Influence of seedpiece spacing and population on yield, internal quality, and economic performance of Atlantic, Superior, and Snowden potato varieties in eastern North Carolina

In recent stand assessment surveys on North Carolina farms, potato plant st ands averaged only 67% of target populations. In response to these findings , this study was designed to determine the effects of seedpiece spacing and varying seedpiece populations on yield, internal quality, and economics of three potato varieties commonly grown in North Carolina: Atlantic; Snowden ; and Superior. The three varieties responded differently to changes in spa cing and population. Atlantic was sensitive to differences in spacing and p opulations, with reduced yields of grade A tubers as spacing increased abov e 23 cm. Atlantic was not able to compensate for wide (46 cm) spacing, even when seedpiece populations were high (doubles planted every 46 cm). Yield of B tubers was greater for 15 cm spacing and decreased significantly as sp acing was increased. Yield of Superior was affected less by increases in sp acing than decreases in population. Superior was able to compensate for wid e gaps in spacing if seedpiece populations were high. Superior produced mor e B tubers at the 15 cm spacing, and less at the 46 cm spacing. Yield of gr ade A Snowden tubers did not differ with spacing or population; however, th ere were more B tubers in the 15 cm, 23 cm, and 46 cm (doubles) treatments than the wider spacing treatments. Incidence of hollow heart and heat necro sis increased in Atlantic in treatments that tended to have larger tubers. Economic analyses of data suggest that growers can significantly lncrease p rofit/hectare by optimizing spacing and populations with Atlantic and seedp iece populations in Superior.