Judul: Pengaruh media simpan, ruang simpan dan lama penyimpanan propagul terhadap viabilitas benih Rhizophora apiculata
Abstrak: Kondisi hutan mangrove di Indonesia yang semakin rusak membutuhkan usaha rehabilitasi. Untuk kegiatan penanaman berskala besar seringkali benih harus didatangkan dari daerah lain yang membutuhkan waktu yang cukup lama untuk transportasinya. Pengiriman bibit dalam bentuk semai sangat tidak efisien sehingga perlu dikembangkan metode pengiriman bibit dalam bentuk propagul. Masalah yang timbul adalah karena propagul R. apiculata merupakan benih rekalsitran sehingga pada kadar air tertentu yang relatif tinggi maka benih cenderung mudah untuk berakar dan bila kadar air rendah maka benih mati atau viabilitasnya menurun. Tujuan penelitian ini adalah untuk mengetahui pengaruh ruang simpan. media simpan dan lama penyimpanan terhadap viabilitas benih R. apiculata. Penelitian dilaksanakan di rumah kaca Balai Teknologi Perbenihan Kehutanan dan Perkebunan. Ciheuleut Bogor selama empat bulan yaitu mulai akhir Januari sampai akhir Mei 2000. Prosedur kerja penelitian ini terdiri dari tahap persiapan (wadah simpan, ruang simpan, media simpan dan media perkecambahan). pengunduhan propagul, seleksi benih. penyimpanan benih. penyemaian, pemeliharaan dan pengambilan data. Adapun data yang diambil adalah Persentase Berakar (PB) benih selama periode simpan. kadar air benih (KA). daya berkecambah (DB). nilai perkecambahan (NP), kecepatan tumbuh (KT) dan nisbah pucuk akar (NPA) semai R. apiculata. Disamping itu sebagai data penunjang juga diukur kadar air media simpan. berat 1000 benih serta panjang rata-rata dan diameter rata-rata hipokotil. Rancangan percobaan yang digunakan dalam penelitian ini adalah rancangan acak lengkap (RAL) faktorial 5 x 2 x 2 dengan 3 kali ulangan. Adapun perincian faktor-faktomnya adalah sebagai berikut: Faktor A (lama penyimpanan ) terdiri dari a0 (0 minggu), at (1 minggu). a2 (2 minggu). a3 (3 minggu) dan a4 (4 minggu); faktor B (ruang simpan ) terdiri dari bl (ruang AC suhu 19"C- 20°C. RH: 60 %-61%) dan b2 (ruang kamar: suhu 26°C-28°C. RH: 80%-85%) dan faktor C (media simpan) terdiri dari cl (sabut kelapa: KA awal 61.41%) dan c2 (serbuk gergaji: KA awal 37.39%).
Keyword: Seed storage

Judul: Pengaruh media simpan, ruang simpan dan lama penyimpanan terhadap viabilitas Propagul Rhizophora mucronata
Abstrak: The potention of mangrove forests in Indonesia has been decreasing. Therefore, rehabilitation is necessary in order to maintain sustainability of forest ecosystems. One of the efforts is the replanting of mangrove forest. The success of planting depends on the availability of seed. Seeds can not be obtained any time if needed so that storage seed is necessary for seed viability can be maintained within a certain time period until the time of planting arrives. The problem has been arise because of Rhizophora mucronata is a recalcitrant seed, which is at certain moisture content that relatively high, the propagule tend to be easy to germinate and if the moisture content is low, the propagule will be die or loss of their viability. This study aims to investigate the influence of storage media, storage room and time of storage on propagules viability of Rhizophora mucronata and to compare the germination from the rapid test (cutting test) with the germination from the direct test. This study used a factorial experiment with completely randomized design (CRD) factorial 5x2x2 with 3 replicates. The details of the factors are: factor A (time of storage) consists of A0 (0 weeks), A1 (1 week), A2 (2 weeks), A3 (3 weeks), and A4 (4 weeks); factor B (storage room) consists of B1 (AC room) and B2 (living room); and factor C (storage media) consists of C1 (sawdust) and C2 (coconut husk). Working procedures of this study consist of the preparation phase (the container store, room storage, storage media and germination media), collecting of propagule, propagule selection, storage of propagule, propagule cutting test, seeding propagule, maintenance and retrieval of data. The data collected is the result of cutting test from propagule, the percentage of rooted propagule (PB), moisture content (MC), germination (DB), germination value (NP), the growth rates (KT), shoot and root ratio (NPA). Based on these results, the influence of interaction between storage time, storage room and storage media caused significant differences on germination propagule R. mucronata. The influence of interaction between storage time and storage room caused significant differences to the percent of rooted from propagule R. mucronata. The influence of storage time and storage media caused significant differences in seedling roots to shoot ratio of R. mucronata. In this study, coconut husk media storage that is placed in the air conditioner room capable to maintaining the viability of propagule R. mucronata until the time of storage for 4 weeks. The result of estimation methods viability propagule R. mucronata with cutting test is relatively similar with the directly propagul germination test results.
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Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
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