Pengaruh Inhibitor Nitrifikasi Dicyandiamide dan Pengurangan Dosis Pupuk Urea terhadap Serapan Nitrogen, Pertumbuhan dan Produktivitas Tanaman Padi (Oryza sativa L.)
kridha widi yuwana, Ir. Budiastuti Kurniasih, M.Sc., Ph.D.
2026 | Tesis | S2 Agronomi
Penelitian ini bertujuan untuk mengevaluasi pengaruh inhibitor nitrifikasi dicyandiamide (DCD) dan pengurangan dosis pupuk urea terhadap serapan nitrogen, pertumbuhan, dan produktivitas padi varietas Gamagora 7. Percobaan menggunakan Rancangan Acak Kelompok Lengkap (RAKL) faktorial dengan lima aras dosis urea (0%, 25%, 50%, 75%, dan 100?ri rekomendasi 300 kg ha?¹) dan dua aras DCD (0 dan 15 kg ha?¹) pada media tanam berpasir berkapasitas pertukaran kation rendah (6,75 cmol(+) kg?¹). Hasil menunjukkan bahwa DCD 15 kg ha?¹ secara mandiri meningkatkan bobot kering total sebesar 10%, dan jumlah malai sebesar 13,68%. Dosis urea 75% (225 kg ha?¹) menghasilkan pertumbuhan dan produktivitas tertinggi. Kombinasi DCD dengan urea 75% (P3N1) memberikan hasil terbaik dengan meningkatkan serapan N tanaman 27%, kandungan N jaringan 33%, sifat fisiologis 20?n menghasilkan gabah kering giling (GKG) tertinggi sebesar 6,22 ton ha?¹, melampaui dosis urea penuh tanpa DCD (4,06 ton ha?¹) dengan peningkatan sebesar 53,20%. Penggunaan DCD pada dosis urea 100% justru menurunkan GKG hingga 1,29 ton ha?¹ akibat toksisitas NH??. Disimpulkan bahwa kombinasi DCD 15 kg ha?¹ dengan urea 75% merupakan strategi pemupukan nitrogen optimal pada tanah berpasir KPK rendah untuk varietas Gamagora 7.
This study aimed to evaluate the effects of the nitrification inhibitor dicyandiamide (DCD) and reduced urea fertilizer doses on nitrogen uptake, growth, and productivity of the Gamagora 7 rice variety. The experiment used a factorial completely randomized block design (CRBD) with five urea dose levels (0%, 25%, 50%, 75%, and 100% of the recommended rate of 300 kg ha?¹) and two DCD levels (0 and 15 kg ha?¹) on a sandy growing medium with low cation exchange capacity (6.75 cmol(+) kg?¹). The results showed that DCD at 15 kg ha?¹ alone increased total dry weight by 10% and the number of panicles by 13.68%. A urea dose of 75% (225 kg ha?¹) produced the highest growth and productivity. The combination of DCD with 75% urea (P3N1) yielded the best results by increasing plant N uptake by 27%, tissue N content by 33%, and physiological traits by 20%, and produced the highest dry milled grain yield of 6.22 metric tons ha?¹, surpassing the full urea dose without DCD (4.06 metric tons ha?¹) by 53.20%. The use of DCD at a 100% urea dose actually reduced GKG by 1.29 metric tons ha?¹ due to NH?? toxicity. It is concluded that the combination of 15 kg ha?¹ of DCD with 75% urea is the optimal nitrogen fertilization strategy on low-KPK sandy soils for the Gamagora 7 variety.
Kata Kunci : padi, nitrifikasi inhibitor, dicyandiamide (DCD), dosis pupuk urea
