PENINGKATAN HASIL PADI DAN Zn BERAS MELALUI REKAYASA TEKNOLOGI BUDIDAYA

YUSTISIA, IR.,M.SI., Prof. Dr. Ir. Tohari, M.Sc.; Dr. Ir. Dja’far Shiddieq, M.Sc; Dr. Subowo, G., MS

2015 | Tesis | S3 Agronomi

Konsumsi beras berkadar Zn rendah dapat mengakibatkan defisiensi nutrisi Zn pada manusia. Penyebab kadar Zn beras rendah antara lain teknologi budidaya padi yang dihasilkan dan implementasinya oleh petani lebih berorientasi pada peningkatan hasil. Hal tersebut terjadi akibat dilution effect. Permasalahan tersebut dapat diatasi melalui reorientasi penelitian pada peningkatan hasil dan kadar Zn beras. Inovasi teknologi budidaya yang diperlukan untuk mendukung upaya tersebut antara lain pemilihan varietas serta pemupukan anorganik (N, P dan K) dan pemupukan organik yang berimbang. Penelitian bertujuan untuk (1) mendapatkan karakter fisiologis varietas unggul berdaya hasil tinggi di Vertisol dan Inceptisol, (2.a) mendapatkan unsur hara defisien dan pengaruhnya terhadap kadar serta nisbah hara tanaman di Inceptisol pada varietas unggul padi, dan (2.b) mempelajari dan mendapatkan teknologi pupuk N, P dan K dosis petani dan nisbah hara yang mempunyai hubungan positif dengan hasil gabah dan Zn beras, (3) mempelajari pengaruh dan mendapatkan teknologi pupuk anorganik berimbang yang dapat meningkatkan proses fisiologis, pertumbuhan, hasil gabah dan Zn beras di Inceptisol pada varietas unggul padi, dan (4) mempelajari pengaruh dan mendapatkan teknologi pupuk organik berimbang yang dapat meningkatkan hasil gabah dan Zn beras di Inceptisol pada varietas unggul padi. Penelitian dilaksanakan melalui 4 tahap percobaan. Percobaan pot (Percobaan I-III) dilaksanakan di Rumah Kaca Fakultas Pertanian Universitas Gadjah Mada. Percobaan lapangan (Percobaan IV) dilaksanakan pada lahan Petani Desa Trirenggo, Kabupaten Bantul, Yogyakarta. Percobaan I-IV dilaksanakan pada Juli 2008-Mei 2011. Hasil Percobaan I-IV menunjukkan: (1) karakter fisologis varietas padi unggul berdaya hasil tinggi di Vertisol dan Inceptisol pada teknologi N, P dan K dosis petani adalah nisbah Mn/K daun dan nisbah N/K daun tinggi. Varietas padi unggul berkadar Zn beras tinggi di Vertisol dan Inceptisol adalah luas daun (LD) stadia keluar malai (KM) rendah, SPAD KM tinggi, protein daun tinggi, N/Mg daun tinggi, Fe daun rendah, indeks efisiensi hasil biji (IEHB) tinggi dan penurunan hasil rendah, (2.a) Inceptisol defisien unsur hara N sehingga hasil padi tanpa dipupuk N (0N, + PK) rendah akibat kadar N jerami rendah, K jerami tinggi dan nisbah N/K jerami tinggi, (2.b) nisbah N/K jerami mempunyai hubungan positif dengan hasil gabah dan Zn beras pada teknologi pupuk petani 222,26 kg N/ha, 0 kg P2O5/ha dan 47,67 kg K2O/ha (0P, +NK), (3) teknologi pupuk anorganik berimbang yang dapat meningkatkan proses fisiologis, pertumbuhan, hasil gabah dan Zn beras di Inceptisol adalah kombinasi P1 (25,14 kg N/ha, 0 kg P2O5/ha dan 75,85 kg K2O/ha), kombinasi 100-300% P1 dan kombinasi 222,26 kg N/ha, 56,80 kg P2O5/ha dan 0 kg K2O/ha), dan (4) teknologi kombinasi pupuk anorganik dan pupuk organik yang dapat meningkatkan hasil gabah dan Zn beras di Inceptisol adalah: (1) pupuk anorganik 222,26 kg N/ha, 56,80 kg P2O5/ha dan 0 kg K2O/ha), (2) pupuk organik kompos jerami 2 t/ha, dan (3) varietas alternatif Ciherang atau Cimelati. Implementasi teknologi rekayasa yang dihasilkan dari penelitian ini memberikan hasil gabah 7,75 t/ha, hasil beras 4,661 t/ha, kandungan Zn beras 0,0837 kg/ha dan efisiensi agronomi 13,10 kg hasil/kg input NPK total.

