Biomass Accumulation, Marketable Yield, and Quality of Atlantic Potato in Response to Nitrogen

Potato (Solanum tuberosum L.) in Florida is largely produced in sandy soils with low water and nutrient holding capacity, which makes N fertilizer timing and rate key factors for successful crop management. The objective of this study was to determine the effect of N fertilizer rate and application timing strategy on biomass accumulation, marketable yield, and tuber quality of chipping potato cultivar Atlantic produced in northeastern Florida. Field trials were conducted for three consecutive years on three commercial farms. All plots received 56 kg ha(-1) of N before potato planting. Nitrogen fertilizer treatments were 0, 56, 112, or 168 kg ha(-1) at plant emergence (N-emerg) combined with 56 or 112 kg ha(-1) of N applied as sidedress at tuber initiation (N-tuber init). Aboveground plant biomass showed no response to increasing N at N-emerg or N-tuber init. Low yield and poor tuber quality were a result of intense rainfall patterns in the first year. For the other two seasons, marketable yield ranged from 28.7 to 36.1 Mg ha(-1). Nitrogen treatments at emergence were not correlated to an increase in potato yield during the final 2 yr indicating that under the conditions of these experiments there was no N limitation. Total N applications over 280 kg ha(-1) did not increase yield or quality and N-tuber init above 56 kg ha(-1) had no impact on plant biomass or tuber yield on any farm in any year of this study.