Judul: Growth Characteristics of Mutant Lamtoro Var.  Tarramba Acid Tolerant pH 3.4 on Field Scale at JASTRU Jonggol
Abstrak: Peningkatan adaptabilitas mutan lamtoro var. tarramba pada kondisi masam pH 3,4 diharapkan tidak menurunkan potensi adaptasinya pada lingkungan normal skala lapang. Evaluasi karakteristik pertumbuhan mutan tanaman lamtoro var. tarramba pada skala lapang dilaksanakan di Unit Pendidikan dan Penelitian Peternakan Jonggol (UP3J). Tujuan penelitian ini adalah mengevaluasi karakteristik pertumbuhan mutan lamtoro var. tarramba toleran masam pH 3,4 pada skala lapang di UP3J. Penelitian ini menggunakan Rancangan Acak Kelompok (RAK) dengan 11 mutan lamtoro (T1-T11) yang terdiri dari masing masing lima ulangan dan lamtoro kontrol positif (T0) yang terdiri dari empat ulangan. Data morfologi (tinggi tanaman, diameter batang, jumlah ranting, dan jumlah tangkai induk daun majemuk) dianalisis dengan sidik ragam (ANOVA). Hasil yang berbeda nyata dilakukan analisis lanjut DMRT. Data warna tanah rizosfer, pH rizosfer, warna daun, dan serangan hama kutu loncat dianalisis secara deskriptif. Variabel penelitian terdiri dari warna tanah rizosfer, pH tanah rizosfer, tinggi tanaman, diameter batang, jumlah ranting, jumlah tangkai induk daun majemuk, warna daun, dan serangan hama kutu loncat. Hasil penelitian menunjukkan mutan T10, T11, dan T12 menghasilkan nilai pH akhir rizosfer yang cenderung lebih masam dibandingkan tanaman lainnya. Mutan tanaman lamtoro var. tarramba toleran masam pH 3,4 pada media tanah kategori agak masam hingga netral memberikan hasil sama baik dengan kontrol positif lamtoro var. tarramba pada parameter karakteristik morfologi, warna daun, serta serangan hama kutu loncat, Improved adaptability of lamtoro var. tarramba in acid condition pH 3.4 in controlled enviroments is expected not to reduce its potential adaptation in the normal environment of the field scale. Evaluation of the growth characteristics of lamtoro var. tarramba mutant on the filed scale was carried out at the Jonggol Animal Science Teaching and Research Unit (JASTRU). The aim of this study is to evaluate the growth characteristics of lamtoro var. tarramba mutant acid tolerant pH 3.4 on a field scale at JASTRU. This study was designed by using Randomized Block Design (RBC) with 11 lamtoro mutants (T1-T11) consisting of five replications and positive control lamtoro (T0) consisting of four replications. Morphological data (plant height, stem diameter, number of twigs, and number of compound leaf stalks) were analyzed using analysis of variance (ANOVA). The significant different result futher analyzed with DMRT. Data of rhizosphere soil color, rhizosphere pH, leaf color, and fleas attack were analyzed descriptively. Observed variables consisted of rhizosphere soil color, rhizosphere pH, plant height, stem diameter, number of twigs, number of stalks of compound leaf, leaf color, and fleas attack. The results showed mutants with code T10, T11, and T12 produced the final rhizosphere pH more acidic than others. Mutant of lamtoro var. tarramba acid tolerant pH 3.4 on moderately acidic to neutral soil media is as good as positive control of lamtoro var. tarramba on morphological characteristics, leaf color, and attack of fleas variables.
