Judul: Abnormality of flowers and fruits in oil palm (Elaeis guineensis Jacq) clones based on of morphology, biochemistry and genomic analysis.
Abstrak: Phenomena of abnormal flowers found was around 0-17% among clones of oil palm, that reduce productivity. Previous research showed that abnormality of flower is related to DNA hipomethylation in calli and leaves tissues of the abnormality plant. The changes of DNA methylation correlates with gen expression in the specific tissue. In the case of oil palm abnormalities occur in flower and fruit tissues. The objectives of this research were to characterize the morphology of flower and fruit, to determine the oil content in relation to malonyl-CoA and asetyl-CoA, to study changes of DNA methylation status and genomic DNA changes related with flower and fruit abnormality. Eighty plants used in this research consisted of three clones, i.e MK152, MK 176, and MK 209. These were obtained from the collection of ”Badan Pengkajian dan Penerapan Teknologi (BPPT) Ciampea”. Characterization of plant morphology was conducted visually, whereas the oil content of mesocarp was analyzed by extracting the oil with soxhlet system, determination of the malonylCoA and acetyl-CoA content by HPLC (High Performance Liquid Chromathography), the quantification of cytosine methylation by performance RP-HPLC, and detection of alteration of the DNA genome was analysed by RAPD technique (Random Amplified Polymorphic DNA). The results showed that abnormalities of female and male flowers as well as fruits were found in tissue culture-derived plants. The rudimentary stamen in the female flower, and stamen of the male flowers were transformed into carpel-like structure. Fruit abnormality was catagorized into five classes, i.e normal, light abnormal (AbR), heavy abnormal (AbB) and two types of severe abnormal, AbSB1 and AbSB2. The content of palm oil in immmature fruit from the three type of fruits (normal, AbR and AbB) were similar. The normal fruit contained around 74.66 -77.26%, AbR 77.47-80.85%, and AbB 73.89-78.62%. The high palm oil content in the normal (MK 152), AbR (MK 209), and AbB (MK 176) were related to higher malonyl-CoA (0.069 0.085, dan 0.068 mg/ml respectively) than the acetyl-CoA (0.036, 0.021 dan 0.023 mg/ml respectively). On the contrary in the severe abnormal fruits, the acetyl-CoA was higher (0.066-0.087 mg/ml) and the malonyl-CoA lower (0.022-0.037 mg/ml). Compared to the normal plant, hypomethylation in leaves tissue was 1.31-4.01% and hypermethylation was 0.69-2.66% in flowers tissue of the abnormal plants. However, changes of DNA methylation status was not found in fruits tissue. Changes of the sequence of DNA genome in the plants within the same clone were detected using five random primers, i.e.OPC-08,OPD-15, W-15, OPC-09 and SC10-19. A band DNA of the normal plant was detected by OPC-08. Changes of the methylation status in leaf and flower tissues was not directly related to the abnormality of the oil palm flowers. The difference of DNA bands were found among plants of the MK 152.
Keyword: oil mesocarp, malonyl-CoA, methylation cytosine, DNA sequence, West Java

Judul: Correlation between DNA methylation and expression of the MADS-box genes on mantled fruit of oil palm (Elaeis guineensis Jacq.) clonal plants.
Abstrak: The presence of abnormal mantled fruit on large scale clonal production of oil palm had trully affected the oil productivity. Mantled phenotype is likely to be that of an epigenetic change involving DNA methylation and the MADS-box transcription factor genes which encoded floral organ homeotic transformation. We developed an Ultra Performance Liquid Chromatography (UPLC) to quantify the degree of methylation related to fruit abnormality and Quantitative Real-Time PCR (qPCR) to know the correlation between the expression of the MADS-box genes with mantled fruit abnormality. This study were consist of two experiments, the DNA methylation analysis and the MADS-box genes expression analysis. Materials used in this study were the young fruit of both normal and mantled with very heavy type of abnormality. Abnormal mantled fruit were grouped into two types, one is taken from inside (Abn m) and other is from outside the bunch (Abn). In gene expression analysis, cDNA used as the template for qPCR were obtained from the reverse transcription of the mRNA, while methylation analysis performed on total DNA genomic. The research for each gene and cDNA were conducted in two replications. The expression of the target genes were compared to EF1-α1 as the reference gene. Based on qPCR efficiency by comparing the target genes with the reference gene, from 11 genes that have been tested, i.e EgSQUA1, EgSQUA3, EgFUL, EgGLO1, EgGLO2, EgDEF1, EgAG2, EgAGA, EgAGL6, EgF-box and EgRING, only three genes are qualified for qPCR analysis, i.e EgAG2, EgAGA and EgAGL6. EgAG2 expression was not different in both mantled and normal fruit, while EgAGA expression was higher in mantled and EgAGL6 expression was significantly lower in outside-bunched mantled fruit (Abn). Nuclease S1 digestion and UPLC revealed the genome-wide increasing in DNA methylation on mantled fruit (18.33-19.55%) compared to its normal counterparts (5.67%). This increased in global DNA methylation showed by the significant decreased in EgAGL6 transcript level on mantled fruit. This gene is assumed to be involved in the development of mantled fruit.
Keyword: DNA methylation, MADS-box genes, mantled fruit, quantitative real-time PCR.

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