Judul: Pengendalian gulma pada tanaman padi sawah dengan menggunakan herbisida berbahan aktif Bentazon dan MCPA
Abstrak: Weeds are one of major problem in rice intensification. The objective of this research was to observe the effectiveness of bentazon and MCPA as mixed herbicide to control weeds in rice. The experiment was conducted at Bojong Jengkol village, Ciampea district, Bogor regency, West Java from September 2012 until January 2013. This research was arranged in Randomized Block Design with single factor, seven treatments and four replications. The treatments consist of seven treatments with five dosages of herbicide (i.e.: 1.00 L ha-1, 1.50 L ha-1, 2.00 L ha-1, 2.50 L ha-1, and 3.00 L ha-1), conventional weeding (at third and sixth week after transplanted) and no weeding. The result showed that bentazon-MCPA application could control sedges (Fimbristylis miliacea and Cyperus iria) and broadleaf (Ludwigia octovalvis, Alternanthera philoxeroides, and Portulaca oleracea) weeds. Application of bentazon-MCPA caused light-fair toxicity symptomps on rice plants until 2 weeks after application and decreased empty grain percentage about 6-10 % compared with no weeding treatment also increased rice yield productivity about 48.6% and that was not significantly different compared with conventional weeding.
Keyword: Bogor Agricultural University (IPB), weed in rice, weed control, Bentazon & MCPA

Judul: Effectiveness of Nutsedge (Cyperus rotundus L.) as Bioherbicide to Control Some Weed Species in Lowland Rice
Abstrak: Lahan tanaman padi di Indonesia yang luas masih belum bisa mencukupi kebutuhan pangan dalam negeri. Salah satu faktor penyebabnya adalah persaingan antara tanaman padi dan gulma. Inovasi yang dapat diterapkan dalam pengendalian gulma adalah aplikasi bioherbisida. Bioherbisida yang digunakan adalah bioherbisida dari senyawa alelopati yang dihasilkan tumbuhan. Senyawa alelopati dapat menekan bahkan mematikan tumbuhan lain di sekitarnya. Salah satu tumbuhan yang dapat dimanfaatkan untuk menjadi bahan baku bioherbisida adalah gulma teki (Cyperus rotundus L.). Penelitian ini bertujuan untuk mengetahui efektivitas bioherbisida berbahan baku teki pada lahan pertanaman padi sawah. Rancangan percobaan yang digunakan adalah rancangan kelompok lengkap teracak (RKLT) faktor tunggal dan tiga ulangan. Perlakuan terdiri dari kontrol (P0), pengendalian manual (P1), bioherbisida granul 22,5 kg tepung ha-1(P2), bioherbisida granul 45 kg tepung ha-1(P3), bioherbisida granul 67,5 kg tepung ha-1(P4), bioherbisida larutan 45 kg tepung ha-1(P5), herbisida pratumbuh Oksifluorfen 2 l ha-1(P6). Hasil percobaan menunjukan bahwa aplikasi bioherbisida teki formulasi granul dosis 67,5 kg ha-1dapat menekan pertumbuhan gulma Ludwigia octovalvis, Pistia stratiotes, dan Paspalum distichum dibandingkan dengan perlakuan tanpa penyiangan di lahan pertanaman padi. Aplikasi bioherbisida teki dapat meningkatkan hasil panen dan tidak menimbulkan fitotoksisitas terhadap tanamanpadi. Kata kunci : alelopati, bioherbisida, gulma, padi sawah, teki, Competition between weeds and rice is one of factors that decreasing rice productivity. An innovation that can be applied in weed control is the application of bioherbicides. The bioherbicide is usualy made of allelopathic compounds produced by plants. Allelopathic compounds can suppress some weeds. One of the plants that can be used as raw material for bioherbicides is nutsedge weed (Cyperus rotundus L.). The objective of the research was to determine the effectiveness of bioherbicide made from nutsedges (Cyperus rotundus L.) in rice fields. The experiment was designed as randomized complete block design with single factor and three replications. The treatments were without weeding (P0), manual weeding (P1), granule bioherbicide from nutsedge 22,5 kg ha-1(P2), 45 kg ha-1(P3), 67,5 kg ha-1(P4), solution bioherbicide 45 kg ha-1(P5), and Oxyfluorfen herbicide 2 l ha-1(P6). The results of the experiment showed that the application of bioherbicide with granule formulations at 67,5 kg ha-1could suppress the growth of Ludwigia octovalvis, Pistia stratiotes, and Paspalum distichum weeds compared to the without weeding treatment. The application of bioherbicide made from nutsedge could increase crop yields and did not cause fitotoxicity to rice plants. Keywords: allelopathy, bioherbicide, lowland rice, sedge, weed
Keyword: allelopathy, bioherbicide, lowland rice, sedge, weed

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