A Comparison of the Responses of Five Potato Cultivars To Chloride Stress From Either Sodium Chloride or Calcium Chloride

Abstract

Field trials were performed using the five following cultivars; Dark Red Norland, Russet Burbank, Superior, and Snowden. Randomized complete design with four replication swere conducted. Chloride salt treatments were given to plants twice after 7 and I 1 weeks of planting. The rate applied was about 100 kg per hectare from NaCI, CaCl2 or a combination of 50% NaCl and CaCl2. About 70 A grade tubers from each replicationwere cut and examined for internal defects after harvesting. The tissue calcium concentration of periderm and nonperiderm were then measured. From each replication, a composite sample of 20 tubers were combined for Ca analysis. Our results showed: (i) NaCl stress reduced tuber yield in all of the cultivars. This reduction was not as dramatic in the cultivar Superior. (ii) NaCl also reduced specific gravity by about 5% as well as tuber tissue calcium concentrations of cultivars. (iii) Same amount of chloride supplied from calcium chloride as a source increased tuber tissue calcium concentrations in all cultivars. However, there was no negative impact on either specific gravity or tuber yield. Results support our previous studies indicating that the negative impact of chloride on potato cultivars is only presented when NaCl is used as the source of chloride.