Judul: Effects of Fertilizer Types and Pruning on the Yield of Peanut (Arachis hypogaea L.) Pelanduk Variety
Abstrak: Kacang tanah merupakan tanaman Leguminosae yang sudah banyak dikenal dan dibudidayakan di Indonesia. Namun, produksi kacang tanah di Indonesia masih rendah dan cenderung stagnan. Hal ini disebabkan oleh tidak tersedianya lahan yang cukup luas untuk memproduksi kacang tanah serta teknik budidaya yang masih tergolong tradisional. Tujuan penelitian ini adalah untuk mempelajari pengaruh penggunaan beberapa jenis pupuk dan pemangkasan terhadap daya hasil tanaman kacang tanah varietas Pelanduk. Penelitian ini dilaksanakan di Kebun Percobaan Institut Pertanian Bogor, Desa Cikarawang, Kabupaten Bogor dari bulan Maret sampai Juni 2020. Penelitian ini menggunakan kacang tanah varietas Pelanduk dengan rancangan petak terbagi (split plot) dua faktor perlakuan. Petak utama adalah perlakuan pemberian beberapa jenis pupuk yang terdiri dari 5 taraf yaitu, tanpa pupuk, NPK Mutiara 300 kg ha-1, NPK Mutiara 300 kg ha-1 + kapur Dolomit 1 ton ha-1, pupuk kandang 1 ton ha-1 + pupuk daun 2 ml l-1, dan pupuk kandang 1 ton ha-1 + pupuk daun 2 ml l-1 + kapur Dolomit 1 ton ha-1. Pemangkasan sebagai anak petak terdiri dari 3 taraf yaitu, tanpa pangkas, pemangkasan 1 cabang lateral, dan pangkas batang utama. Perlakuan jenis pupuk memberikan pengaruh yang nyata pada hasil kacang tanah yaitu peubah bobot basah ubinan, bobot kering ubinan, dan produktivitas polong tanaman kacang tanah. Sedangkan pada perlakuan pemangkasan dan interaksi antara keduanya tidak memberikan hasil yang berpengaruh secara nyata. Hasil penelitian menunjukkan bahwa pemberian pupuk NPK Mutiara 300 kg ha-1 + kapur Dolomit 1 ton ha-1 memberikan hasil yang lebih tinggi pada peubah komponen hasil, namun tidak berbeda nyata dari pupuk NPK Mutiara 300 kg ha-1., Peanut is a Leguminoceae plant that is widely known and cultivated in indonesia. However, peanut production in Indonesia is still low and tends to be stagnant. This is caused by the unavailability of large enough land to produce peanuts and cultivation techniques that are still classified as traditional. The purpose of this research was to study the effect of using several types of fertilizers and pruning on the yield of Pelanduk peanut variety. This research was conducted at the Experimental field of the Bogor Agricultural University, Cikarawang Village, Bogor Regency from March to July 2020. This research used peanut varieties Pelanduk with split plot design of two treatment factors. The main plot is the treatment of giving several types of fertilizers consisting of 5 levels, namely, without fertilizer, NPK Mutiara 300 kg ha-1 , NPK Mutiara 300 kg ha-1 + Dolomite lime 1 ton ha-1 , manure 1 ton ha-1 + leaf fertilizer 2 ml l-1 , and manure 1 ton ha-1 + leaf fertilizer 2 ml l-1 + Dolomite lime 1 ton ha-1 . Pruning as a subplot consists of 3 levels, namely, without pruning, pruning 1 lateral branch, and pruning the main stem. Treatment of the type of fertilizer had a significant effect on the yield of peanuts, namely the variables of the wet weight of the tuberose, the dry weight of the tuberose, and the productivity of peanut pods. Meanwhile, the pruning treatment and the interaction between the two did not give any significant effect. The results showed that the application
Keyword: fertilizer types, peanuts, production, productivity, pruning

Judul: The Effect of Type and Pruning Time for Peanuts (Arachis hypogaea) Production of Zebra Varieties
Abstrak: Hasil produksi kacang tanah dapat ditingkatkan dengan cara melakukan pemangkasan pada cabang tanaman. Pemangkasan pada cabang diharapkan dapat menekan laju pertumbuhan vegetatif sehingga laju pertumbuhan generatif meningkat. Penelitian ini bertujuan mengetahui jenis pangkas dan waktu pangkas yang berpengaruh terhadap hasil produksi kacang tanah. Penelitian ini dilaksanakan di Kebun Percobaan Leuwikopo IPB pada bulan November 2020 sampai Maret 2021. Rancangan percobaan yang digunakan dalam penelitian ini adalah rancangan petak terbagi (split-plot) dengan petak utama merupakan jenis pangkas dan anak petak merupakan waktu pangkas. Jenis pangkas yang digunakan adalah tanpa pangkas, pangkas batang utama, dan pangkas cabang lateral. Waktu pangkas adalah pada saat tanaman berumur 6 MST, 8 MST, dan 10 MST. Hasil penelitian menunjukkan jenis pangkas berpengaruh nyata terhadap jumlah cabang lateral pada 8 MST, 10 MST, dan 12 MST. Jenis pangkas juga berpengaruh nyata terhadap bobot 100 biji. Waktu pangkas tidak memberikan pengaruh yang nyata terhadap peubah pengamatan yang diamati. Interaksi antar kedua perlakuan berpengaruh nyata terhadap bobot 100 biji., Peanuts production can be increased by pruning plant branches. Pruning is expected can be suppressed the vegetative growth rate so that the generative growth rate increases. The purpose of this research is to find out which type and time pruning that can affect peanuts production. This research was conducted in Leuwikopo Experimental Station IPB on November 2020 until March 2021. This research is arranged in split-plot randomized block design with the main plot is the type of pruning and the subplot is time of pruning. The types of pruning are without pruning, main branches pruning, and lateral branches pruning. Time of pruning is when the age of the plant are 6 weeks after planting, 8 weeks after planting, and 10 weeks after planting. The result shows that type of pruning affects the number of lateral branches at week 8, week 10, and week 12. Type of pruning also affects weight of 100 seeds. Time of pruning does not have significant effect on the observed variables. Interaction between the two treatments affect the weight of 100 seeds.
Keyword: generative growth rate, peanuts, productivity, type of pruning

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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