In Brazil, the potato cultivar Agata is used for fresh market, while the cultivar Markies is used for both fresh market and frying industry. However, these cultivars may respond differently to nitrogen (N) management. Thus, field experiments with these cultivars were conducted to evaluate marketable tuber yield and physico-chemical and nutritional quality of tubers in response to four different early N managements (80p: 80 kg N ha⁻¹ at planting; 160p: 160 kg N ha⁻¹ at planting; 40 + 120: 40 kg N ha⁻¹ at planting plus 120 kg N ha⁻¹ at hilling; and 80 + 80: 80 kg N ha⁻¹ at planting plus 80 kg N ha⁻¹ at hilling) combined with late N application rates at tuber bulking stage (0, 20, 40 and 80 kg N ha⁻¹). For both cultivars, the application of only 80 kg N ha⁻¹ at planting was enough to have satisfactory marketable tuber yield and the late N application did not provide benefit to yield. The 80 + 80 treatment reduced the concentrations of starch and carbohydrate and increased the protein concentration in tubers of cultivar Agata, and promoted the Ca biofortification of tubers in both cultivars. Tuber Fe concentration of cultivar Agata was higher with the 80p treatment. The early N managements with N supplied at planting increased tuber Cu concentration of both cultivars. Late N application increased the concentration of protein, Ca and Fe only in the Agata tubers. For cultivar Markies, the tuber reducing sugar concentration was increased by the late application of 40 kg N ha⁻¹ combined with the early N application treatments 160p and 40 + 120, but only small variations in the colour intensity or yellow tonality of the fried potatoes were observed.

在巴西，马铃薯品种Agata用于新鲜市场，而Markies品种用于新鲜市场和油炸行业。但是，这些品种对氮素管理的反应可能不同。因此，进行了田间试验用这些品种响应于评估商品薯收率和物理-化学和块茎的营养品质，以四种不同的早期Ñ管理层（80P：80千克氮公顷^-1在种植; 160P：160公斤氮公顷^-播种时为¹；播种时为40 + 120：40 kg N ha ^-1，丘陵时为120 kg N ha ^-1；播种时为80 + 80：80 kg N ha ^-1加80 kg N ha ^-1（在丘陵处）与块茎膨大阶段后期的氮肥施用量（0、20、40和80 kg N ha ^-1）结合。对于两个品种，仅施用80 kg N ha ^-1播种时的块茎产量足以使市场满意的块茎产量，而后期施氮对产量没有好处。80 + 80处理降低了Agata块茎块茎中淀粉和碳水化合物的浓度，增加了蛋白质含量，并促进了两个品种块茎的Ca生物强化。80p处理后，Agata品种的块茎铁浓度较高。种植时提供氮素的早期氮管理增加了两个品种的块茎铜浓度。后期氮肥施用仅增加了Agata块茎中蛋白质，Ca和Fe的浓度。对于Markies品种，后期施用40 kg N ha ^-1可增加块茎降低糖的浓度 结合早期的N施用处理160p和40 + 120，但仅观察到炸土豆的颜色强度或黄色调略有变化。