Judul: The effect of Dose and Application Method of Lime and Manure of Soybean (Glycine max L. Merr.) with Saturated Soil Culture System on Tidal Swap Land
Abstrak: Kebutuhan kedelai di Indonesia terus meningkat setiap tahunnya seiring dengan meningkatnya jumlah penduduk Indonesia. Pemenuhan kebutuhan kedelai Indonesia masih terpenuhi lewat impor sebesar 2,58 juta ton per tahun. Produksi kedelai dapat ditingkatkan melalui salah satunya pemanfaatan lahan rawa dengan pemberian kapur dan pupuk kandang yang dipadukan dengan cara penempatannya, baik secara sebar maupun di dalam lubang tanam dengan memanfaatkan teknologi budidaya jenuh air. Penelitian ini bertujuan mempelajari pengaruh dosis dan cara pemberian kapur dan pupuk kandang, serta kombinasi yang tepat terhadap pertumbuhan dan produksi kedelai dengan sistem budidaya jenuh air. Penelitian dilaksanakan di Desa Karyabakti, Kecamatan Rantau Rasau, Kabupaten Tanjung Jabung Timur, Provinsi Jambi. Rancangan yang digunakan adalah Rancangan Kelompok Lengkap Teracak (RKLT) faktorial dengan dua faktor, yaitu faktor pertama berupa kombinasi dosis kapur dan pupuk kandang (0+0, 500+500, 1000+1000, dan 1500+1500 kg ha-1), dan faktor kedua berupa cara pemberian kapur dan pupuk kandang (sebar dan di dalam lubang tanam) dengan tiga ulangan. Hasil menunjukkan bahwa pemberian kapur 1500 kg ha-1 dan pupuk kandang 1500 kg ha-1 yang dikombinasikan dengan pemberian kapur dan pupuk kandang di dalam lubang tanam secara nyata memberikan hasil terbaik dengan produktivitas kedelai mencapai 3,127 ton ha-1., Indonesia's soybeans needs increases every year along with the increasing population of Indonesia. Indonesia's soybean needs are still met through imports of 2,58 million tons per year. Soybean production can be increased by using swap land by giving lime and manure combined by its application method, both in distribution and inside the planting holes by utilizing water-saturated soil culture technology. This study proposed to study the effect of the dose and application method of lime and manure, as well as the right combination on the growth and production of soybeans with a water-saturated soil culture system. The research was conducted in Karyabakti Village, Rantau Rasau District, East Tanjung Jabung Regency, Jambi Province. The research design was a factorial Randomized Complete Block Design (RCBD), the first factor was the dose of lime and manure (0+0, 500+500, 1000+1000, and 1500+1500 kgs ha-1), and the second factor was the method of placing lime and manure (spread and inside the planting holes) with three replications. The results showed that 1500 kgs ha-1 lime dose and manure fertilization dose of 1500 kgs ha-1 combined with lime and manure in the planting hole actually gave the best results with soybean productivity reaching 3,127 tons ha-1.
Keyword: sebar, lubang tanam, produktivitas, spred, planting hole, productivity

Judul: Growth and Productivity of Soybean with Phosphate Fertilization Dose and Frequency on Saturated Soil Culture in Tidal Swamp
Abstrak: Konsumsi kedelai di Indonesia tahun 2020 mencapai 2,87 juta ton, sedangkan produksi nasional hanya 613.300 ton karena luas lahan kedelai menurun akibat persaingan komoditas dan perubahan lahan pertanian. Lahan pasang surut menjadi alternatif peningkatan areal pertanian menggunakan teknik budidaya jenuh air. Penelitian bertujuan mempelajari dosis dan frekuensi pemupukan P terhadap pertumbuhan dan produktivitas kedelai dengan budidaya jenuh air di lahan pasang surut. Penelitian menggunakan rancangan kelompok lengkap teracak faktorial dengan dua faktor dan tiga ulangan. Faktor pertama adalah dosis pupuk P terdiri atas: 36, 72, dan 108 kg P2O5 ha-1 (180, 360, dan 540 kg Fertiphos ha-1). Faktor kedua adalah frekuensi pemupukan P terdiri atas; pada saat tanam 0 hari setelah tanam (HST), 0 dan 30 HST, dan 0, 30, 60 HST. Perlakuan berbagai dosis pemupukan fosfat berpengaruh nyata terhadap peningkatan tinggi tanaman, jumlah cabang, jumlah daun, luas daun, bobot basah batang, bobot kering batang, bobot kering daun, jumlah polong isi, jumlah polong hampa, bobot biji ubinan, dan produktivitas. Perlakuan berbagai frekuensi pemupukan fosfat berpengaruh nyata terhadap peningkatan tinggi tanaman, jumlah cabang, jumlah bintil akar, jumlah polong isi, dan jumlah polong hampa. Dosis pupuk 108 kg P2O5 dan frekuensi pemupukan fosfat dengan tiga kali pemupkan pada 0, 30, dan 60 HST menjadi kombinasi terbaik untuk peningkatan produksi kedelai. Dosis pupuk 108 kg P2O5 ha-1 menghasilkan produksi kedelai tertinggi sebesar 2,60 ton ha-1., Indonesia's soybean consumption is estimated to reach 2.87 million tons in 2020. Meanwhile, the national production is only 613,300 tons as the soybean area is decreasing due to commodity competition and agricultural land changes. Tidal land is an alternative to increase agricultural area using water-saturated cultivation techniques. The research aimed to study the dose and frequency of P fertilization on the growth and productivity of soybean plants with water-saturated cultivation on tidal land. The study used a factorial randomized complete block design with two factors and three replications. The first factor was the dose of P fertilizer consisting of: 36, 72, and 108 kg P2O5 ha-1 (180, 360, and 540 kg Fertiphos ha-1). The second factor is the frequency of P fertilization consisting of; at planting 0 days after planting (DAP), 0 and 30 DAP, and 0, 30, and 60 DAP. The treatment of various doses of phosphate fertilization had a significant effect on increasing plant height, branch number, leaf number, leaf area, stem fresh weight, stem dry weight, leaf dry weight, number of filled pod number, number of empty pods, seed weight, and productivity. The treatment of various phosphate fertilization frequencies significantly increased plant height, number of branches, number of root nodules, number of filled pods, and number of empty pods. The fertilizer dose of 108 kg P2O5 ha-1 and phosphate fertilization frequency at 0, 30, and 60 DAP the best combination for increasing soybean production. The fertilizer dose of 108 kg P2O5 ha-1 resulted in the highest soybean seed yield as much as 2.60 tons ha-1.
Keyword: Fosfor, Lahan rawa, Varietas Demas 1, Phosphorus, swamplands

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