Tuber yield and quality of potato processing cultivars submitted to nitrogen rates

ABSTRACT Consumption of processed potatoes is increasing in Brazil. However, little information is available on the effect of nitrogen (N) rates on performance of potato cultivars developed in Brazil. The objective of this work was to evaluate yield and quality of tubers of potato processing cultivars, submitted to N rates at planting. Three field trials with eight treatments were conducted: two cultivars (Atlantic and BRSIPR Bel) and four N rates (0, 75, 150, and 225 kg/ha). Yield and quality of tubers were evaluated, as well as the post-frying absorbed oil content. Cultivar BRSIPR Bel showed higher total tuber yield (18% more) and commercial tuber yield (15% more) due to the production of higher number of tubers (29% more) compared to the cultivar Atlantic. On the other hand, Atlantic cultivar produced tubers with higher dry weight (22%) and lower oil absorption (38%). For both cultivars, the estimated N rate of 151 kg/ha resulted in the highest commercial tuber yield (diameter larger than 45 mm): 34.0 t/ha. For all studied variables there was no interaction between cultivar and N rate, concluding that the cultivars in this study (American and Brazilian origin) respond similarly to N rates.