CORRELATION BETWEEN CUZN SUPEROXIDE-DISMUTASE AND GLUTATHIONE-REDUCTASE, AND ENVIRONMENTAL AND XENOBIOTIC STRESS TOLERANCE IN MAIZE INBREDS

A hypothesis was tested that there would be cross-tolerance between various oxidant stresses, using drought-tolerant and intolerant maize inbreds. Membrane leakage was measured to determine oxidant damage without needing quantification of the enzymes and other factors involved in protection. Paraquat and acifluorfen tolerances paralleled drought and SO2 tolerances using this test. Thus, membrane leakage caused by oxidant generating herbicides can also be used to predict drought tolerance; a much harder character to ascertain. Drought and photooxidative herbicide tolerances were both significantly correlated with high levels of CuZn superoxide dismutase (EC 1.15.1.1.) and with glutathione reductase (EC 1.6.4.2) activities. High levels of just superoxide dismutase or just glutathione reductase did not correlate with any of the tolerances. © 1990.