Judul: The Effect of N Doses Fertilizer and Varieties on Corn Growth and Production in Saturated Soil Culture in Rice Fields
Abstrak: Jagung (Zea mays L.) merupakan komoditas pangan kedua setelah beras yang berperan sebagai sumber karbohidrat. Peningkatan konsumsi jagung perlu diseimbangi dengan peningkatan produktivitas. Penelitian bertujuan mengetahui pengaruh dosis pupuk N dan varietas terhadap pertumbuhan dan produksi jagung pada budidaya jenuh air di lahan sawah. Penelitian menggunakan rancangan percobaan RKLT dengan dua faktor yaitu varietas dan dosis pupuk N. Faktor varietas terdiri atas dua taraf yaitu jagung Sukmaraga dan Pioneer 27. Faktor dosis pupuk N terdiri atas 0 kg N ha-1, 90 kg N ha-1, 135 kg N ha-1, dan 180 kg N ha-1. Hasil penelitian menunjukkan bahwa faktor varietas menunjukkan hasil yang berbeda di awal pertumbuhan yaitu pada karakter tinggi tanaman, diameter batang, dan jumlah daun, serta bobot basah akar. Selain itu terdapat perbedaan pada komponen hasil yaitu pada karakter diameter tongkol, jumlah baris biji per tongkol, dan bobot 100 biji. Dosis N 180 kg N ha-1 memberikan hasil terbaik untuk semua karakter pertumbuhan dan produksi namun tidak berbeda nyata dengan dosis N 135 kg N ha-1. Tidak terjadi interaksi antara faktor varietas dan dosis N., Corn (Zea mays L.) is the second food commodity after rice which acts as a carbohydrate source. Increased consumption of corn needs to be balanced with productivity. This study aims to determine the effect of N fertilizer dosage and varieties on the growth and production of maize in saturated soil culture in paddy fields. This study used an Randomized Complete Block design (RCBD) with two factors, namely the variety and dose of N fertilizer. Variety factors consisted of two levels, namely Sukmaraga and Pioneer 27. The dosage factor for N fertilizer consisted of 0 kg N ha-1 , 90 kg N ha-1, 135 kg N ha-1, and 180 kg N ha-1. The results of this study indicated that the variety factor showed different results at the character of plant height, stem diameter, number of leaves, and root wet weight,the ear diameter, number of seed rows per ear, and the weight of 100 seeds. The N dose of 180 kg N ha-1 gave the best results for all growth and production characters but was not significantly different from the N dose of 135 kg N ha-1. There was no interaction between the variety factor and the N dose.
Keyword: Nitrogen dose, Pioneer 27, Saturated soil culture, Sukmaraga

Judul: The Effect of Phospate Fertilization on Growth and Production Two Variety of Corn with Saturated Soil Culture in Rice Fields
Abstrak: Salah satu upaya untuk meningkatkan produksi jagung yaitu dengan memanfaatkan lahan basah untuk budidaya jagung, karena selama ini mayoritas jagung dibudidayakan pada lahan kering. Teknik budidaya jenuh air merupakan teknik dalam budidaya pada lahan basah untuk meningkatkan produksi dan produktivitas kedelai. Budidaya jenuh air menggunakan olah tanah minimum dengan dosis pemupukan yang tepat dapat menurunkan biaya dalam usaha budidaya. Penelitian ini bertujuan untuk mengetahui pemilihan varietas dan dosis pemupukan P yang tepat terhadap produksi jagung yang dibudidayakan dengan teknik budidaya jenuh air di lahan sawah. Penelitian dilakukan pada bulan Agustus hingga Desember 2020 di Kebun Percobaan Sawah Baru Institut Pertanian Bogor. Penelitian ini menggunakan rancangan kelompok lengkap teracak (RKLT) dua faktor yaitu varietas (Sukmaraga dan Pioneer-27) dan dosis pupuk P (0 kg P2O5 ha-1, 18 kg P2O5 ha-1, 36 kg P2O5 ha-1, 108 kg P2O5 ha-1) yang terdiri dari 8 satuan percobaan yang diulang sebanyak 3 kali. Berdasarkan penelitian yang telah dilakukan, varietas Pioneer-27 merupakan varietas yang direkomendasikan karena varietas Pioneer-27 mampu menghasilkan produktivitas yang lebih tinggi. Dosis pemupukan 108 kg P2O5 ha-1 merupakan dosis yang direkomendasikan dalam budidaya jagung dengan teknik budidaya jenuh air di lahan sawah, karena memberi pengaruh yang nyata terhadap produkstivitas jagung pipil kering., One of the attemps to increase corn producion is using wet land for corn cultivation, because so far the majority of corn cultivated in the dry land. The saturated soil culture is a technique for cultivation in the wet land in order to increase production and productivity of corn. Saturated soil culture which is using minimum tillage with correctly dose of fertilizer can decrease cost of cultivation. This research purpose is to find out the good variety and the optimum dose of phospate fertilizer for corn production which is cultivated with under saturated soil culture in the paddy fields. The research has been done in August until December 2020 at Sawah Baru Experimental Station, IPB University. This research consisted two factors and using randomized complete block design (RCBD). The factors were variety (Sukmaraga and Pioneer-27) and phospate fertilizer dose (0 kg P2O5 ha-1, 18 kg P2O5 ha-1, 36 kg P2O5 ha-1, 108 kg P2O5 ha-1). The reseacrch consisted of 8 experimental units which repeated 3 times. Based on research which has been done, Pioneer-27 variety is a recommended variety because performed the higher production of corn. The dose of feretilization 108 kg P2O5 ha-1 is a recommended dose in corn cultivation with saturated soil culture in paddy fields, because show obvious effect to corn productivity.
Keyword: aturated soil culture, rice fields, phospate fertilization, productivity, corn

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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