Judul: Induksi Kalus Embriogenik dan Embrio Somatik Durian (Durio zibethinus Murr.) pada Berbagai Komposisi Media
Abstrak: Durian is a valuable tropical fruit. Durian agribusiness in Indonesia is still lags behind neighboring countries such as Thailand and Malaysia, whereas genetic, land and climatic resources for durian in Indonesia are better than those of other countries. Durian tissue culture can be applied for durian genetic improvement and mass propagation of elite varieties which finally can promote durian agribusiness in Indonesia. However, researches on durian tissue culture are still very limited. The objective of this study is to obtain the suitable type of explants, media, and plant growth regulator in embrogenic callus and somatic embryo induction of durian. The study was conducted in 2 successive trials. The first experiment was callus induction and the second trial was somatic embryogenesis induction of callus obtained from the first experiment. There were 4 type of explants used on callus induction experiment, namely flower receptacle, petal, endosperm and immature zygotic embryo of durian. Callus induction from flower receptacle and petal explants were arranged as a factorial two factors experiment. The first factor was durian genotype, namely Dramaga, Matahari and Simas, and the seond factor was 14 media composition which were composed of two types of basal media (MS and B5) and 7 level of plant growth regulator (PGR ), i.e., without PGR, 2, 4, 6 ppm of NAA and 2, 4, 6 ppm of picloram. Callus induction with endosperm and immature zygotic embryo explants using 1 genotype, viz. Otong. Experiments on endosperm explant was arranged as a factorial two factors experiment, that is benziladenin (BA) treatment (0 and 1 ppm) and thidiazuron (TDZ) treatment (0.0, 0:01, 0:05, 0.5 ppm) in the MS basal medium + B5 media vitamin with 100 ppm glutamine, 100 ppm asparagine, 500 ppm casein hydrolysate, and 0.5 ppm picloram. The treatments on callus induction from immature zygotic embryo explant were 5, 10, 15, and 20 ppm of picloram on MS basal medium. The second experiment was the induction of somatic embryogenesis of petal explants derived calluses by treatment with 0.0, 0.3, 0.5, 1.0, and 2.0 ppm BA on MS basal medium with B5 vitamin, 100 ppm glutamine, 100 ppm asparagine, 500 ppm casein hydrolysate, and 0.5 ppm picloram. The best medium composition on callus induction from flower receptacle explant was B5 basal medium with addition 2 ppm of NAA. The best one for petal explant was B5 basal medium with addition 2 ppm of picloram. Based on the result of percentage of explant producing calluses and callus emergence rate on petal and flower receptacle explants, it was indicated that Matahari variety was more responsive than Dramaga accession and Simas variety. The type of calluses derived from flower receptacle explant at the beginning of its emergence was watery friable callus (type 3 callus) which the cells were easily separated from one another. In one to two weeks after the callus emergence, this type of callus turned into a whitish to yellowish compact callus (type 1 callus) or pure white compact callus (type 2 callus). All three type of calluses, from morphological and histological observations, were supposed to be non-embryogenic ones. The type
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Judul: Induksi Embrio Globular pada Tanaman Aren (Arenga pinnata (Wurmb) Merr.)
Abstrak: Sugar palm is a monocot plant belong to the Arecaceae family economically valuable and have bright prospects to be developed for food products to bio-ethanol substituting fossil fuels. This plant is usually propagated generatively yet there are a few issues being faced such as a long reproductive cycle, long seed production and dormancy, low germination capacity, and uniform seedling growth. Non-conventional plant breeding through biotechnology is the best possible alternative solution to provide good quality seedlings in order to increase sugar palm productivity. Tissue culture through somatic embryogenesis method is a technique that can be used to induce abundant and relatively uniform somatic embryos from zygotic embryos. One of the key factors when using this method which is focused in this research is the role of plant growth regulators under the auxin, cytokinin, and gibberellin groups. The objective of this study was to get the best media to produce somatic embryos from zygotic embryos of sugar palm. The obtained results are expected to be used for future sugar palm non-conventional breeding. This research was conducted at Tissue Culture Laboratory Department of Agronomy and Horticulture, Faculty of Agriculture, Bogor Agricultural University from October 2012 to April 2013. It covers the embryogenic callus induction phase, globular embryo induction phase and globular embryos maturation phase. The first phase consisted six treatments with 2,4-D, NAA, and biotin combination aiming to induce callus formation from young zygotic embryos. In the second phase, callus obtained from the first phase were subcultured to 14 different treatments with various kinetin and TIBA combination. As for the third phase, explants which were obtained from the second phase were subcultured into media with or without GA3 combination. The variables which were observed were percentage and total sterile explants, percentage and total explants which induced callus formation, average percentage of callus coverage, percentage and total explants with base apocol smaller than haustorium, percentage and total pseudo roots, percentage and total explants which induced globular embryos, percentage and total alive and mature globular embryo clumps. Sterilization using NaOCl 1.575 % and alcohol 96 % was able to provide 50-85 % sterile explants. During callus induction phase, embryogenic callus were mostly formed at treatment A5 (MS + 3 mg l-1 2,4-D + 0.2 mg l-1 NAA + 100 mg l-1 biotin) which is 73.4 % after 8 weeks. All explants were able to form globular embryos on media B3 (callus A1 to media MS + 4 mg l-1 Kinetin), B6 (callus A1 to media MS + 1 mg l-1 Kinetin + 0.1 mg l-1 TIBA), B12 (callus A2 to media MS + 0.1 mg l-1 Kinetin + 1 mg l-1 TIBA), and B14 (callus A2 to media MS + 1 mg l-1 Kinetin + 1 mg l-1 TIBA) at 2 WAT during embryo globular induction phase. During embryo globular maturation phase, media C11 (globular embryo clumps B9 to media MS + 0.1 mg l-1 GA3) was able to induce 70.8 % mature globular embryo clumps.
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Judul: Approximation of the Median of Poisson Distribution Using the Relation of Poisson-Gamma Distribution
Abstrak: A major drawback of median is that median cannot usually be defined in closed form, even in the cases where their distribution functions are known. This study gives an approximation of the closed form for the median of the Poisson distribution by using the relation of Poisson-Gamma distribution. The approximation uses elementary techniques based on the monotonicity of certain sequences involving tail probabilities of the Poisson distribution and the Central Limit Theorem. Furthermore, a closed form expression for the mean absolute deviation 􀜧|􀜰􀰒 􀵆 􀜯􀝁􀝀􁈺􀜰􀰒􁈻| is also studied. The median is relevant because of the fact that it minimizes the mean absolute deviation of a Poisson random variable (􀜰􀰒􁈻 by considering median as central tendency.
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