Judul: Vegetative growth responses to the applications of compost from biomass of seasonal plants of the same and different species and in vitro test of self-DNA effects
Abstrak: Pengembalian biomassa tanaman ke dalam tanah yang dimaksudkan untuk mempertahankan status kesuburan tanah saat ini menghadapi tantangan terkait dampak negatif Self-DNA terkait dengan penerapan kompos yang dibuat dari biomassa dari spesies tanaman yang sama pada tahap kematangan kompos tertentu. Penelitian ini bertujuan untuk mengevaluasi pengaruh aplikasi kompos yang dibuat dari biomassa spesies tanaman pangan yang sama dan berbeda dengan periode pengomposan yang berbeda terhadap pertumbuhan vegetatif padi, jagung, dan kacang panjang dan ekstrak DNA dari kompos yang diterapkan pada perkecambahan biji oadi, jagung dan kacang panjang. Percobaan menggunakan RAL dengan 10 perlakuan [kontrol, k (bahan kompos): biomassa padi (P), jagung (J), dan kacang panjang (K), dan waktu pengomposan: 0, 30, dan 90 hari]. DNA diisolasi dengan metode CTAB yang dimodifikasi. Hasil penelitian menunjukkan bahwa aplikasi kompos matang mendukung pertumbuhan vegetatif tanaman uji, sedangkan perlakuan kP30 dan kJ30, masing-masing untuk aplikasi biomassa padi dan jagung kompos 30 hari, menunjukkan efek penghambatan terhadap pertumbuhan vegetatif spesies yang sama (kompos padi atau jagung yang diterapkan pada tanaman padi atau jagung). Namun, efek penghambatan Self-DNA secara in vitro tidak konsisten sehingga dianggap tidak terjadi dalam percobaan ini, Returning-back unharvested crop biomass into soil which is intended to maintain soil fertility status is now facing a challenge concerning self-DNA negative impacts related to the application of compost prepared from biomass of the same crop species at certain compost maturity stage. This study aimed at to evaluate the application effects of composts prepared from biomass of the same and different food crop species with different composting periods on the vegetative growth of rice, maize, and string beans and of DNA extracts from the applied composts on seed germination of the studied crops. The experiment applied CRD with 10 treatments [control, k (compost materials): rice (P), maize (J), and string beans (K) biomass, and composting periods: 0, 30, and 90 d]. DNA was isolated by the modified CTAB method. The results showed that application of mature compost supported the vegetative growth of the test crops, while kP30 and kJ30 treatments, stands respectively for the application of 30 days-composted rice and maize biomass, showed inhibitory effect to the vegetative growth of the same species (rice or maize compost applied to rice or maize cropping). However, in vitro self-DNA inhibition effect was inconsistent and therefore considered not occurred in this experiment.
Keyword: agronomic performance, growth inhibitory effect, in vitro seed germination, seasonal crops

Judul: Application of Compost and Bionanomaterials in Peatland for Shorea balangeran (Korth.) Burck Agroforestry with Rice
Abstrak: Lahan gambut dengan karakteristik kesuburan rendah dan rentan terdegradasi memerlukan upaya dalam peningkatan produktivitas dan konservasi. Hal yang dapat dilakukan adalah aplikasi kompos serasah Shorea balangeran dan bionanomaterials dalam sistem agroforestri. Penelitian ini bertujuan menganalisis pengaruh bionanomaterials dan perbedaan varietas terhadap perkecambahan padi secara in vitro, pengaruh bahan ameliorant dan varietas terhadap pertumbuhan padi secara in vivo, dan pengaruh bahan ameliorant terhadap sifat kimia tanah. Uji kecambah padi secara in vitro dilakukan pada cawan Petri yang dimasukkan ke germinator selama 21 hari. Uji in vivo dilakukan di rumah kaca dengan campuran media dan penggenangan. Bionanomaterials berpengaruh pada respon kecambah normal, laju perkecambahan, dan tinggi kecambah pada uji in vitro. Bionanomaterials tandan kosong kelapa sawit aktivasi taraf 5% (TA5) menghasilkan persen hidup padi tertinggi diikuti dengan kompos S. balangeran pada uji in vivo. Bionanomaterials mampu meningkatkan kesuburan tanah, sedangkan kompos S. balangeran menyediakan kondisi optimum walaupun belum matang. Oleh karena itu, bionanomaterials dan kompos S. balangeran dapat diaplikasikan pada lahan gambut dengan sistem agroforestri., Peatlands with low fertility characteristics and degradation risk require efforts to improve productivity and conservation. What can be done is the application of Shorea balangeran litter compost and bionanomaterials in agroforestry systems. This study aims to analyze the influence of bionanomaterials and varieties differences on in vitro rice germination, the influence of ameliorant and variety materials on in vivo rice growth, and the influence of ameliorant material on the chemical properties of soil. In vitro rice germination test is conducted on Petri dish which is put in germinator for 21 days. In vivo tests are conducted in a greenhouse with a mixture of media and weeding. Bionanomaterials had an effect on normal sprout response, germination rate, and sprouts height in in vitro tests. Bionanomaterials of empty palm oil activation levels of 5% (TA5) produced the highest percent of rice life followed by S. balangeran compost in in vivo tests. Bionanomaterials are able to improve soil fertility, while S. balangeran compost provides optimum conditions although immature. Therefore, bionanomaterials and compost S. balangeran can be applied to peatlands with agroforestry systems.
Keyword: germination, growth response, in vitro, in vivo

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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