Table 7: Nitrogen rate × variety interaction in 2010 for rotten tubers as a percentage of total yield, marketable tuber yield, and total tuber yield for Russet potatoes grown on sandy loam soils in the Mid-Atlantic, averaged across N application timing.

Nitrogen rate Rotten tubers   Marketable yield   Total yield Goldrush Norkotah   Goldrush Norkotah   Goldrush Norkotah kg ha−1 Percentage of total yield kg ha−1 kg ha−1 0† 18.8 14.0 8507 7735 9839 8792 67 43.0 a‡ 12.2 bc 9239 c 21266 b 13593 d 23777 bc 134 48.2 a 8.6 c 8396 c 27409 a 14009 d 29957 a 201 21.7 b 11.6 bc 21100 b 26972 a 26121 abc 30360 a 268 20.4 b 13.2 bc 19000 b 2444 c 23309 c 28195 ab LSD0.10 10.6 4744 4812 Pr > F 0.0009 0.0033 0.0184

†No-fertilizer control plots were not included in Analysis of Variance and are included for informational purposes only. ‡Means within each dependent variable with the same letter are not significantly different (P ≥ 0.10, Fisher’s Protected LSD).