Judul: Evaluation of Stylo Plants (Stylosanthes guianensis) that are Salinity Resistant by Treatment with the Chemical Mutagen Colchicine
Abstrak: Stylosanthes guianensis merupakan leguminosa dengan nutrisi tinggi dan palatabilitas tinggi. Perbaikan mutu genetik tanaman pakan sangat berpotensi untuk dilakukan sebagai upaya peningkatan produksi hijauan pakan terutama di tanah salin. Tujuan dari penelitian ini yaitu mengeveluasi tanaman stylo hasil induksi mutagen kimia kolkisin yang tahan salinitas sedang dan tinggi. Tanaman dalam penelitian ini berumur 10 minggu hasil induksi kolkisin 8, 12, dan 16 hari dengan level kolkisin 0 ppm (kontrol), 5, 10, 15, 20, 25, dan 30 ppm yang di tanam pada tanah salin sedang dan tinggi selama 10 minggu. Peubah morfologi tanaman meliputi daya tumbuh, jumlah daun trifoliate, tinggi vertikal, diameter batang, jumlah cabang, dan panjang daun trifoliate. Analisis data yang digunakan ialah uji deskriptif menggunakan aplikasi Microsoft Excel 365. Hasil penelitian perlakuan dengan menggunakan tanah salin sedang (5,45 dS/m) mempunyai daya tumbuh 0%-60%, sedangkan pada tanah salin tinggi (8,65 dS/m) 0%-40%. Peubah yang diukur mempunyai nilai bervariasi. Kesimpulannya tanaman di tanah salin sedang terbaik adalah umur induksi 16 hari dengan level kolkisin 25 ppm. Tanaman di tanah salin tinggi terbaik adalah umur induksi 12 hari dengan level kolkisin 20 ppm., Stylosanthes guianensis is a legume with high nutrition and high palatability. Improvement of genetic quality of forage plants has great potential to be done as an effort to increase forage production, especially in saline soil. The purpose of this study was to evaluate stylo plants resulting from colchicine chemical mutagen induction that are resistant to moderate and high salinity. The plants in this study were 10 weeks old resulting from colchicine induction for 8, 12, and 16 days with colchicine levels of 0 ppm (control), 5, 10, 15, 20, 25, and 30 ppm planted in moderate and high saline soil for 10 weeks. Plant morphological variables include growth rate, number of trifoliate leaves, vertical height, stem diameter, number of branches, and length of trifoliate leaves. The data analysis used was a descriptive test using the Microsoft Excel 365 application. The results of the treatment study using medium saline soil (5.45 dS/m) had a growth rate of 0%-60%, while in high saline soil (8.65 dS/m) 0%-40%. The variables measured had varying values. In conclusion, the best plants in medium saline soil were 16 days of induction age with a colchicine level of 25 ppm. The best plants in high saline soil were 12 days of induction age with a colchicine level of 20 ppm.
Keyword: salinitas, kolkisin, Stylosanthes guianensis, colchicine, salinity

Judul: Optimization of Cholchichine Levels and Soaking Time to Increase The Production of Stylo (Stylosanthes guianensis)
Abstrak: Kolkisin merupakan mutagen kimia yang menyebabkan penggandaan pada kromosom tumbuhan sehingga dihasilkan tanaman poliploid. Penelitian ini bertujuan untuk mengetahui level dan lama perendaman kolkisin yang optimum untuk peningkatan produksi tanaman stylo. Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) faktorial dengan 2 faktor dan 6 ulangan. Faktor A merupakan level kolkisin yang terdiri dari 0 ppm, 25 ppm, 50 ppm, 75 ppm dan 100 ppm. Faktor B merupakan lama perendaman yang terdiri dari 12 jam, 24 jam dan 36 jam. Data yang diperoleh dianalisis dengan menggunakan General Linear Model (GLM) dan uji lanjut Duncan dengan software SPSS versi 25. Peubah yang diamati pada aspek morfologi meliputi tinggi vertikal, diameter batang, panjang daun, lebar daun, jumlah anak daun, jumlah daun trifoliate dan panjang daun trifoliate beserta tangkainya, sedangkan pada aspek biomassa tanaman meliputi bobot kering tajuk dan bobot kering akar. Hasil penelitian menunjukkan bahwa kolkisin level 25 ppm dan 12 jam berpengaruh nyata (p<0,05) terhadap peningkatan tinggi vertikal, diameter batang, dan lebar daun. Kolkisin level 25 ppm berpengaruh nyata (p<0,05) terhadap peningkatan bobot kering akar., Colchicine is a chemical mutagen that causes doubling of plant chromosomes into polyploid plants. This study aimed to determine the optimal level and soaking time of colchicine to increase the production of stylo plants. This study used a factorial Completely Randomized Design (CRD) with 2 factors and 6 replications. Factor A is colchicine level consisting of 0 ppm, 25 ppm, 50 ppm, 75 ppm and 100 ppm. Factor B is soaking time consisting of 12 hours, 24 hours and 36 hours. The data obtained were analyzed using the General Linear Model (GLM) and further testing by Duncan's Multiple Range Test (DMRT) with SPSS software version 25. The variables observed in the morphology aspect included vertical height, stem diameter, leaf length, leaf width, number of leaflets, number of trifoliate leaves and length of trifoliate leaves and their stalk, while in plant biomass aspects included crown dry weight and root dry weight. The results showed that the administration of colchicine at a level of 25 ppm and 12 hours had a significant effect (p<0,05) on increasing vertical height, stem diameter, and leaf width. Colchicine level 25 ppm had a significant effect (p<0,05) on the increase root dry weight parameters.
Keyword: Biomass, Colchichine level, Morphology, Soaking time, Stylo

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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