Judul: The Effect of Delaying Fertilization Time on Production and Quality of IPB 3S Rice Seeds
Abstrak: Distribusi pupuk subsidi dari pemerintah kepada petani sering mengalami keterlambatan sehingga menyebabkan petani tidak dapat melakukan pemupukan dengan tepat waktu. Penelitian ini bertujuan untuk mengetahui pengaruh penundaan waktu pemupukan terhadap produksi dan mutu benih padi (Oryza sativa L.) varietas IPB 3S. Rancangan yang digunakan dalam penelitian ini adalah rancangan kelompok lengkap teracak (RKLT) satu faktor, yaitu waktu pemupukan yang terdiri atas empat taraf dengan tiga kali ulangan. Taraf pertama atau kontrol adalah waktu pemupukan pada saat 7, 21, dan 35 HST. Taraf kedua terdiri atas waktu pemupukan pada 7, 28, dan 35 HST. Taraf ketiga terdiri atas waktu pemupukan pada 7, 21, dan 42 HST. Taraf keempat terdiri atas waktu pemupukan pada 7, 28, dan 42 HST. Hasil penelitian menunjukkan bahwa penundaan waktu pemupukan selama satu minggu tidak memberikan pengaruh terhadap produksi benih padi varietas IPB 3S, akan tetapi berpengaruh terhadap mutu fisik dan fisiologis benih. Penundaan pemupukan pada fase generatif mampu meningkatkan indeks vigor dan bobot kering kecambah normal, sedangkan penundaan pemupukan pada fase vegetatif dan generatif sekaligus dapat menurunkan bobot 1000 butir benih., The distribution of subsidized fertilizers from the government to farmers is often late. This causes farmers unable to apply fertilizers on time. This study aims to determine the effect of delaying fertilization time on the production and quality of IPB 3S rice seeds. The research used randomized complete block design (RCBD) with one factor. The factor was difference of fertilization time which consist of four levels and three replicates. The first level or the control is the time of fertilization at 7, 21, and 35 DAT. The second level consists of fertilization time at 7, 28, and 35 DAT. The third level consists of fertilization time at 7, 21, and 42 DAT. The fourth level consists of fertilization time at 7, 28, and 42 DAT. The result showed that the delay in fertilization time for one week had no effect on the production of IPB 3S rice seeds, but had an effect on the physical and physiological quality of the seeds. Delaying fertilization in the generative phase can increase the vigor index and dry matter of normal seeds, while delaying fertilization in the vegetative and generative phases simultaneously can reduce the weight of 1000 seeds.
Keyword: fertilizer, NPK, silica, nitrogen, vigor index

Judul: the Effect of Fertilization on Growth and Production of Three Upland Rice Varietes
Abstrak: Padi gogo merupakan budi daya padi di lahan kering. Produktivitas padi gogo masih rendah. Penelitian ini bertujuan mempelajari pengaruh pemupukan pada pertumbuhan dan produksi Tiga Varietas padi lahan kering. Penelitian dilakukan selama 8 bulan yaitu April-Desember 2019 di Kebun Percobaan IPB Sawah Baru. Rancangan yang digunakan adalah Split plot RKLT dua faktor yaitu petak utama dan anak petak. Petak utama terdiri lima taraf yaitu tanpa pupuk (P0), pupuk hayati + pupuk NPK (P1), pupuk NPK (P2), pupuk organik 5 ton ha-1 + pupuk NPK (P3), pupuk organik 5 ton ha-1 d+ pupuk hayati + NPK (P4). Anak petak tiga taraf yaitu IPB 9G (V1), Inpago 10 (V2), dan Timur (V3). Pemupukan berpengaruh nyata terhadap tinggi tanaman, Bagan Warna Daun, jumlah anakan produktif, jumlah gabah hampa dan bobot gabah per rumpun. Varietas berpengaruh nyata terhadap jumlah anakan pada 5-9 MST, jumlah anakan tidak produktif dan jumlah anakan total., Gogo Rice is type of the rice which could be optimized cultivated in dry land. Unfortunately, the Gogo Rice’s productivity is lowest than the others. The aim of this research is to learn the effect of organic fertilizer to the growth and productivity of rice’s genotypes in dry land. The research takes place at Sawah Baru Research Field with 8 months research duration, May 2019-October 2019. The experiment was conducted in split-plot randomized complete block design with two factors, main plot and sub plot. The main plot consists 5 different fertilizers composition which are no fertilizer (P0), the organic fertilizer + NPK Fertilizer(P1), the NPK Fertilizer (P2), 5 tons ha-1 organic fertilizer + NPK Fertilizer (P3), 5 tons ha-1 organic fertilizer + composite fertilizer + and NPK (P4). The sub plot consists IPB 9G (V1), Inpago 10 (V2), and Timur (V3). The fertilization will affect the growth of the rice after 11 weeks planting with the indicator of color leaf, number of productive leaf, amount of empty rice’s grain, and the weight of collective grain. The sub plot gives significant effect on the number of productive for the period 5-9 weeks after planting, the number of unproductive leaf, and amount of total productive leaf. The best interaction between main plot and sub plot is the combination NPK Fertilizer and Organic Fertilizer.
Keyword: grain, panicle, IPB 9G, Timur

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