot cuttings was also not significantly different related to those growth parameters observed, because control (0 ppm) on shoot cuttings produced significant survival rate (77 %).
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Judul: Best Difference Equation Aproximation to Duffing 's Equation
Abstrak: Persamaan Duffing merupakan persamaan yang sering muncul sebagai model masalah sistem ayun mekanis atau pada masalah rangkaian listrik. Umumnya penyelesaian persamaan ini secara numerik memberikan hampiran dengan gala! yang tinggi, seperti dengan metode Runge-Kutta. Tulisan ini mengkonstruksi suatu persamaan beda untuk menghampiri persamaan Duffing tersebut. Penyelesaian dari persamaan beda ini melibatkan fungsi-fungsi eliptik Jacobi. Berdasarkan penyelesaian ini diperoleh basil bahwa penyelesaian hampirannya persis sama dengan penyelesaian analitiknya. Penyelesaian analitik yang diperolehjuga melibalkan fungsi-fungsi eliptik Jacobi.
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