RINGKASAN ZULKARNAINI. Pengaruh Penggunaan Pupuk Organik dan Anorganik terhadap Perubahan Sifat Kimia Tanah, Pertumbuhan dan Hasil Beberapa Varietas Padi (Oryza sativa L.) di bawah bimbingan Bakhtiar sebagai pembimbing ketua dan Sabaruddin sebagai pembimbing anggota. Penelitian ini bertujuan untuk mengetahui pengaruh penggunaan pupuk organik dan anorganik terhadap perubahan sifat kimia tanah, pertumbuhan dan produktivitas beberapa varietas padi, serta interaksinya. Penelitian ini dilaksanakan di lahan sawah petani Desa Geulanggang Kulam Kecamatan Kota Juang Kabupaten Bireuen, mulai bulan Juni sampai Desember 2016. Analisis terhadap tanah dan tanaman dilaksanakan di Laboratorium Penelitian Tanah dan Tanaman Fakultas Pertanian Universitas Syiah Kuala, Darussalam, Banda Aceh. Varietas yang digunakan dalam penelitian ini adalah benih padi varietas Batu Tegi, Situ Bagedit, Situ Patenggang dan Inpari 30. Penelitian ini menggunakan rancangan acak kelompok (RAK) pola faktorial dengan 3 ulangan. Ada dua faktor yang diteliti yaitu kombinasi pupuk organik dan anorganik (P) terdiri atas: P Urea + 150 kg ha -1 SP-36 + 100 kg ha -1 KCl, P 0 = 0 ha 1 -1 pupuk organik + 250 kg ha = 5 ton ha -1 pupuk organik + 225 kg ha -1 Urea + 125 kg ha -1 SP-36 +75 kg ha -1 KCl, P 2 = 10 ton ha -1 pupuk organik + 200 kg ha -1 Urea + 100 kg ha -1 SP-36 + 50 kg ha -1 KCl, P 3 = 15 ton ha -1 pupuk organik + 175kg ha -1 Urea + 75 kg ha -1 SP-36 + 25 kg ha -1 KCl. Faktor kedua adalah Varietas (V) terdiri atas: V 1 = Batu Tegi, V 2 = Situ Bagendit, V 3 = Situ Patenggang, V = Inpari 30. Peubah yang diamati meliputi C-organik, pH, N-total, P-tersedia, K-tersedia, KTK, dan kejenuhan basa, tinggi tanaman dan jumlah anakan per rumpun pada umur 2, 3, 4, 5, 6, 7, 8 dan 9 Minggu Setelah Tanam (MST); jumlah anakan produktif per rumpun; umur berbunga; panjang malai; persentase gabah bernas dan gabah hampa; bobot 1000 butir gabah; berat gabah kering per plot dan hasil per hektar. Hasil penelitian menunjukkan bahwa perlakuan kombinasi pupuk organik dan anorganik dapat meningkatkan C-organik, KTK, P-tersedia, dan K tersedia. Perlakuan kombinasi pupuk organik dan anorganik belum mampu meningkatkan pertumbuhan komponen hasil dan hasil padi. Hasil padi pada perlakuan 5 ton ha -1 pupuk organik + 225 kg ha -1 Urea + 125 kg ha -1 SP-36 + 75 kg ha -1 KCl mencapai 7,00 ton ha . Hasil varietas Inpari 30 menghasilkan produksi mencapai 7,29 ton ha -1 yang tidak berbeda nyata dari varietas Situ Bagendit dan Situ Patenggang. Kata Kunci: Pupuk Organik, Anorganik, Varietas Padi. 4 -1 -1 SUMMARY ZULKARNAINI. Effect of application organic and inorganic fertilizers on changes in soil chemical properties, growth and productivity of several rice varieties (Oryza sativa L.) under the supervision of Bakhtiar and Sabaruddin. The purpose of this study was to determine the effect of the combination of organic and inorganic fertilizers on the change of soil chemical properties, growth and yield of several rice varieties. The study was conducted in farmer rice fields in Bireuen Districts, Aceh Province from June to December 2016. Analysis of the soil and plant was carried out in the laboratory of the Faculty of Agriculture, University Syiah Kuala, Banda Aceh. Factorial pattern of Randomized block design (RBD) with 3 replications was used in this study. The first factor of the treatment consist of 4 levels combination of organic and inorganic fertilizers as follows P = without organic fertilizers + 250 kg ha -1 Urea + 150 kg ha organic fertilizers + 225 kg ha -1 -1 SP-36 + 100 kg ha Urea + 125 kg ha -1 0 -1 KCl, P SP-36 + 75 kg ha =10 ton ha -1 organic fertilizers + 200 kg ha = 15 ton ha -1 -1 organic fertilizers + 175 kg ha Urea + 100 kg ha -1 -1 -1 1 SP-36 + 50 kg ha Urea + 75 kg ha -1 = 5 ton ha KCl, P -1 2 KCl, P SP-36 + 25 kg ha KCl. The second factor of the treatment consists of 4 rice varieties as follows Batutegi, Situ Bagendit, Situ Patenggang and Inpari 30. Variables observed included C-organic, pH, total nitrogen, P-available, K-available, cation exchange capacity (CEC), and base saturation, plant height and number of tillers at 2,3,4,5,6,7,8 and 9 Weeks After Planting (WAP); number of productive tillers; heading date; panicle length; percentage of filled grain and empty grain; 1000 grain weight; dry grain weight per plot and yields. The results showed that the treatment combination of organic and inorganic fertilizers increased C-organic, CEC, P-available, and Kavailable. The combination treatment of organic and inorganic fertilizers has not been able to improve plant growth, yield components, and rice yields. Rice yields in 5 ton ha -1 organic fertilizers + 225 kg ha -1 Urea + 125 kg ha -1 SP-36 + 75 kg ha KCl treatment was reached 7.00 tons ha -1 . Yields of Inpari 30 variety reached 7.29 tons ha -1 , which is not significantly different from Situ Bagendit and Situ Patenggang varieties. Key words: Organic fertilizer, inorganic fertilizer, rice varieties -1 -1 3 -1