Corn inbreds differing in efficiency to zinc

Abstract

Corn (Zea mays L.) inbreds H84 (Zn efficient) and A635 (Zn inefficient) were grown in solution culture with moderate (contaminants only) and high (10^‐4 M) levels of Zn and with 3 different phosphorus levels. Each of these treatments were with and without 10^‐4 M chelating agent EDTA. The upper shoots of the plants tended to have lower Zn concentrations in the Zn inefficient inbred than in the Zn efficient inbred, particularly at the low level of Zn application. This was independent of the P levels. In roots the opposite was observed at the low level of Zn application but at the high level of Zn the inefficient inbred had sometimes more and sometimes less than the Zn efficient inbred partly depending upon P level. The high Zn level was mildly toxic to both inbreds at the low P level and an Fe interaction was involved (induced Fe deficiency). The effect of P in increasing and decreasing Zn concentrations was not consistent. EDTA tended to decrease Zn uptake and, at the low P level, caused a much greater yield decrease for the Zn inefficient inbred than for the Zn efficient inbred.

Key words:

• Maize
• zinc
• phosphorus
• interactions
• micronutrients
• iron deficiency
• chelate