Judul: Pengaruh Nitrogen dan Rhizobium sp. terhadap Pertumbuhan dan Produksi Kedelai Hitam (Glycine soja) pada Budidaya Jenuh Air di Lahan Pasang Surut
Abstrak: This research aims to determine the optimum concentration of nitrogen fertilizer and influence of Rhizobium sp. as inoculant on the growth and production of black soybeans. The experiment was conducted in the tidal swamps of Banyu Urip village, sub District of Tanjung Lago, Banyuasin District, Palembang, South Sumatera Province from May to September 2013. This research used split plot design with three replications. The concentration of nitrogen as the main plot consisted of 0, 5, 10, and 15 g Urea l-1 water and the Rhizobium sp. as a subplot consist of plus Rhizobium sp. and without Rhizobium sp. Saturated soil culture (SSC) technique was used to support the cultivation of soybeans in tidal swamps. The results showed that the effect of the nitrogen concentration of 15 g Urea l-1 water tends to produce the highest productivity up to 3.775 ton ha-1 and more profitable economically. This is supported by leaf N content to be high at 15 g Urea l-1 water up to 4.89%. Addition of Rhizobium sp. is effective enough increase growth and production although not significantly different. The results also indicate that there is interaction of the two treatments on number of leaves at 4 WAP, then there is no interaction was found on the other variables.
Keyword: tidal swamps, saturated soil culture, Rhizobium sp, nitrogen, black soybean

Judul: Pengaruh Pemupukan Fosfor terhadap Pertumbuhan dan Produksi Beberapa Varietas Kedelai Hitam (Glycine Soja) pad a Budidaya Jenuh Air di Lahan Pasang Surut
Abstrak: Saturated soil culture is a cultivation that gives continuous irrigation and maintains water depth constantly and makes soil layer in saturated condition. Technology of saturated soil culture has been shown to increase soybean production on tidal swamps. The objective of this experiment to study the effect of phosphorus fertilization on the growth and production variety of soybean under saturated soil culture on tidal swamps. The experiment was conducted at Banyu Urip, Tanjung Lago, Banyuasin, South Sumatera, Indonesia from May to September 2013. The experiment used a split plot design with three replications. The main plot of the experiment is black soybean variety consisted of : Ceneng, Cikuray, Lokal Malang and Tanggamus as control . Sub plot is the dosage of phosphorus fertilization consisted of : 0, 36, 72 and 108 kg P2O5 ha-1. The results showed that the variety and phosphorus fertilization affected soybean productivity. The highest productivity was obtained on Cikuray variety with phosphorus fertilization 108 kg P2O5 ha-1 as much as 4.03 ton ha-1.
Keyword: Tidal Swamp, Saturated Soil Culture, Phosphorus Fertilization, Black Soybean Variety

Judul: Penggunaan Teorema Homeomorphy 2-Manifold dan Teorema Euler Poincare pada Torus 𝑇�� dan Simplicial Complex 𝐾��
Abstrak: Two dimensional topological spaces are said to be homeomorphic if they have the same topological invariant, where one of topological invariant used is an Euler characteristic. Homeomorphy 2-Manifold’s Theorem and Euler Poincare’s Theorem are used to distinguish two topological spaces. Homeomorphy 2-Manifold’s Theorem uses Euler characteristic to identify two dimensional topological spaces. Euler Poincare’s Theorem is an alternative way to find Euler characteristic with Betti number, which is topological invariant as well. The objective of this paper is to investigate the homeomorphism of torus 𝑇����� and simplicial complex 𝐾�����. Topological space torus and simplicial complex 𝐾����� have the same Euler characteristic, which is two. Based on Homeomorphy 2-Manifold’s Theorem topological space torus 𝑇����� and simplicial complex 𝐾����� is homeomorphic.
Keyword: simplicial, torus, Euler, homeomorphism, topology