Abstract: In recent years, the national sugar demand has always been lower than the national sugar production. The imbalance is caused by sub-optimal cultivation and inefficiency of sugarcane fertilization. Efforts that can be done to improve the conditions are meeting the nutrients needs of sugar cane by N-fertilization according to the effective and efficient dosage, use high quality seeds, and planting the seeds with the appropriate systems. This study aimed to determine the effect of N fertilizer and cropping systems with some of seed placement to soil chemical properties, growth, and N uptake by sugarcane at ultisols in Tulang Bawang.The experiment was conducted in November 2015 - May 2016 at PT Sweet Indolampung, Tulang Bawang, Lampung. It was arranged in randomized complete block design (RCBD) two factors with three blocks as replication. The first factor was urea dosage consisting of 4 levels, i.e. without urea (U0), 165 kg/ha (U1), 329 kg/ha or standard fertilization of SGC (U2), and 494 kg/ha (U3). The second factor was cropping system with some of seed placement consisting of 6 levels, i.e. double row overlap of 25% (S1), double row overlap of 50% or standard use of SGC (S2), double row overlap 100% (S3), single row overlap 25% (S4), single row overlap of 50% (S5), single row overlap 100% (S6). The observations were done on several properties of soil chemical, nutrient uptake, and the plant growth variables. Data were analyzed using analysis of variance (ANOVA) at 5 % level, and continued with Duncan's Multiple Range Test (DMRT) at 5% level of significance. The results showed that there was no interaction between N fertilizing and cropping systems with variation of seed placement to all parameters (soil chemical properties, N uptake, growth, and production of sugarcane). Application of N fertilizer at ultisols in Tulang Bawang could not significantly affect soil pH, N-total, C-organic, and C/N ratio, but could significantly affect N uptake, efficiency of N uptake, plant height, leaf area, dry weight, and production of sugarcane aged 6 MAP. Meanwhile, cropping system with variation of seed placement could significantly affect soil pH, N-total, C/N ratio, N uptake, efficiency of N uptake, germination aged 40 DAP, population, plant height, leaf area, dry weight, and production of sugarcane aged 6 MAP. Application of 329 tons/ha of urea with cropping system of double row overlap 25% at ultisols in Tulang Bawang was the most effective and economic combination in improving soil fertility and stimulating growth and production of sugarcane aged 6 MAP. |