Effects of saline stress on mineral composition, phenolic acids and flavonoids in leaves of artichoke and cardoon genotypes grown in floating system

Abstract

The results showed that the floating system could be considered an effective tool to improve quality aspects through proper management of the salt concentration in the nutrient solution. They also suggest that specific cultivars should be selected to obtain the desired profile of bioactive compounds.

Saline stress enhanced accumulation of leaf phenolics in honeysuckle ( Lonicera japonica Thunb.) without induction of oxidative stress

“…4c and d). Similar to other medicinal plants (Abrol et al, 2012;Colla et al, 2013;Ksouri et al, 2007;Shao et al, 2015), moderate saline stress was more beneficial to the accumulation of bioactive compounds in the leaves of honeysuckle ( Fig. 4c and d), as severe stress greatly reduced carbon supply for phenolic synthesis by inhibiting CO 2 assimilation.…”

“…After 80 min incubation at room temperature in the dark, the absorbance at 760 nm was measured. Total phenolics content was determined by using a standard curve plotted with known concentrations of gallic acid (Colla et al, 2013). Flavonoid content was measured by using differential spectrophotometry method with ZrOCl 2 $8H 2 O for avoiding the disturbance of chlorogenic acid (Zhou et al, 2007).…”

“…Under saline stress, plant antioxidant system is often stimulated to defense oxidative injury, and antioxidant capacity has been used as a criterion for the comparison of salt tolerance among crop cultivars (Ashrafi et al, 2015;Kiani-Pouya, 2015;Zhang et al, 2014). Phenolic compounds which are secondary metabolites have high ROS scavenging capacity, and accumulation of phenolics is commonly considered as a positive self-protection way to strengthen ROS scavenging ability in plants upon salt-induced oxidative stress (Abrol et al, 2012;Colla et al, 2013;Falleh et al, 2012;Ksouri et al, 2007;Shao et al, 2015;Zhao et al, 2015). Nevertheless, antioxidant activity of phenolic compounds is mainly proved by in vitro free radical scavenging experiments, and their roles in mitigating oxidative stress in vivo are still open to debate (Hernandez et al, 2009;Hernandez and Van Breusegem, 2010).…”

“…In Chinese, honeysuckle is a traditional medicinal plant, and has been widely used in healthcare, food and cosmetics industries. At present, studies attach importance to salt-induced changes in concentrations of bioactive phenolic compounds in medicinal plants (Colla et al, 2013;Karray-Bouraoui et al, 2010;Shao et al, 2015;Zhao et al, 2015). However, antioxidant mechanisms of phenolics in vivo are often overlooked, and the relation between accumulation of phenolics and antioxidant system induction under saline stress is less concerned.…”

Yield and Quality of Lettuce and Rocket Grown in Floating Culture System

“…Other cultivation features such as high salinity of nutrient solution (up to 4.8 mS cm -1 ), plant density and growing season could also affect yield and quality (nitrates, chlorophylls, vitamin C, carbohydrates and minerals content) of radish (Raphanus sativus), lamb's lettuce or corn salad (Valerianella locusta), rocket (Eruca sativa), artichoke (Cynara scolymus), cardoon (Cynara cardunculus), spiny chicory (Cichorium spinosum), and lettuce (Lactuca sativa) plants (Salerno et al, 2005;Fallovo et al, 2009a,b;Fontana and Nicola, 2009;Scuderi et al, 2009;Zanin et al, 2011;Colla et al 2012;Klados and Tzortzakis, 2014). Default et al (2006) reported that cultivation season affected significantly the growth rate and yield of six Cos type lettuce cultivars.…”