Judul: Growth and Productivity of Soybean with Phosphate Fertilization Dose and Frequency on Saturated Soil Culture in Tidal Swamp
Abstrak: Konsumsi kedelai di Indonesia tahun 2020 mencapai 2,87 juta ton, sedangkan produksi nasional hanya 613.300 ton karena luas lahan kedelai menurun akibat persaingan komoditas dan perubahan lahan pertanian. Lahan pasang surut menjadi alternatif peningkatan areal pertanian menggunakan teknik budidaya jenuh air. Penelitian bertujuan mempelajari dosis dan frekuensi pemupukan P terhadap pertumbuhan dan produktivitas kedelai dengan budidaya jenuh air di lahan pasang surut. Penelitian menggunakan rancangan kelompok lengkap teracak faktorial dengan dua faktor dan tiga ulangan. Faktor pertama adalah dosis pupuk P terdiri atas: 36, 72, dan 108 kg P2O5 ha-1 (180, 360, dan 540 kg Fertiphos ha-1). Faktor kedua adalah frekuensi pemupukan P terdiri atas; pada saat tanam 0 hari setelah tanam (HST), 0 dan 30 HST, dan 0, 30, 60 HST. Perlakuan berbagai dosis pemupukan fosfat berpengaruh nyata terhadap peningkatan tinggi tanaman, jumlah cabang, jumlah daun, luas daun, bobot basah batang, bobot kering batang, bobot kering daun, jumlah polong isi, jumlah polong hampa, bobot biji ubinan, dan produktivitas. Perlakuan berbagai frekuensi pemupukan fosfat berpengaruh nyata terhadap peningkatan tinggi tanaman, jumlah cabang, jumlah bintil akar, jumlah polong isi, dan jumlah polong hampa. Dosis pupuk 108 kg P2O5 dan frekuensi pemupukan fosfat dengan tiga kali pemupkan pada 0, 30, dan 60 HST menjadi kombinasi terbaik untuk peningkatan produksi kedelai. Dosis pupuk 108 kg P2O5 ha-1 menghasilkan produksi kedelai tertinggi sebesar 2,60 ton ha-1., Indonesia's soybean consumption is estimated to reach 2.87 million tons in 2020. Meanwhile, the national production is only 613,300 tons as the soybean area is decreasing due to commodity competition and agricultural land changes. Tidal land is an alternative to increase agricultural area using water-saturated cultivation techniques. The research aimed to study the dose and frequency of P fertilization on the growth and productivity of soybean plants with water-saturated cultivation on tidal land. The study used a factorial randomized complete block design with two factors and three replications. The first factor was the dose of P fertilizer consisting of: 36, 72, and 108 kg P2O5 ha-1 (180, 360, and 540 kg Fertiphos ha-1). The second factor is the frequency of P fertilization consisting of; at planting 0 days after planting (DAP), 0 and 30 DAP, and 0, 30, and 60 DAP. The treatment of various doses of phosphate fertilization had a significant effect on increasing plant height, branch number, leaf number, leaf area, stem fresh weight, stem dry weight, leaf dry weight, number of filled pod number, number of empty pods, seed weight, and productivity. The treatment of various phosphate fertilization frequencies significantly increased plant height, number of branches, number of root nodules, number of filled pods, and number of empty pods. The fertilizer dose of 108 kg P2O5 ha-1 and phosphate fertilization frequency at 0, 30, and 60 DAP the best combination for increasing soybean production. The fertilizer dose of 108 kg P2O5 ha-1 resulted in the highest soybean seed yield as much as 2.60 tons ha-1.
Keyword: Fosfor, Lahan rawa, Varietas Demas 1, Phosphorus, swamplands