Judul: Deteksi dan identifikasi fitoplasma yang berasosiasi dengan penyakit layu kelapa di Pulau Derawan Kalimantan Timur
Abstrak: Coconut as a main commodity in Derawan Island has two functions, i.e. farmer’s income source and beach plant aesthetics. The occurrence of coconut wilt disease resulted in eradication of about 10% of the palm in 2010. The objectives of this study were: (1) to describe morphological and histopathological symptoms of coconut wilt disease in Derawan island, (2) to detect the presence of phytoplasmas associated with coconut wilt disease in Derawan island using nested-PCR (n-PCR) technique, (3) to identify and classify phytoplasmas associated with coconut wilt disease based on 16S rRNA gene sequences, (4) to detect the presence of phytoplasmas from leafhoppers (Hemiptera: Cicadellidae) and love vein (Cassytha filiformis) (Laurales: Lauraceae), which expected to have ability to transmit the pathogen. The methods in this research included visual and microscopic observation, detection of phytoplasmas with n-PCR method, cloning of the nPCR products, sequencing, analysis of sequencing results using BLAST, construction of phylogenetic tree, and in silico RFLP analysis. The results showed that the suspected phytoplasmas reside in phloem tissues and were detected with both microscopic and molecular techniques. Phytoplasmas associated with coconut wilt disease in Derawan island belong to 16SrII (witches’ broom phytoplasma) and 16SrXI (Ca. Phytoplasma oryzae) groups. The use of nPCR employing R16F2n/R16R2 primer pair with expected amplicon at size of about 1.25 kb are positive not only for particular strain of phytoplasmas but also other bacterial species that mainly belong to Gram Positive group. Phytoplasmas that belong to 16SrII are also detected in some leafhoppers and C. filliformis.
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Judul: Comparative Genomics and Phylogenetic Analysis of Indonesian Coconuts with Other Important Palms Species Based on Chloroplast Genome
Abstrak: Kelapa adalah salah satu spesies terpenting secara ekonomi dari famili Arecaceae. Kelapa unik yang memiliki endosperm remah, lembut, dan terlepas dari batok kelapa akibat dari mutasi alami yang dikenal secara lokal di Indonesia sebagai kelapa kopyor. Penelitian ini mencakup karakterisasi genom kloroplas kelapa kopyor varietas (var.) Genjah Hijau dan analisis komparatif genomik antar spesies palma lainnya. Berdasarkan analisis sekuens, genom kloroplas kelapa var. Genjah Hijau Kopyor memiliki panjang 158 462 bp dan memiliki struktur kuadripartit yang terdiri dari satu daerah large single-copy (LSC; 86 198 bp), satu daerah small single-copy (SSC; 17 712 bp) dan dua daerah inverted repeat yang identik (IR; 27 276 bp). Genom terdiri dari 116 gen. Analisis komparatif menunjukkan bahwa daerah pengkode protein lebih terkonservasi dibandingkan dengan daerah non-pengkode protein. Analisis filogenetik menunjukkan bahwa kelapa memiliki hubungan yang erat dengan Phoenix dactylifera. Karakterisasi genom ini ddapat memberikan informasi untuk mengembangkan penanda spesifik gen, pemetaan genom kloroplas, program pemuliaan tanaman, studi evolusi, dan konservasi kelapa kopyor., Coconut is one of the most economically important trees of family Arecaceae. This unique coconut has curd, fluffy, and crumbly endosperm because of natural mutation that is locally known in Indonesia as kopyor coconut. This research encompasses the characteristics of kopyor coconut var. Green Dwarf chloroplast genome and comparative genomics between other palm species. Based on sequence analyses, the chloroplast genome of kopyor coconut var. Green Dwarf was 158 462 bp in length and it had a typical quadripartite structure composed of a large single-copy (LSC; 86 198 bp), a small single-copy (SSC;17 712 bp) and two identical inverted repeat (IR; 27 276 bp). The genome consisted of 116 genes. Comparative analysis showed that the coding regions are more conserved than non-coding regions. The phylogenetic analysis showed that the coconut had a closed relationship with the Phoenix dactylifera. These genome characterizations could provide information to develop gene-specific markers, chloroplast genome mapping, plant breeding program, evolutionary study, and conservation of kopyor coconut.
Keyword: anotasi, genom kloroplas, kopyor, komparatif genomik

Judul: Analysis of M/G/1 Queue Model with Two Phases of Service and Bernoulli Feedback System
Abstrak: Model antrean M/G/1 dengan sistem feedback Bernoulli adalah model antrean dengan proses kedatangan mengikuti proses Poisson. Pada karya ilmiah ini dibahas sistem antrean M/G/1 dengan dua fase layanan. Setelah layanan pertama selesai, pelanggan dapat memilih untuk meninggalkan sistem dengan peluang ... dst, The M/G/1 queueing model with the Bernoulli feedback system is a queueing model with the arrival process following the Poisson process. In this manuscript M/G/1 queueing system with two phases of service is discussed. After the first service is completed, the customer can choose to leave the system with probability ... dst
Keyword: queue, Bernoulli, probability generating function, expected value