Tanggap Pertumbuhan dan Perkembangan Jagung Ketan terhadap Pemberian Amelioran dan Pupuk NPK pada Tanah Ultisol

Pengaplikasian jenis bahan organik sebagai amelioran dan pemupukan NPK dapat menambah kesuburan tanah ultisol melalui sifat fisik dan kimia. Tujuan penelitian untuk mempelajari pengaruh jenis amelioran, dosis pupuk NPK serta interaksinya terhadap pertumbuhan dan perkembangan jagung ketan pada tanah ultisol. Pelaksanaan percobaan di Kabupaten Bengkayang, Kalimantan Barat, pada bulan Maret sampai Agustus 2020. Percobaan disusun menggunakan rancangan acak kelompok faktorial. Faktor pertama pemberian jenis amelioran dengan 5 taraf yaitu biocar bonggol jagung, bokasi berangkas jagung, bokasi jerami padi, pupuk kandang sapi, pupuk kandang ayam. Faktor kedua pemberian dosis pupuk NPK dengan 4 taraf yaitu 100, 200, 300, dan 400 kg ha-1. Jenis amelioran pupuk kandang ayam dapat menambah tinggi tanaman 2, 4, dan 6 MST, diameter tongkol, panjang tongkol, bobot per tongkol, dan bobot tongkol per petak. Dosis pupuk NPK yang tebaik untuk produksi jagung ketan yaitu 200 kg ha-1 pada panjang tongkol dan bobot per tongkol, dan dosis 100 kg ha-1 dapat memacu pertumbuhan tanaman yaitu pada tinggi tanaman 4 MST. Kombinasi jenis amelioran dari pupuk kandang ayam dan pupuk NPK 400 kg ha-1 menghasilkan bobot kering akar, bobot kering tajuk,dan laju pertumbuhan relatif yang tertinggi. Kata kunci: bahan organik, kesuburan tanah, produksi tanaman, pupuk anorganikThe application of various types of organic matter as ameliorant and NPK fertilizer can increase the fertility of ultisol soil, physically and chemically. The study aimed to determine the effect of ameliorant types, the dose of NPK fertilizer and their interaction on the growth and development of glutinous corn on ultisol soil. The research was conducted in Bengkayang Regency, West Kalimantan from March to August 2020. The research used a factorial randomized block design. The first factor was the types of ameliorants with 5 levels, namely corncob biochar, corn waste bokashi, rice straw bokashi, cow manure, and chicken manure. The second factor was the dosage of NPK fertilizer with 4 levels, i.e., 100, 200, 300, and 400 kg ha-1. The chicken manure ameliorant increased plant height 2, 4, and 6 WAP (weeks after planting), ear diameter, ear length, ear weight per ear, and ear weight per plot. The best dose of NPK fertilizer for glutinous maize production is 200 kg ha-1 on ear length and weight per ear, and a dose of 100 kg ha-1 can stimulate plant growth based on plant height of 4 WAP. The combination of chicken manure and NPK fertilizer of 400 kg ha-1 produced the highest root dry weight, crown dry weight, and relative growth rate. Keywords: crop production, inorganic fertilizers, organic matter, soil fertilit