Effect of the proportion of ammonium -N and nitrate N, potassium and magnesium dosage on yield and quality of Virgina tobacco on vertisol soil type in Bodjonegoro (East Java, Indonesia)

إنجليزي. An experiment was conducted in dark-grey Vertisol soil type in Pekuwon, Sumberrejo, Bojonegoro in 1989. The aim of the experiment was to study the effect of N-NO3; N-NH4 proportion, the dosage of potassium and magnesium on yield and quality of Virginia FC tobacco. The experiment was arranged factorially in Randomized Block Design with three replications. The first factor were eight kinds of combination of N-NO3: N-NH4 proportion and dosage of potassium. The second factor were the dosage of magnesium i.e. 0 kg and 27 kg MgO per hectare. The recommended dosage of fertilizer was a result was 50 kg N (50 percent N-NO3+ 50 percent N-NH4) + 90 kg K2O + 90 kg P2O5 + 27 kg MgO per hectare equivalent to 122 kg AS + 192 kg PN + 200 kg TSP + 11 kg ZK + 100 kg kieserite per hectare

الأندونيسية. Penelitian dilakukan di tanah Vertisol kelabu tua di Desa Pekuwon, Sumberrejo, Bojonegoro pada musim tanam 1989. Tujuan penelitian untuk mengetahui pengaruh proporsi N-NO3: N-NH4, dosis kalium dan magnesium terhadap produksi dan mutu tembakau Virginia FC. Percobaan disusun secara faktorial dalam Rancangan Acak Kelompok dengan tiga ulangan. Perlakuan merupakan kombinasi beberapa faktor. Faktor pertama kombinasi proporsi N-NO3: N-NH4 dengan dosis kalium sebanyak delapan macam, faktor kedua adalah dosis Mg, yaitu 0 dan 27 kg MgO per hektar. Hasil penelitian menunjukan bahwa dosis pupuk yang direkomendasikan adalah 50 kg N (50 persen N-NO3 + 50 persen N-NH4) + 90 kg K2O + 90 kg P2O5 + 27 kg MgO per hektar atau setara dengan 122 kg ZA + 192 kg PN + 200 kg TSP + 11 kg ZK + 100 kg kiserit per hektar