Judul: Uji Antagonisme antara Trichoderma spp. dan Fusarium oxysporum pada berbagai pH Medium In vitro
Abstrak: Penelitian ini bertujuan untuk menginventarisasi jenis-jenis Trichoderma di beberapa lokasi pertanaman buncis (Phaseolus vulgaris). Di samping itu juga untuk mengetahui isolat Trichoderma yang menyebabkan persentase hambatan tertinggi terhadap Fusarium oxysporum yang diisolasi dari tanaman buncis pada berbagai pH medium agar. Pengambilan contoh tanah dilakukan di daerah pertanaman yang sedang atau sehabis ditanami buncis. Pada setiap petak diambil 5 contoh tanah secara acak, kemudian dikeringudarakan dan disaring dengan saringan 9 mesh. Untuk mengisolasi Trichoderma dari contoh tanah digunakan metode pengenceran. Setelah itu setiap koloni Trichoderma yang berbeda warna dan pola pertumbuhan dari setiap pengenceran yang memberikan koloni cendawan secara terpisah dan dari setiap lokasi dimurnikan pada medium Potato Dextrose Agar (PDA). Kemudian untuk mengidentifikasi cendawan digunakan medium Malt Extract Agar (MEA). ...
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Judul: Identifikasi Molekuler Trichoderma spp. dan Aktivitas Antagonisnya terhadap Fusarium oxysporum f.sp cubense
Abstrak: Trichoderma is a cosmopolitan fungus that widespread in the soil and rotten wood. Various species of Trichoderma have been used, as a producer of enzymes and other metabolites or as a biocontrol agent. Therefore, identification of Trichoderma strains become important. Until now, many identity culture Trichoderma in Indonesia have doubtful validity. Trichoderma concept changed from time to time. Significant efforts in formulating the concept of Trichoderma was first performed by Rifai in 1969 based approach to morphological characters. Trichoderma species are divided into 9 aggregates, namely T. piluliferum, T. polysporum, T. hamatum, T. koningii, T. aureoviride, T. harzianum, T. longibrachiatum, T. pseudokoningii, and T. viride. This concept was later revised by Bissett in 1991 with the introduction of section 5 (section) is section Trichoderma, section Longibrachiatum, section Saturnisporum, section Pachybasium, and section Hypocreanum. Along with the development of methods of DNA extraction and phylogenetic analysis of the fungus, identification of Trichoderma species have been changed from morfohology in to combination of morphology and phylogenetic analysis. The first, phylogenetic analysis approach of Trichoderma by Kindermann in 1998 using DNA sequence analysis of the ITS region to 85 strains of Trichoderma. Then, when the approach of a single gene can not be relied upon to distinguish some species that are morphologically similar, multigene analysis was able to distinguish the species. At this time locus used in phylogenetic analysis and species identification in Trichoderma has been established that, ITS, tef α-1, RPB2, and Endokitinase. Trichoderma research in Indonesia have been carried out, but only a few research that include diversity and taxonomic studies. Trichoderma diversity and taxonomic studies from Indonesia is important because it can serve as a model for other fungal diversity studies. Therefore, this study aims to identify the 27 accession numbers Trichoderma collection of LIPIMC and IPBCC derived from litter and soil in Indonesia through a variety of phylogenetic approaches two genes (ITS and tef α-1). In addition, this research also aimed to characterize the antagonistic activity of Trichoderma spp. against Fusarium oxysporum f.sp. cubense (Foc), causes Fusarium wilt disease in bananas, because of the demands of the community to develop a biocontrol Foc agent. Identification of Trichoderma started early stages by performing morphological characterization. Colonies character observed in 5 days that were incubated at room conditions. After that, the microscopic preparations were made by using the method of Riddle and preparations were observed under a microscope Olympus BX53. Colony characters and microscopic characters are recorded as a material for morphological identification. Molecular phylogenetic analysis was started by growing Trichoderma isolates on media Potato Dextrose Broth (PDB) and incubated at 27˚C for 3-5 days. DNA extraction using PhythopureTM DNA Extraction Kit (GE Healthcare, UK), and then proceed with the ITS region amplification primer pair ITS4 (5'-TC CTCCGCTTATATATGC-3') and ITS5 (5'-GGAAGTAAAAGTCGTAACAA GG-3'), and α tef -1 (translation elongation factor-1 α) with primer tef1-fw (5'-GT GAGCGTGGTATCACCATCG-3 ') and tef1-rev (5'-GCCATCCTTGGAGACC AGC-3'). DNA sequencing is done by sending the product to FirstBASE (Malaysia). DNA sequences were analyzed by PCR using the MEGA program (Molecular Evolution and Genetic Analysis) version 5.05. On this analysis, kinship was
Keyword: biocontrol, Fusarium oxysporum f.sp cubense, phylogenetics, taxonomy, Trichoderma

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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