We compared the enzymatic antioxidative defence mechanisms of some regional subspecies of <I>Allium (A. cepa </I>L., <I>A. ascalonicum</I> auct. hort., A.<I> sativum</I> L.) cultivated mainly in the western regions of Romania, and two modern Hungarian climate resistant F <sub>1</sub> hybrids. The variability in the activities of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), glutathione reductase (GR) and glutathione S-transferase (GST) and their changes under soil moisture stress were investigated. 1-week-long water stress revealed that among three <I>Allium</I> species, relative water content decreased only in <I>A. ascalonicum</I> leaves (up to 16%). Unlike root enzymes, the activities of the shoot enzymes, especially POD, GR and GST showed a stronger correlation with the water content of the leaves after one week of water withdrawal; regression coefficients (<I>R</I><sup>2</sup>) were 0.359, 0.518 and 0.279, respectively. The ancient populations with elevated (or highly inducible) antioxidant enzyme activities may be interesting for further research and for breeding of new <I>Allium</I> varieties.
Effect of Super Absorbent Application on Antioxidant Enzyme Activities in Canola ( Brassica napus L.) Cultivars under Water Stress Conditions
