Effect of water management on four potato cultivars grown in the northeastern United States. II. Effect on crop quality.

摘要

The effects of water management and cultivar on the quality of the potato crop were examined in a field experiment at Aroostook Farm in Maine in 1992 and 1993. Treatments included six irrigation managements and four cultivars. Tuber specific gravitywas not influenced by water management treatments but was highly influenced by cultivar, with the highest values in cv. Atlantic and Russet Burbank, followed by Superior and Shepody which changed order between the two seasons. Irrigation did not markedly influence tuber external defects, but the rain-out treatment reduced growth cracks while its effect on misshapen tuber percent and total defects were inconsistent between the two seasons. The cultivar effect on misshapen tubers and total defects was significant both seasons, while its effect on sunburn, growth cracks and percent hollow heart was significant in the first season only. Russet Burbank and Shepody had the highest percent defects in the first season and switched order in the second, followed in both cases by Superior and Atlantic. Irrigation treatment, cultivar and their interaction had significant effects on tuber percent rot. The rain-out treatment resulted in less rot than other treatments, where for most cultivars, rot percent was seento increase with the increasing use of irrigation. Cv. Shepody, which had a very high tuber rot percentage, was the major exception, where the highest rot percentage was not associated with the highest water input. Tuber size distribution by percentageof total yield was not strongly influenced by irrigation treatment or by the rain-out treatment in either season, but varied between cultivars.