Hooker's or Warty Barberry? Physiological Background Analysis for Choosing the Right one into Ornamental Plantations Endangered by Drought

Abstract

Barberries as undemanding shrubs with high aesthetic value are often planted in city parks and street greeneries. However, severe urban environment combined with climate change puts pressure on these plants in terms of their ability to cope with drought. In order to avoid plantation fall-offs, a common garden experiment was carried out on the drought tolerance of two Asian barberry species, namely Hooker's barberry (Berberis hookeri Lem.) and warty barberry (Berberis verruculosa Hemsl. and Wils.). Higher leaf relative water content, postponed but more sensitive stomatal closure (decrease in stomatal conductivity for water) as well as osmotic adjustment (free proline accumulation) and antioxidant defence onset (total antioxidant activity of the hydrophilic phase), and faster photosynthetic pigment decomposition in Hooker's barberry transplants compared to warty barberry, point to better water management and advanced protection of leaf structures in this species under limited soil moisture. Moreover, warty barberry plants with half total leaf area suffered from drought earlier, because of enhanced soil water loss through evaporation. Thus, Hooker's barberry can be taken as more drought tolerant than its counterpart, therefore making it more suitable for plantings in areas that are prone to this environmental constraint.