Judul: Perbandingan Pengelolaan Tanaman Berbasis PHT dan Konvensional Pada Tanaman Jagung (Zea mays ) di Nganjuk , Jawa Timur.
Abstrak: One of factors that results in suboptimum productivity of corn is lack of good management and cultivation, and the presence of plant pests and diseases. Several attempts to improve the productivity of corn has been developed continuously, including the use of natural agents such as Plant Growth Promoting Rhizobacteria (PGPR) and fungal biocontrol agents as control component in IPM. The objective of this study was to compare IPM based corn crop management involving PGPR and bicontrol agents with conventional method on plant growth, yield, and pest/diseases occurence. Field observations of the crop pests and diseases, and their intensity and severity were conducted as well as measurements of plant height, girth, number of leaves, and number of cobs. Interview with the farmer was also done. The use of PGPR containing mixture of Pseudomonas fluorescens and Bacillus polymixa combined with application of Trichoderma sp., Verticillium sp., and organic fertilizer to meet IPM concepts resulted in maintaining optimum plant height, number of leaves, and number of cobs. The plant also showed to acquire resistance against pests and diseases. In general, the IPM based plant management gives better performance of growth and yield and lower occurence of corn pest and diseases than that of conventional method. The cost for growing corn based on IPM was higher than that conventional method, however, gave more yield benefit. IPM approach is concluded to be more profitable than conventional method.
Keyword: 

Judul: Response of Growth and  Production of Corn  to The Combination of Various Types of Biological Fertilizer and NPK
Abstrak: Jagung (Zea mays L.) merupakan tanaman serealia penting ketiga di dunia. Namun, dalam proses budidayanya masih mengandalkan pupuk kimia sebagai sumber hara bagi tanaman. Penggunaan pupuk kimia yang terus menerus ini dapat berpotensi menurunkan produktivitas tanah. Pengaplikasian pupuk hayati dapat menjadi salah satu solusi untuk meningkatkan kesuburan tanah. Penelitian ini bertujuan mempelajari efektivitas kombinasi pemberian berbagai jenis pupuk hayati dan NPK terhadap pertumbuhan dan produksi tanaman jagung. Penelitian dilaksanakan di KP Sawah Baru pada Desember 2023-Februari 2024. Rancangan percobaan yang digunakan adalah rancangan split-plot dengan faktor NPK sebagai petak utama yang terdiri dari dua taraf dan pupuk hayati sebagai anak petak yang terdiri dari 5 taraf. Hasil penelitian menunjukkan pemberian jenis pupuk hayati berpengaruh nyata terhadap pertumbuhan dan komponen hasil jagung yang ditandai dengan peningkatan tinggi, diameter batang, kehijauan daun, bobot brangkasan, panjang tongkol, diameter tongkol, dan kemanisan jagung., Corn (Zea mays L.) is the third important cereal crop in the world. However, in the cultivation process it still relies on chemical fertilizers as a source of nutrients for plants. The continuous use of chemical fertilizers can potentially reduce soil productivity. The application of biofertilizers can be one of solution to increase soil fertility. This research aims to study the effectiveness of the combination of applying various types of biofertilizers and NPK on the growth and production of corn plants. The research was conducted in Sawah Baru in Experimental Station December 2023-February 2024. The experimental design used was a split-plot design with NPK factors as the main plot consisting of two levels and biofertilizer factors as subplots consisting of 5 levels. The results showed that the application of this type of biofertilizer had a significant effect on the growth and yield components of corn, which were characterized by an increase in height, stem diameter, leaf greenness, strand weight, cob length, cob diameter, and corn sweetness.
Keyword: corn, effectiveness, biofertilizer, NPK, combination

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: