PHOSPHORUS AND ZINC INTERACTIONS IN CHELATOR-BUFFERED SOLUTION GROWN RUSSET BURBANK POTATO

High phosphorus (P) application in potato production potentially leads to antagonistic interactions with cationic micronutrients. None of the nine combinations of phosphorus and zinc (Zn) provided in chelator-buffer solution for 17 days to potato supported the concept of a P-induced Zn deficiency with regard to early season dry matter yield, especially when solution P ranged from sufficient to excessive-conditions under which P-Zn interaction traditionally is observed. Increased solution P at low Zn levels resulted in a steep increase of P in new and old shoot growth and an accumulation of manganese (Mn) in potato roots-a combination that might indirectly impact Zn nutrition in potato. Although high P levels in potato did not directly reduce Zn content or cause Zn deficiency, excessive P accumulation may reduce the activity of Zn by interacting with other micronutrients such as Mn.