The influence of nitrogen rates (287 and 120 kg/ha), planting density (32.000 and 40.000 plants/ha) and maturity at harvest (22 august and 18 september), on chip quality of "Agria” potato cultivar grown in Rioja country, were studied during six months of storage. The storage conditions has been: 10 ºC during 90 days, followed by cooling at 7 ºC during 70 days and after by conditioning at 14 ºC during 15 days.
The potatoes were analized for dry matter, sucrose, glucose, chip color and defects.
The date of harvest, only had significant effect on chip color that were lighter in more mature potatoes.
Growth treatment, with higher planting density and lower nitrogen rate, produced the best chip quality during storage.
Cooling at 7 ºC gived a big increase of sugars with high percentage of chip defects and dark chip color.
Conditioning at 14ºC during 15 days produced recovery of chip quality before cooling.