Judul: Pengaruh Plant Growth Promoting Rhizobacteria (PGPR) dan Pupuk Mikro terhadap Penyakit Karat Puru dan Pertumbuhan Tanaman Sengon (Paraserianthes falcataria) di Lapangan
Abstrak: Albizia is one of the forest tree which was chosen by many farmers to be cultvated as wood source. Gall rust caused by Uromycladium tepperianum is a most devastating disease in albizia plantation in Java. Until now there is no effective control technique to suppress rust gall disease. The treatments was PGPR by the dosage of 1:50 and 1:100 (mixed with synthetic fertilizer), the micro fertilizer, the combination of PGPR and micro fertilizer, and fungcide a.i. mancozeb. The experiment was done by randomized block design by four blocks. The research were caried out in field scale for 11 week. The heigh of the plants, the diameter of trunk, diseases incidence and disease severity were measure. Beside that the AUDPC (Area Under Disease Progress Curve) and the development of the disease were calculated. Based on this research, PGPR 50 and PGPR 100 are proven to be effective in suppressing gall rust and increasing plant growth. But the micro fertilizer (guano) and PGPR + micro fertilizer were not effective in in suppressing gall rust and increasing plant growth
Keyword: 

Judul: Efektivitas penggunaan pupuk organik cair terhadap pertumbuhan tegakan sengon dan tingkat keparahan penyakit karat tumor
Abstrak: Penanaman sengon (Paraserianthes falcataria (L.) Nielsen) dengan pola monokultur sangat rentan terhadap serangan penyakit. Salah satunya adalah penyakit karat tumor, yang disebabkan oleh fungi Uromycladium tepperianum. Penyakit ini dapat mematikan tanaman yang terserang. Salah satu cara untuk meningkatkan ketahanan tanaman sengon terhadap serangan patogen tersebut yaitu dengan pemberian pupuk organik cair (POC). Tujuan dari penelitian ini untuk menguji efektifitas POC terhadap pertumbuhan (tinggi dan diameter) tegakan sengon, serta mengamati pengaruh pemupukan terhadap tingkat keparahan penyakit karat tumor pada tegakan sengon di hutan rakyat Desa Sukaresmi, Kabupaten Cianjur. Rancangan percobaan yang digunakan adalah Rancangan Acak Kelompok, dengan kelompok dibedakan berdasarkan kondisi lahan, yang terdiri dari 2 taraf (lahan datar dan lahan berlereng) dan perlakuan berdasarkan dosis pupuk organik cair, yang terdiri dari 5 taraf yaitu 0, 4, 8, 10, 12 ml/l. Hasil penelitian menunjukkan pemberian dosis pupuk organik cair tidak berpengaruh nyata terhadap pertumbuhan tinggi dan diameter tanaman sengon di dua kondisi lahan. Pengaruh yang nyata diperoleh pada intesitas serangan patogen penyakit karat tumor (IS) terendah (20%) pada lahan datar, dengan dosis pupuknya 0 ml/l (kontrol). Pemupukan dengan beberapa dosis pupuk organik cair, kurang efektif diberikan pada sengon berumur dua tahun. Hal ini dikarenakan pemupukan yang dilakukan tidak mampu menghambat serangan patogen penyebab karat tumor.
Keyword: Gall Rust Disease, Liquid Orgnanic Fertilizer, Paraserianthes falcataria

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.
Keyword: