Judul: Analysis of somatic embryogenesis of oil palm (Elaeis guineensis Jacq.) using temporary immersion system.
Abstrak: Micropropagation of oil palm through somatic emrbyogenesis is still not efficient because low percentage of somatic embryo formation and germinating somatic embryo. The objectives of these research are to obtain the best of (i) liquid medium used in shaker technique, (ii) medium and immersion time in Temporary Immersion System (TIS), (iii) to identify the marker of embryogenic callus with Scanning Electron Microscope (SEM) and (iv) to identify genetic changing in vitro (off-type) from 14 months of somatic embryo with Simple Sequence Repeats (SSR). The planting materials were embryogenic callus of embryoid-lines S15.355 and S82.132. Two types of medium consisted of MSK and MSD were tested in shaker technique, with the addition of several vitamines and combination of 0; 0.3; 0.6; 0.9 mg/L 2,4-D with 0; 4.0; 8.0 mg/L NAA. Medium MSD0 and MSD2 were used in TIS with every 1, 3, and 6 hours of immersion time and immersed in 3 minutes. Analysis marker for embryogenic and non embryogenic callus conducted by SEM and molecular marker by 20 microsatellite primers. The results showed that medium MSD2 is the best for increasing the proliferation of embryogenic callus and enlarging the somatic embryo of oil palm. Besides, types of genotypes gave different proliferation rate in diferrent medium composition and immersion time. The immersion time of 1, 3, and 6 hour showed no significant difference in increasing rate of embryogenic callus fresh weight for embryoid-line S15.355 and S82.132, respectively. Embryogenic callus analysed by SEM showed that embryogenic callus had smoother and lighter surfaces compared with non embryogenic callus. The result of SSR analysis showed that only 10 primers gave polimorphic bands and the others gave monomorphic. There was no genetic changing in vitro (off-type) from 14 months of samples.
Keyword: Elaeis guineensis, Elaeis guineensis, Temporary Immersion System, microsatellite marker, somatic embryogenesis, Scanning Electron Microscope

Judul: Keefektifan embriogenesis in vitro kelapa sawit (Elaeis guineensis Jacq. var. Tenera) dari eksplan daun muda, embrio zigotik matang dan bunga betina immature
Abstrak: Oil palm (Elaeis guineensis Jacq.) is an important commercial crop for all the producer countries. It is the world‟s leading vegetable oil crop. In the last decade, the interest in palm oil as biofuel was eventually caused constraints on worldwide supply for edible palm oil. In addition, low production and lack of conventional seeds and seedlings are always observed from the potential producer countries. More than one hundred million of tissue culture plantlets are needed per year. Indonesia is the largest world producer country with about 23 million tons of palm oil per year. The study was carried out to find in short term the optimum medium for callus induction and somatic embryo formation from young leaves, mature zygotic embryo and immature female flower explants of oil palm (E.guineensis Jacq.) var.Tenera. Three different independent experiments related to explant sources of oil palm (Elaeis guineensis Jacq.) var. Tenera include young leaf, mature zygotic embryo and immature female flower explants isolated from 9 and 13 years old trees were investigated on somatic embryos production. These explants were inoculated onto solid modified MS and Eeuwens basal medium containing 107.41μM NAA and associated with 0, 22.62, 45.24 or 67.86 μM 2,4-D and onto another MS basal medium with high concentration 450μM picloram or 450 μM 2,4-D in the presence of 0,03% (w/v) activated charcoal to induce embryogenic calli. The percentage of oxidation was ranged from 25 to 100% for leaf explant and from 0 to 46.67% for zygotic embryo explant, while it was 100% for female flower explant. The level of contamination was varied from 1.11 to 100 % for leaf explant, from 0 to 35.56% for zygotic embryo explant, and 8.33 to 41.67% for female flower explant. After 28 weeks of culture, compact and pearly-white, globular callus was obtained from the leaf number five (L5). The media 2,4-D and NAA concentration (67.86 and 107.41μM) respectively combination was the optimal media for embryogenic callus induction, while the media containing only NAA (107.41μM) induced the highest percentage of calli formation (30.56%). After 36 weeks of culture, direct embryoids was obtained from leaf number six (L6) onto the media containing the combination of NAA (107.41μM) and 2,4-D (45.24 μM). According to zygotic embryo explant, the best result (7.90%) of embryogenic callus was achieved onto Eeuwens media containing NAA (107.41μM) after 28 weeks. Highest percentage (38.33%) of direct shoot development was also obtained from the same media NAA (107.41μM). For female flower explant no callogenesis was observed during the study period. After 4 subsequent subcultures onto the same medium with gradually reduction of auxin concentration, the embryogenic callus and embryoid cells from young leaves and mature zygotic embryo explants, failed to develop during the time require for this study.
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Judul: Closed Knight’s Tour pada Papan Catur Berbentuk Persegi Panjang dengan Ukuran Maksimal 8 × 8
Abstrak: Closed Knight’s Tour merupakan langkah kuda yang mengunjungi setiap kotak pada papan catur tepat satu kali dengan langkah kuda berawal dan berakhir pada kotak yang sama. Graf yang terbentuk dari closed knight’s tour dinotasikan sebagai graf G(m,n), dengan m adalah banyaknya baris dan n adalah banyaknya kolom. Graf tersebut memuat Hamiltonian cycle. Sebuah graf terhubung G adalah graf bipartite jika dan hanya jika graf tersebut tidak memiliki cycle dengan panjang ganjil. Papan catur yang memenuhi syarat cukup untuk memiliki closed knight’s tour adalah papan catur berukuran 5 × 6, 5 × 8, 6 × 6, 6 × 7, 6 × 8, 7 × 8, dan 8 × 8.
Keyword: bipartite, closed knight’s tour, hamiltonian cycle, knight’s tour, teori graf