Judul: The Effect of Callus Induction Media and Gamma Ray Irradiation Doses on Growth and Morphology of Celery (Apium graveolens L.).
Abstrak: Induksi keragaman genetik pada tanaman seledri dapat dilakukan dengan kombinasi kultur in vitro dan iradiasi sinar gamma. Perlakuan iradiasi sinar gamma pada kalus dapat membentuk variasi keragaman yang lebih tinggi. Penelitian ini bertujuan untuk mempelajari pengaruh media induksi kalus dan dosis iradiasi sinar gamma yang dapat meningkatkan keragaman kultur kalus seledri. Penelitian dilaksanakan di Laboratorium Kultur Jaringan 3 AGH dan PAIR BATAN pada bulan Januari-Oktober 2021. Penelitian ini menggunakan rancangan acak lengkap dengan dua faktor. Faktor pertama yaitu media induksi kalus: MS + 1,2 ppm 2,4-D dan MS + 0,3 ppm 2,4-D + 0,5 ppm kinetin. Faktor kedua yaitu dosis iradiasi: 0; 2,5; 5,0; 7,5; 10,0; 15; dan 20 Gy. Hasil penelitian menunjukkan bahwa perlakuan media berpengaruh nyata terhadap persentase kalus berakar. Perlakuan dosis iradiasi berpengaruh nyata terhadap laju pertambahan luas kalus, persentase kalus remah dan jumlah daun seledri. Interaksi kedua perlakuan berpengaruh nyata terhadap laju pertambahan luas kalus, persentase kalus berakar, dan jumlah daun seledri. RD50 dari persentase kelambatan pertumbuhan kalus adalah 8,92 Gy. Interaksi media 0,3 ppm 2,4-D + 0,5 ppm Kinetin dan dosis iradiasi 10 Gy meningkatkan keragaman bentuk daun seledri dengan 6 bentuk daun yang berbeda dan menghasilkan planlet yang diaklimatisasi sebanyak 14 planlet., Genetic variance induction on celery can be done by combining in vitro culture and gamma irradiation. Gamma ray irradiation treatment on callus can form a higher diversity variation. This study aims to study the effect of callus induction media and gamma irradiation dose that can increase the diversity of celery callus culture. The research was conducted at the Plant Tissue Culture Laboratory 3 AGH IPB and PAIR BATAN, Jakarta on January-October 2021. This research used the completely randomized design with two factors. The first factor was callus induction medium: MS + 1.2 ppm 2.4-D and MS + 0.3 ppm 2.4-D + 0.5 ppm kinetin. The second factor was irradiation dose: 0, 2.5, 5, 7.5, 10, 15, and 20 Gy. The results showed that media treatment significantly affected the percentage of rooted callus. Gamma ray irradiation dose treatment significantly affected the rate of increase in callus area, the percentage of friable callus and also the number of celery leaves. The interaction of the two treatments significantly affected the rate of increase in callus area, the percentage of rooted callus, and the number of celery leaves. The results of the calculation of RD50 from the percentage of callus growth delay was 8.92 Gy. The interaction of 0.3 ppm 2.4-D + 0.5 ppm Kinetin and 10 Gy irradiation dose was increasing the diversity of celery leaf shapes with 6 different leaf shapes and resulting 14 celery acclimatized plantlets.
Keyword: in vitro, mutagen, mutation, regeneration, somatic embryo

Judul: Mutasi Induksi dengan Iradiasi Sinar Gamma secara Berulang pada Tunas In Vitro Celosia cristata L.
Abstrak: Celosia cristata L. atau lebih dikenal dengan nama bunga jengger ayam adalah tanaman hias dari famili Amaranthaceae. Peningkatan nilai guna dan ekonomi tanaman jengger ayam dapat dilakukan dengan menciptakan keragaman salah satunya melalui mutasi induksi. Penelitian ini bertujuan untuk mengetahui pengaruh iradiasi sinar gamma secara berulang terhadap keragaan tanaman jengger ayam pada generasi MV1 (mutan vegetatif pertama) dan MV2 (mutan vegetatif kedua). Penelitian ini dilaksanakan pada November 2016 hingga April 2017 di Laboratorium Kultur Jaringan 1, Departemen Agronomi dan Hortikultura, Fakultas Pertanian IPB dan iradiasi sinar gamma dilakukan di Pusat Aplikasi Isotop dan Radiasi Badan Tenaga Nuklir Nasional (PAIR BATAN), Pasar Jumat, Jakarta. Hasil penelitian menunjukkan bahwa teknik iradiasi sinar gamma secara berulang berpengaruh terhadap keragaan planlet Celosia cristata L. pada karakter kuantitatif serta kualitatif. Perlakuan dosis terbagi (fractionated irradiation) lebih banyak berpeluang menghasilkan tanaman mutan dibandingkan dengan perlakuan setengah dosis (split dose), terutama pada taraf dosis (35+15) Gy.
Keyword: iradiasi dosis terbagi, iradiasi setengah dosis, mutan, tanaman hias

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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