Keyword: genetics, growth characterstics, lamtoro var. tarramba mutant, nutrient uptake

Judul: Growth Characteristics of the Lamtoro Mutant Candidate  (Leucaena leucocephala cv. Tarramba) M2 Generation Tolerant of Acid Stress
Abstrak: Varietas tanaman Lamtoro yang toleran terhadap tanah masam perlu dikembangkan agar tanah masam menjadi produktif dan dapat dimanfaatkan untuk meningkatkan produksi tanaman. Penelitian ini bertujuan untuk mengukur sifat morfologi dan mutu benih serta mengevaluasi pertumbuhan tanaman mutan lamtoro beradaptasi pada tanah masam hasil iradiasi sinar gamma melalui kultur jaringan sehingga diperoleh mutan dengan mutu benih unggul. Sebanyak 4 kandidat mutan lamtoro digunakan dalam penelitian ini, dan mereka telah mengembangkan adaptasi terhadap tanah masam. Penelitian dilakukan dengan menggunakan rancangan acak lengkap; 4 kandidat mutan dan satu tanaman kontrol digunakan sebagai perlakuan. Analisis data yang digunakan dalam penelitian ini adalah koefisien variasi, Analysis of Variance (ANOVA) dan dilanjutkan dengan Uji Jarak Berganda Duncan jika terdapat pengaruh yang signifikan. Karakteristik tanaman kandidat mutan lamtoro generasi M1 bervariasi pada karakter diameter batang, sedangkan tidak bervariasi pada karakter tinggi kanopi, jumlah cabang, dan jumlah ranting. Dominasi sifat polong dan biji terbaik pada calon mutan lamtoro (M2) didominasi oleh calon mutan GLM.1. Seluruh kandidat mutan lamtoro memiliki warna biji yang normal. Berat 100 benih tertinggi diekspresikan oleh kandidat mutan lamtoro GLM.9. Pengelompokan benih kecil, sedang, dan besar secara berturut diekspresikan oleh kandidat mutan GLM.8, GLM.10, dan GLM 9. Tanaman lamtoro GLM.0 dan kandidat mutan lamtoro GLM.8 menunjukkan persentase viabilitas tertinggi. Kandidat mutan lamtoro GLM.8 menunjukkan persentase viabilitas pada media asam tertinggi. Ukuran benih dan viabilitas benih memiliki nilai korelasi yang negatif. Kandidat mutan lamtoro GLM.9 menunjukkan angka kematian tertinggi, sedangkan tingkat kerugian tertinggi ditunjukkan oleh GLM.10. Kandidat mutan lamtoro GLM.9 menunjukkan waktu munculnya tunas tercepat. Seluruh kandidat mutan menunjukkan variasi yang tinggi pada pertambahan tinggi vertikal. Kandidat mutan GLM.1 dan GLM.9 menunjukkan ekspresi jumlah cabang terbaik. Kandidat mutan GLM.1 menunjukkan ekspresi jumlah daun terbaik. Seluruh kandidat mutan lamtoro memiliki warna daun yang normal., Lamtoro plant varieties that are tolerant of acidic soil need to be developed so that acidic soil becomes productive and can be used to increase crop production. This research aims to measure morphological characteristics and seed quality and evaluate the growth of lamtoro mutant plants adapted to acid soil resulting from gamma-irradiation through tissue culture to obtain mutants with superior seed quality. A total of 4 mutant candidates of lamtoro were used in this study, and they had developed adaptation to acidic soils. The research was conducted using a completely randomized design; 4 mutant candidates and one control plant were used as treatments. The data analysis used in this research is the coefficient of variation, analysis of variance (ANOVA) and continued with the duncan multiple range test (DMRT) if there is a significant influence. The characteristics of the M1 generation lamtoro mutant candidate plants varied in stem diameter, while they did not vary in canopy height, number of branches, and number of twigs. The best pod and seed traits in the lamtoro (M2) mutant candidate are dominated by the GLM.1 mutant candidate. All lamtoro mutant candidates have standard seed color. The lamtoro GLM.9 mutant candidate expressed the highest weight of 100 seeds. Groupings of small, medium, and large seeds were expressed respectively by candidate mutants GLM.8, GLM.10, and GLM 9. Lamtoro GLM.0 plants and candidate
Keyword: kandidat mutan, lamtoro, tanah asam

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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