Judul: Pemanfaatan Pupuk Kandang Ayam dan Fungi Mikoriza Arbuskula untuk Memperbaiki Pertumbuhan Bibit Jeruk Siam
Abstrak: The experiment was conducted to study the effects of manure, vasicular arbuscular michorizae (VAM) and their interaction on the growth of siam citrus seedling. The experiment was conducted at Kacinambun village, Karo, North Sumatera in Maret-Juli 2012. Experiment using Randomized Completely Block Design two factors. First factor was manure: 0 g, 250 g, and 500 g manure plant-1 and the second factor was VAM: 0 g, 5 g, 10 g, and 15 g VAM plant-1. The results showed that the manure at 500 g plant-1 showed better for number of branch, number of leaf, shoot dry weight, and leaf P concentration. VAM increase the percentage of root colonizations and leaf P concentration. Interaction of 250 g manure plant-1 and 15 g VAM plant-1 showed better result for the leaf P concentration.
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Judul: Pengaruh Inokulasi Mikoriza Arbuskular dan Pupuk Kandang Sapi terhadap Pertumbuhan Semai Kayu Putih (Melaleuca cajuputi) di Tanah Pascatambang Batu Kapur
Abstrak: Tanah pascatambang kapur memiliki kesuburan yang rendah sehingga proses revegetasi akan terhambat. Penambahan amelioran tanah dan pemilihan tanaman yang tepat diperlukan agar revegetasi berhasil dengan baik. Penggunaan Fungi Mikoriza Arbuskular (FMA) dan pupuk kandang sapi diharapkan dapat membantu pertumbuhan tanaman pada tanah pascatambang batu kapur. Tujuan penelitian ini adalah (1) menganalisis pengaruh interaksi FMA dan pupuk kandang sapi terhadap pertumbuhan tanaman kayu putih di tanah pascatambang kapur, (2) menganalisis dosis pupuk kandang yang optimal dalam meningkatkan pertumbuhan kayu putih. Penelitian ini menggunakan rancangan acak lengkap (RAL) dengan dua faktor perlakuan (mikoriza dan pupuk kandang sapi). Hasil penelitian menunjukkan bahwa tidak ada pengaruh dari interaksi antara inokulasi FMA dengan pupuk kandang sapi. Pemberian FMA secara tunggal juga tidak berpengaruh secara nyata terhadap pertumbuhan semai kayu putih. Sementara faktor tunggal pupuk kandang sapi berpengaruh nyata pada pertumbuhan semai, dosis terbaik pupuk kandang sapi yaitu 15% yang dapat meningkatkan pertumbuhan tinggi dan diameter masingmasing sebesar 28,04% dan 38,41% dibanding tanaman kontrol., Post-mining soil has low fertility so that the revegetation process will be hampered. The addition of soil ameliorants and proper plant selection are necessary for successful revegetation. The use of Arbuscular Mycorrhizal Fungi (AMF) and cow manure is expected to help plant growth on post-limestone mining soil. The aims of this study were (1) to analyze the interaction effect of AMF and cow manure on the growth of eucalyptus plants in post-lime mining soil, (2) to analyze the optimal dose of manure in increasing eucalyptus growth. This study used a completely randomized design (CRD) with two treatment factors (mycorrhizae and cow manure). The results showed that there was no effect of the interaction between AMF inoculation with cow manure. Giving AMF alone also did not significantly affect the growth of eucalyptus seedlings. While the single factor of cow manure had a significant effect on seedling growth, the best dose of cow manure was 15% which could increase growth in height and diameter by 28,04% and 38,41%, respectively, compared to control plants.
Keyword: Eucalyptus, Mycorrhiza, Cow Manure, Post-mining Lime Soil

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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