Judul: Induction of haploid callus through anther cultured on citrus sp.
Abstrak: Anther culture is one method to produce haploid callus and plants. By the doubling of their chromosome, double haploid plants can be generated and used to produce F1 hybrids. Haploid callus can also be used as tissues for somatic hybriditation to produce triploid Citrus and other non-conventional breeding program. The objective of this research were to study microspore development of four Citrus spesies (Tangerine Garut, Tangerine Batu 55, Siam and Pamelo), effect of cold pretreatment, media type, and plant growth regulator on of callus induction from citrus anther. The development of microspores can be seen by measuring the ratio of the size of the sepals and petals flower. Microspores that have high percentage of uninukleat given different levels cold pretreatment to improve the ability to form callus. After treated with cold pretreatment, callus was induced with various formulations of media, resulting haploid callus then carried out chromosome counting. The results shown that the microspore uninucleat was highest (78,2% to 91,4%) in medium-size flowers with a ratio of the sepal: petal (1:4 - 2:6) mm in flower Tangerine Garut, Tangerine Batu 55, Siam Citrus, and (6:14 - 6:17) mm in flower Pamelo. Microspores uninucleat in Garut citrus flowers ranged from 78.2 to 91.4%, at tangerine Batu 55 flowers ranged from 78.2 to 85.6%, the citrus flower Siam from 79.4 to 90.5%, and citrus flower Pamelo ranged from 78.2 to 85.4% of the take total microspores. Cold pretreatment of anther for 5 days was able to inducted callus citrus keprok Garut up to 2%. MT medium + 3 mg / l BAP + 500 mg / l extract malt on solid media were able to induce callus 14.5% in tangerine Batu 55, while the treatment of liquid media is only able to induce callus up to 4.5%, and solid + liquid media treatments able to induce callus 3.6%. The data is observed when the culture aged 6 weeks after planting. The best medium to induce callus Siam Citrus are MT medium + 3 mg / l 2,4-D + 500 mg / l extract malt, is able to induce callus up to 1,6%. MT medium with 3 mg/l BAP and with 1 mg/l NAA was able to induce callus Pamelo up to 2,6%. Chromosome counting is performed to determine ploidy level of callus produced. The result showed that all chromosome of the anther derived callus was 9 as half of diploid chromosome.
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Judul: Interspecies protoplasts fusion between citrus siam simadu (Citrus nobilis Lour.) and citrus mandarin satsuma (C. unshiu Marc.)
Abstrak: Somatic hybridization is an important tool for supplying new varieties to be used directly as cultivar genetic improvement programs. In citrus, this technology has been extensively used and has many important implipications. The objectives to the research are produceed citrus somatic hybrids between citrus siam Simadu and Mandarin Satsuma with chemical fusion (PEG). Protoplasts of siam Simadu from calli with Mandarin Satsuma from mesophyll-derived protoplasts were regenerated by somatic embryogenesis. Concentration and duration of incubation in a solution of PEG strongly affected the fusion induction of siam Simadu with Mandarin Satsuma. High concentrations of PEG can increase the frequency of fusion, while the low concentration produces a low frequency of fusion. The result showed that protoplasts from embryogenic callus of Simadu tangerine and in vitro leaf of Mandarin Satsuma can be isolated in large numbers by using a combination of cellulase Onozuka R10, Yakult Yakult% 1% with R10 Maserozim in CPW solution. Protoplasts are purified with a mixture of 25% sucrose with 13% mannitol. Protoplast density produced from embryogenic callus is 15.7x105 protoplasts / g callus and 13x105 protoplasts/ g in vitro leaf. The concentration of PEG used to induce fusion between mesophyll protoplasts Mandarin Satsuma and siam Simadu callus affect the average number of protoplasts fusion. Average number of protoplasts were fused by using PEG 4% are 3.3 hetero fusion, 5.0 homo fusion and multi-fusion. Average number of protoplasts were fused by using PEG 30% are 4.7 hetero fusion, 6.7 homo fusion 6.7 and 7.7multi-fusion. The success of fusan regeneration on regeneration medium is influenced by PEG concentration used for induction of fusion. Protoplasts were fused with PEG only 4%, which can regenerate to form cell walls, making cell division, colony cells, micro-callus and somatic embryo. Protoplasts were fused with PEG 30% can only be regenerated to form the cell wall and cell division. Giving light to the culture after 2 weeks may accelerate cell division that can form colonies of cells. Dilutions of cell suspension with the same medium (without 2, 4-D) can accelerate the growth and development of the protoplasts formed colonies of cells, micro-callus and somatic embryos. MW medium is best used in the fusion because it can encourage of somatic embryos directly. Addition of ABA 0.5 mg / l in the media can produce somatic embryos and GA3 0.5 mg / l can germinate mature somatic embryos to plantlets with 76% germination efficiency. Somatic hybrids were germinated, then trasfered to a medium culture, and finally grafted in greenhouse. The hybrids were confirmed by growth of in vitro culture, morphology, cytology (chromosome number), molecular analysis (ISSR), and contain of chlorophyl Keywords: Citrus, male sterility, chemical fusion, somatic embryogenesis, morphology,
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Judul: igenvalues and Eigenvectors of Tridiagonal Matrix with Non Constant and Recurrent Diagonal Entries.
Abstrak: Matriks tridiagonal adalah suatu matriks yang mempunyai entri-entri bernilai nol kecuali pada diagonal utama, di bawah diagonal utama (subdiagonal) dan di atas diagonal utama (superdiagonal). Entri pada diagonal utama tidak konstan dan berulang. Setiap entri pada matriks tridiagonal ini adalah bilangan kompleks. Dalam karya ilmiah ini, akan dibuktikan 3 teorema untuk menentukan nilai eigen dengan 2 kasus dan 1 teorema untuk menentukan vektor eigen. Teorema pertama menentukan polinomial karakteristik dari matriks tridiagonal. Polinomial karakteristik dari matriks tridiagonal tersebut digunakan untuk menentukan nilai eigen pada teorema kedua dan ketiga serta menentukan vektor eigen pada teorema keempat
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