Judul: Identifikasi dan Karakterisasi Gen Toleran Genangan Populasi Padi BC4F1 Ciherang-Sub1
Abstrak: Submergence stress is one of the inhibitor factor at rice productivity. Therefore, in order to improve food security, the rice of submergence-tolerant need to be developed. Introduction of gene related to submergence-tolerant (Sub1) was done by site-directed crossing between Ciherang rice as host with rice IR64-Sub1 and Swarna-Sub1 as Sub1 donor. The aim of this study was to identify and characterize BC4F1 Ciherang-Sub1 that resulted from backcross between BC3F1 Ciherang-Sub1 and Ciherang. The existence of Sub1 gene was detected by using PCR analysis based on molecular marker that concerned Sub1 gene. Stages of research was started from planting of BC4F1 Ciherang-Sub1 seed, testing of submergence tolerance, isolation of rice DNA, measuring of concentration and purity of rice DNA, and PCR analysis with AEX1 and RM219 markers. The test results of the submergence showed that 15 plants of BC4F1 Ciherang/Swarna-Sub1 and 21 BC4F1 Ciherang/IR64-Sub1. PCR results with markers AEX1R and AEX1F showed that the DNA band sized 231 bp, while the results of PCR with the combined markers AEX1R and RM219F can distinguish heterozygote between Ciherang rice, Swarna-Sub1 and IR64-Sub1.
Keyword: Padi BC4F1, padi IR64-Sub1

Judul: Aplikasi PCR berbasis marka sub1 (AEX1 dan RM219) pada seleksi padi BC1F1 Ciherang-Sub1
Abstrak: Submergence stress is the third most important limitation to rice production from 42 biotic and abiotic stresses. FR13A has adapted to excessive flooding environment by submergence tolerance is controlled by a single major quantitative trait locus (QTL) on chromosome 9, named Sub1. However, these varieties are susceptible to diseases and insect pests. It is therefore an attractive research proposition to transfer Sub1 gene from traditional cultivars into more productive varieties. In this study, the Ciherang was used as host, and F1 Ciherang-Sub1 was used as donors Sub1. The purpose of this study were to generate BC1F1 Ciherang-Sub1 varieties from backcross between F1 Ciherang-Sub1 and Ciherang by site-directed crossing methods. Selection of BC1F1 was done by submergence test and PCR analysis based Sub1 marker. BC1F1 Ciherang-Sub1 was succed in producing and contain Sub1 gene are obtained 16 BC1F1 Ciherang/Swarna-Sub1 and 22 BC1F1 Ciherang/IR64-Sub1 plants. Results of PCR amplification based AEX1 showed DNA band for Sub1A gene at 231 bp. The rices were containing DNA band belong to submergence tolerance rices. RM219 marker could distinguished between Ciherang, Sub1 donors, and BC1F1 Ciherang-Sub1 with DNA fragment at 204 bp and 194 bp. However, the different is too small, it is ranges of 5-10 bp until difficult to determine clearly heterozygous of BC1F1 Ciherang-Sub1.
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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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