Judul: Kemampuan Bakteri Endofit Penghasil Asam Indol Asetat dan Pengaruhnya dalam Mengendalikan Virus Gemini pada Tanaman Cabai (Capsicum annum L.)
Abstrak: Production of red chilli in Indonesia decreased because of gemini virus disease. The disease is transmitted by Bemisia tabacias insect vector. One of possibility methods is to improve plant resistancecan be supported byendhopytic bacteria or Plant Growth Promoting Rhizobacteria (PGPR) which can produce IAA (Indole Asetic Acid) hormone. IAA hormone can serves as a growth promoter and plant resistance. The aims of this research are to test the effect of 50 isolates endhopytic bacteria producing hormones in the IAA and analyze the effect on growth of chilli plants that Gemini virus. The experimental design was factorial randomize complete block design which three AIA treatment and two variety of chilli treatments as factors. These treatments were replicated in five blocks. The results showed that infection by Gemini virus could reduce and increase plant growth.
Keyword: Gemini virus, productivity, Plant Growth Promoting Rhizobacteria, endophytic bacteria, chilli, hormone

Judul: Keefektifan Cendawan Endofit untuk Menekan Infeksi Chilli veinal mottle virus pada Tanaman Cabai (Capsicum annuum L.)
Abstrak: Chillipepper is an important horticultural commodity in Indonesia because of it’s economics and consumption value. Infection of Chilli veinal mottle virus (ChiVMV) is a constraint to chillipepper production. This research is conducted to evaluate the potency of 3 isolates of endophytic fungi (H1, H5, and H12) to suppress ChiVMV infection and to improve growth of chillipepper. The endophytyic fungi was applied through seed treatment and leaf spray on chillipepper variety TM88. Virus inoculation was done mechanically and virus detection was conducted using Double Antibody Sandwich ELISA (DAS ELISA). Experiment was conducted using randomized complete design with 4 treatments of endophytic fungi i.e. fungi isolate H1, H5, aH12, and without endophytic fungi each with 3 replication. Observation was made for disease incidence, plant height, and root volume. Data analysis was conducted using ANOVA followed by Duncan test at 5%. ELISA absorbance value indicated that treatment of endophytic fungi (H1, H5, and H12) can suppress ChiVMV, although the disease incidence is still high. Endophytic fungi isolate H5 tends to improve plant growth showed by its potency to increase plant height up to 4 weeks after planting.
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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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