Judul: Induction of Chemical Mutations of Monstera adansonii Plants with Streptomycin at Various Concentrations and Soaking Time
Abstrak: M. adansonii variegata merupakan salah satu jenis tanaman hias daun yang popular di masyarakat sejak pandemi Covid-19. Variegata adalah perbedaan warna dan corak dengan tanaman normal yang diperoleh dari mutasi. Mutasi pada M. adansonii dapat dilakukan dengan berbagai mutagen kimia salah satunya streptomycin. Penelitian ini bertujuan mengetahui kombinasi perlakuan konsentrasi dan lama perendaman streptomycin yang optimum untuk menghasilkan tanaman M. adansonii variegata. Penelitian ini dilaksanakan selama 4 bulan di Kebun Percobaan IPB Sukamantri menggunakan Rancangan Kelompok Lengkap Teracak (RKLT) satu faktor. Hasil penelitian menunjukkan bahwa kombinasi perlakuan streptomycin konsentrasi 750 ppm dengan lama perendaman 48 jam menunjukkan hasil yang paling baik di antara perlakuan lainnya dengan rata-rata persentase mutan putatif sebesar 73,33%. Hasil uji lanjut menunjukkan bahwa kombinasi perlakuan konsentrasi dan lama perendaman streptomycin paling optimum untuk menghasilkan M. adansonii variegata adalah konsentrasi 860 ppm dengan lama perendaman 81,64 jam. Kedua taraf tersebut tidak termasuk dalam taraf-taraf yang dilakukan dalam penelitian., Monstera adansonii variegated is one type of ornamental leaf plant that has been popular in the community since the Covid-19 pandemic. Variegate is the difference in color and pattern with normal plants obtained from mutations. Mutations in Monstera adansonii can be carried out with various chemical mutagens, one of which is streptomycin. This study aimed to determine the best combination of concentration and duration of soaking streptomycin to produce Monstera adansonii variegated plants. This research was carried out for 4 months at the Experimental Field of IPB Sukamantri using a factorial Completely Randomized Group Design (CRGD). The results showed that the combination of concentration of 750 ppm streptomycin within 48 hours of soaking showed the best results among other treatments with an average putative mutant percentage of 73.33%. Further test results showed that the most optimum combination of concentration and duration of immersion of streptomycin to produce Monstera adansonii variegated was a concentration of 860 ppm with a soaking time of 81.64 hours. Both levels are not included in the levels carried out in the study.
Keyword: monstera, concentration, soaking time, streptomycin, variegate

Judul: In vitro Induced Mutation of Anthurium Plants Using Streptomycin Antibiotic
Abstrak: Anthurium dibudidayakan sebagai bunga potong dan juga tanaman hias daun. Telah banyak hibrida dan kultivar Anthurium yang beredar, akan tetapi Anthurium variegata masih jarang ditemukan dan juga memiliki nilai yang tinggi, oleh karena itu perlu dilakukan induksi mutasi untuk memperoleh mutan variegata. Penelitian ini bertujuan mempelajari lama perendaman dan konsentrasi antibiotik streptomycin, serta mendapatkan lethal concentration 50 (LC50) yang sesuai untuk menginduksi mutasi variegata pada Anthurium clarinervium dan Anthurium gracile. Penelitian dilaksanakan pada bulan November 2023 hingga April 2024 di Laboratorium Bioteknologi Tanaman 3, IPB University. Hasil penelitian menunjukkan persentase mutan putatif variegata tertinggi diperoleh pada perlakuan lama perendaman 24 jam dan konsentrasi streptomycin 1000 ppm pada Anthurium clarinervium. Jumlah total mutan putatif variegata pada Anthurium clarinervium adalah sebanyak lima individu, dan pada Anthurium gracile adalah sebanyak 75 individu. Nilai LC50 pada Anthurium clarinervium dengan lama perendaman 24 jam adalah 4233,03 ppm, dan dengan lama perendaman 48 jam adalah 1541,68 ppm. Nilai LC50 pada Anthurium gracile dengan lama perendaman 24 jam adalah 6101,92 ppm., Anthuriums are cultivated as cut flowers and as ornamental foliage. There are many Anthurium hybrids and cultivars, but Anthurium variegata is still rarely found and also has high values. Variegated mutants can be obtained, among others, through mutation induction. This research aims to study the soaking time and concentration of the antibiotic streptomycin, and to determine the appropriate lethal 50 concentration (LC50) to induce variegated mutations in Anthurium clarinervium and Anthurium gracile. The research was carried out from November 2023 to April 2024 at the Plant Biotechnology Laboratory 3, IPB University. The results of the study showed that the highest percentage of variegated putative mutants was obtained in the treatment of 24 hours of immersion and a streptomycin concentration of 1000 ppm on Anthurium clarinervium. The total number of putative variegated mutants in Anthurium clarinervium was five individuals, and in Anthurium gracile there were 75 individuals. The LC50 value for Anthurium clarinervium with a soaking time of 24 hours was 4233,03 ppm, and with a soaking time of 48 hours it was 1541,68 ppm. The LC50 value for Anthurium gracile with a soaking period of 24 hours was 6101,92 ppm.
Keyword: Araceae, chemical mutation, genetic diversity, lethal concentration 50, variegata

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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