Low consumption of rice containing Zinc (Zn) may lead to the deficiency of Zn nutrition in human body. The factor that makes the low concentration of Zn in rice is among others the rice farming technology and its implementation by farmers which is more oriented on how to increase grain yield. This is caused by the dilution effect. This issue can be solved through the research reorientation on the increases of grain yield and increases of grain Zn concentration. Farming technology innovation needed in order to support these efforts is among others, the selection of rice varieties and inorganic fertilizer (N, P and K) and well-adjusted organic fertilizer. This study aims to (1) obtain physiological character of high yielding variety with high grain yield in Vertisols and Inceptisols, (2.a) obtain nutrient deficient on soil-rice varieties and its influence on the nutrient concentration and nutrient ratios of rice varieties in Inceptisols, and (2.b) examine and obtain the technology of N, P and K fertilizer according to the dose benefited by farmers as well as the nutritive value which has positive correlation with the grain yield and grain Zn concentration of rice, (3) examine the influence and obtain the technology of well-adjusted inorganic fertilizer which is able to improve the physiological process, growth, grain yield and grain Zn concentration of rice varieties in Inceptisols, and (4) examine the influence and obtain well-adjusted organic fertilizer which is able to improve the grain yield and grain Zn concentration of rice varieties in Inceptisolss. The study was conducted through four experiment stages. Pot experiment (Experiment I-III) was conducted in the Glass House in the Faculty of Agriculture of Universitas Gadjah Mada. Field experiment (Experiment IV) was conducted on the lowland in Trirenggo Village, Bantul District, Yogyakarta. Experiment I-IV was conducted during July 2008- May 2011. The results of the Experiment I-IV indicated: (1) the physiological character of rice variety which has high grain yield in Vertisols and Inceptisols in of N, P and K farmer’s dose is the high Mn/K leaf ratio and high N/K leaf ratio. The physiological character of rice variety containing high grain Zn concentration in Vertisols and Inceptisols is the low leaf area (LA) and high SPAD value at heading stage (HS), high leaf protein, high N/Mg leaf, low Fe leaf, high grain yield efficiency index (GYEI) and low grain yield decreases, (2.a) N nutrient deficient in Inceptisols cause the low grain yield in (0N, + PK) treatment. Its affect the low N concentration in straw, high K concentration in straw and high N/K ratio in straw, (2.b) N/K ratio in straw has positive correlation with the grain yield and grain Zn concentration towards farmers fertilization technology 222.26 kg N/ha, 0 kg P2O5/ha and 47.67 kg K2O/ha (0P, +NK), (3) the technology of well-adjusted inorganic fertilizer which is able to improve the physiological process, plant growth, grain yield and grain Zn in Inceptisols is the combination of P1 (25.14 kg N/ha, 0 kg P2O5/ha and75.85 kg K2O/ha), of 100-300% P1 and of 222.26 kg N/ha, 56.80 kg P2O5/ha and 0 kg K2O/ha), and (4) combined technology of inorganic and organic fertilizer which is able to improve the grain yield and grain Zn in Inceptisols is: (1) inorganic fertilizer at 222.26 kg N/ha, 56.80 kg P2O5/ha and 0 kg K2O/ha), (2) straw organic compost at 2 t/ha, and (3) alternative variety of Ciherang or Cimelati. The implementation of engineering technology, which is resulted from the study, generated grain yield of 7.75 t/ha, grain rice of 4.661 t/ha, rice Zn content of 0.0837 kg/ha and agronomic efficiency of 13.10 yield/kg of total NPK input.

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