We compared the enzymatic antioxidative defence mechanisms of some regional subspecies of Allium (A. cepa L., A. ascalonicum auct. hort., A. sativum L.) cultivated mainly in the western regions of Romania, and two modern Hungarian climate resistant F 1 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 Allium species, relative water content decreased only in A. ascalonicum 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 (R 2 ) 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 Allium varieties.

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Asparagus virus 1 (AV‐1) infects Asparagus officinalis L. (Asparagaceae) in the field worldwide. However, various wild relatives of A. officinalis are resistant to AV‐1. Here we study the behavior of the green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae), on 19 AV‐1‐resistant wild relatives of A. officinalis. We focus on behavior that is associated with regular cell penetration, relevant for inoculation of AV‐1, and sieve element penetration to check for vector resistance and its potential influence on AV‐1 transmission. Parameters, relevant for the transmission of non‐persistent viruses and host plant acceptance, were obtained by the electrical penetration graph technique. Furthermore, phylloclade architecture of A. officinalis and its wild relatives was examined to study its influence on aphid behavior. Behavior of M. persicae displays many cell penetrations and long ingestion periods on A. officinalis, compared to the generally shorter cell penetrations (reduced potential for virus transmission) and reduced or no ingestion (phloem‐located aphid resistance) on wild relatives. Because effects on aphid behavior are not consistent throughout the group of the tested wild relatives of A. officinalis, with some wild relatives being susceptible to M. persicae, a common genetic background for AV‐1 and aphid resistance appears to be unlikely. However, the reduced potential of virus transmission as well as aphid resistance shown by some wild relatives may be useful for future breeding programs.