Judul: Studi fenologi pembungaan dan keragaman genetik menggunakan marka morfologi dan marka molekuler pada tanaman jarak kepyar (Ricinus communis L.)
Abstrak: This study was aimed at determining flowering phenology, characterizing and analyzing the diversity of phenotypes based on morphological and molecular markers (RAPD), to provide basis for the development of new varieties of castor (Ricinus communis L.) in Indonesia. The plant material for flowering phenology was PRO accession, and 14 castor accesions of IPB collection were used for genetic diversity study. The first leaf of the sprouts was sampled for DNA extraction then used in RAPD analysis. The eight primers used in this study were OPE-3, OPE-19, OPE-20, OPH-13, OPH-14, OPM-2, OPM-5, and OPM-8. The observation on flowering phenology showed that castor was a monocieous plant indicating a cross-pollinated species. The PRO had inflorescence type 1 (gradient monoecism) according to Shifriss in William (1967) in which female flowers were located at distal part and male flowers were at proximal part. Flowers are incomplete and imperfect. Female flowers (averaged of 20 flower/raceme) opened for 3-6 days followed by male flowers averaged f 52 flower/raceme for 1-2 days. Fruit set was 100%, and fruit development last about 40 days. Based on morphological markers of plant height, petiole length, leaf length and leaf width, 100 grain weight, grain length, grain width, and grain thickness, the 14 accessions were significantly diversed. Weight of 100 grains of seed characters were supposed to be for selection because its high heritability value and wide genetic variability coeficient (KKG). There were correlation between characters of width and length of leaves (97%), plant height and stem diameter (86%), petiole and leaf length (90%), as well as petiole length and leaf width (88%), and seed shape and mature petiole color (83%). At similarity coefficient of the morphological characters (qualitative) of 0.85, the 14 accessions were classified into 6 groups i.e. group 1 (BAG-1, PHIL-5, GRE, THAI-101, CIB-1, Sur, and PHIL-4), group 2 (plam-1, PHIL-2, and LAB-1), group 3 (PHIL-13), group 4 (PON-2), group 5 (PRO), and group 6 (TAN-1). Primers amplification produced 49 bands comprising of 36 polymorphic bands (73.47%) and 13 monomorphic bands (26.53%). At 0.85 coefficient of similarity of molecular characters, the 14 accessions were classified into 5 groups, i.e. group 1 (plam-1, PRO, GRE, CIB-1, LAB-1, BAG-1, PHIL-4, PHIL-5, and PON-2), group 2 (THAI-101 and TAN-1), group 3 (PHIL-13), group 4 (PHIL-2), and group 5 (Sur). Characters of juvenile stem color, juvenile petiole color, and mature stem color can be used as morphological markers, as well as OPH-14 primer can be used as molecular markers to classify accessions. PHIL-13 had the potential character to be used as germplasm in further plant breeding activities.
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Judul: Diversity among Indonesian Pulses based on Morphological and Molecular Markers (ISSR)
Abstrak: Pulses as one among the most common food consumed has a very high genetic diversity in Indonesia. The aims of this study were to determine genetic diversity of potential pulses, the relationships among pulses, and to characterise some pulses. The study was conducted at Pasir Kuda Experimental Station, Center for Tropical Horticulture Studies, Bogor from March 2016 to October 2016. The pulses were 6 accessions of winged bean (Psophocarphus tetragonolobus), 2 accessions of lima bean (Phaseolus lunatus L.), 2 accessions of egyptian bean (Lablab purpureus), 1 accessions of cowpea (Vigna sinensis), 1 accessions of long bean (Vigna unguiculata), 1 accessions of bambara groundnut (Vigna subterranean), 1 accession of jack bean (Canavalis ensiformis), and 1 accession of velvet bean (Mucuna pruriens). There were 45 morphological characters and 8 ISSR markers that were used in this study. Based on morphological analysis, qualitative characters showed 93,94% polymorphism among the pulses. All the quantitative characters showed significant different results. The cluster analysis showed two major groups at 0,594 of dissimilarity. Based on molecular analysis, the amplified bands are 100% polymorphic bands. The cluster analysis was devided into two major groups at 0,387 of dissimilarity. Accumulation between morphological and molecular markers has two major groups in the dendrogram at 0,437 of dissimilarity
Keyword: characterisation, clustering, legumes, microsatellites, potential crops

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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