Judul: Biofertilizer Consortium Formulation and Its Application on Corn Plants.
Abstrak: Pupuk hayati merupakan pupuk yang mengandung mikrob hidup yang dapat membantu penyediaan unsur hara yang dibutuhkan untuk pertumbuhan dan perkembangan tanaman. Penelitian ini bertujuan menguji formula pupuk hayati yang berisi konsorsium bakteri non-aktinomiset, cendawan, dan aktinomiset terpilih dengan bahan pembawa cair, berdasarkan kestabilan viabilitas sel mikrob, dan aplikasinya pada tanaman jagung. Uji efektivitas terhadap tanaman jagung dilakukan di rumah kaca menggunakan rancangan acak kelompok satu faktor antara kombinasi dosis pupuk N, P, K dan pupuk hayati dengan tiga ulangan. Isolat yang digunakan yaitu Bacillus thuringiensis SAHA 12.12, Lactobacillus plantarum IN05, Rhizobium sp. R1KG, Sacharomyces cerevisiae L1, Streptomyces sp. A4J, dan Trichoderma sp. T2J yang dikonsorsiumkan dengan bahan pembawa cair. Formula pupuk hayati disimpan selama 8 minggu dan dilakukan uji viabilitas setiap satu bulan selama penyimpanan. Hasil uji menunjukkan viabilitas mikrob menurun setelah disimpan selama delapan minggu dan penurunan paling tinggi pada Streptomyces sp. Aplikasi formula konsorsium pupuk hayati memberikan pengaruh nyata terhadap panjang akar, diameter batang, bobot kering tajuk, bobot tongkol berkelobot, dan bobot biji tongkol. Pemberian formulasi konsorsium hayati kombinasi perlakuan P1M2 (kombinasi 50% pupuk N, P, K dan 100% formulasi pupuk hayati) dapat mengurangi penggunaan N, P, K sebanyak 50% dari dosis rekomendasi., Biofertilizer is a fertilizer that contains live microbes that help the plants to obtain nutrients needed for growth and development. This study aimed to observe the effectiveness of a biofertilizer formula containing a consortium of selected bacteria, fungi, and actinomycetes with liquid carrier materials to maize based on the stability of microbial cell viability and its application. The experiment was conducted in a greenhouse using a randomized block design with one-factor which consisted of a combination of N, P, and K fertilizers and biological fertilizers with three replications. The isolates used in thus experiment were Bacillus thuringiensis SAHA 12.12, Lactobacillus plantarum IN05, Rhizobium sp. R1KG, Saccharomyces cerevisiae L1, Streptomyces sp. A4J, and Trichoderma sp. T2J which were combined as a consortium with liquid carrier material. The formula was stored during 8 weeks, and every weeks was analyzed to observed its viability. The results showed that microbial viability decreased after being stored for eight weeks and the highest decrease was shown by Streptomyces sp. The biofertilizer consortium formula applied to corn significantly influenced the growth and production, including root length, stem diameter, crown dry weight, husk cobs, and cob seed weight. Biological consortium formulations PIM2 can reduce N, P, and K application up to 50% of the recommended dose.
Keyword: aktinomiset, Bacillus, Jagung, Pupuk hayati, Viabilitas

Judul: Efektivitas Pupuk Hayati dari Aktinobakteri sebagai Pemacu Tumbuh pada Tanaman Jagung
Abstrak: Penggunaaan pupuk hayati berpotensi dalam mengurangi penggunaan pupuk sintetik, mengurangi kehilangan unsur hara, dan ramah lingkungan. Aktinobakteri memiliki potensi sebagai pemacu tumbuh tanaman. Namun, kemampuan aktinobakteri dalam meningkatkan pertumbuhan tanaman jagung belum banyak dilaporkan. Penelitian ini bertujuan menguji formulasi pupuk hayati dari aktinobakteri indigenos dan menguji efektivitasnya sebagai pemacu tumbuh tanaman jagung. Penelitian ini disusun berdasarkan Rancangan Acak Kelompok dengan kombinasi perlakuan tiga faktor dengan masing-masing tiga ulangan. Faktor yang digunakan terdiri dari pemberian konsorsium aktinobakteri (A1: dilakukan penambahan, A2: tidak dilakukan penambahan), dosis pupuk NPK (B1: 0 g/pot, B2: 3,6 g/pot, B3: 7,2 g/pot), dan pemberian kompos (C1: tanpa penambahan, C2: dilakukan penambahan). Kombinasi perlakuan pemberian pupuk hayati aktinobakteri (A1), pupuk NPK dosis 3,6 g/pot (B2), dan pemberian kompos (C2) efektif meningkatkan bobot basah akar dan tajuk dan memberikan pertumbuhan terbaik pada tanaman jagung di rumah kaca. Penggunaan pupuk hayati dari aktinobakteri dapat mengurangi penggunaan pupuk NPK sampai 50%., Biological fertilizer can reduce the use of synthetic fertilizers, nutrient loss, and is environmentally friendly. Actinobacteria have potential as growth stimulants. However, the ability of actinobacteria to increase the growth of maize plants has not been widely reported. This research aims to analyze the effect of using biofertilizer formulation from indigenous actinobacteria and its effectiveness as a growth stimulant in maize plants. This study was based on a randomized block design consisting of 3 factors and 3 replications. The factors consisting of the provision of actinobacterial consortium (A1: added, A2: not added), NPK fertilizer dose (B1: 0 g/pot, B2: 3.6 g/pot, B3: 7.2 g/pot), and application of compost (C1: not added, C2: added). The combination of treatment with actinobacterial biofertilizer (A1), NPK fertilizer at a dose of 3.6 g/pot (B2), and compost (C2) effectively increased the wet weight of roots and shoots and provided the best growth for maize in the greenhouse. The use of biological fertilizer from actinobacteria can reduce NPK fertilizer by up to 50%.
Keyword: actinobacteria, biological fertilizer, effectiveness, maize plants

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