Aplikasi pupuk hayati ameliorant, dan pupuk NPK terhadap N total, P tersedia serta pertumbuhan dan hasil jagung pada inceptisols

Inceptisols umumnya memiliki tingkat kesuburan tanah rendah sampai sedang. Upaya peningkatan ketersediaan hara tanah Inceptisol dengan pupuk anorganik NPK perlu diimbangi dengan aplikasi pupuk hayati dan amelioran organik. Percobaan ini bertujuan untuk mengurangi dosis pupuk NPK dengan menggunakan pupuk hayati dan amelioran organik serta meningkatkan hasil tanaman jagung. Percobaan dilakukan di Pasir Banteng, Kabupaten Sumedang. Penelitian menggunakan RAK faktorial. Pupuk hayati dengan amelioran organik sebagai faktor pertama sebanyak empat taraf: tanpa pupuk hayati dan amelioran (kontrol), diberi pupuk hayati, amelioran organik, dan gabungan keduanya. Faktor kedua yaitu dosis pupuk NPK empat taraf: 100%, 80%, 60%, 40% NPK dosis anjuran.  Dilakukan tiga kali ulangan. Hasil penelitian menunjukkan terdapat interaksi antara pupuk hayati, amelioran organik, dengan pupuk NPK terhadap tinggi tanaman, N-total tanah, bobot tongkol berkelobot dan tanpa kelobot. Pemberian pupuk hayati dan amelioran disertai pupuk NPK 100% dan yang tanpa diberi amelioran menghasilkan bobot tongkol tanpa kelobot sebesar 1.089 g dan 1.064 g per tanaman. Pemberian pupuk hayati dengan amelioran dan pemberian pupuk NPK 100% menghasilkan bobot pipilan per tanaman 526,08 g dan 539,08 g. Aplikasi pupuk hayati dan amelioran organik belum mampu mengurangi dosis penggunaan pupuk NPK pada Inceptisols asal Pasir Banteng. Inceptisols generally have low to moderate soil fertility. The effort to increase the nutrients availability in Inceptisol through the application of NPK fertilizers need to be balanced with biofertilizers and organic ameliorants. This experiment aimed to reduce the dose of NPK fertilizer by using biofertilizers and organic ameliorants and to increase maizeyields. The experiment was conducted in Pasir Banteng, Sumedang Regency. The factorial RBD was used. The biofertilizer with organic ameliorant as the first factor: no biofertilizer and no ameliorant (control), biofertilizer, organic ameliorant, and combination of both. The second factor was dose of NPK fertilizer: 100%, 80%, 60%, 40% of recommended NPK dose. It was repeated three times. The results showed that there was interaction between biofertilizer, organic ameliorants, with NPK fertilizers on plant height, N-total soil, weight of cobs with and without husk. The application of biofertilizer and ameliorant with 100% NPK fertilizer and without ameliorant were 1,089 g and 1,064 g of cobs without husks, respectively. The application of biofertilizer with ameliorant and 100% NPK fertilizer had a grain weight of 526.08 g and 539.08 g, respectively. The application of biofertilizers and organic ameliorants has not been able to reduce the dose of NPK fertilizer on Inceptisols from Pasir Banteng.