Nickel Level and Toxicity and Metabolism of Potato

Abstract

Heavy metals at some concentrations can cause inhibitions in, or alterations of, plant metabolism. Although beneficial at concentrations below 0.0001 mM, at high levels Ni can detrimentally affect yield and quality of vegetable crops. Affects of nickel on quality of potato (Solanum tuberosum L.) were studied because it takes up Ni easily and can accumulate in tubers and become ingested by humans. The cv. Chandramukhi was grown in refined sand and provided a complete nutrient solution for 40 days. On day 41 plants were separated into 7 lots. One lot was the control and treated with 0.0001 mM NiSO₄. In the other lots, nickel was applied at 0.05, 0.1, 0.2, 0.3, 0.4, and 0.5 as NiSO₄. At levels above 0.1 mM Ni there was reduced tuber concentrations of sugars, starch, and protein nitrogen and increased accumulation of nonprotein nitrogen and phenols in tubers. Levels of nonreducing sugars, starch, and phenols were increased in leaves as nickel concentration increased. Treatments above 0.0001 mM resulted in reduced sugar, starch, and protein contents in tubers.

Keywords:

• Solanum tuberosum
• Phenols
• Metabolism
• Tuber

Thanks are given to Professor C. Chaterjee for the use of laboratory facilities and guidance and to Prof. Yogesh Sharma and Dr. Rajeev Gopal.