Physiological, Biochemical, and Metabolic Responses to Short and Prolonged Saline Stress in Two Cultivated Cardoon Genotypes

Abstract

Cultivated cardoon is a multipurpose crop with adaptability to limiting environments. Two genotypes (“Bianco Avorio” and “Spagnolo”) were comparatively characterized in response to short and prolonged 100 mM NaCl stress in hydroponics. Salt induced no growth variations between genotypes or symptoms of NaCl toxicity, but boosted ABA accumulation in roots and leaves. Both genotypes had high constitutive phenol content, whose major components were depleted upon 2 days of stress only in “Bianco Avorio”. Prolonged stress stimulated accumulation of proline, phenylpropanoids, and related transcripts, and non-enzymatic antioxidant activity. Decreased antioxidant enzymes activities upon short stress did not occur for APX in “Spagnolo”, indicating a stronger impairment of enzymatic defenses in “Bianco Avorio”. Nonetheless, H2O2 and lipid peroxidation did not increase under short and prolonged stress in both genotypes. Overall, the two genotypes appear to share similar defense mechanisms but, in the short term, “Bianco Avorio” depends mainly on non-enzymatic antioxidant phenylpropanoids for ROS scavenging, while “Spagnolo” maintains a larger arsenal of defenses. Upon prolonged stress, proline could have contributed to protection of metabolic functions in both genotypes. Our results provide cues that can be exploited for cardoon genetic improvement and highlight genotypic differences for breeding salinity tolerant varieties.

Effect of Salinity Stress on Growth and Metabolomic Profiling of Cucumis sativus and Solanum lycopersicum

“…Total antioxidant capacity (TAC) was reduced under salinity stress in tomato and increased in cucumber under low level of salinity. This is inconsistent with other reports which showed higher total antioxidant capacity under salinity stress [ 22 , 39 , 42 , 44 , 46 ]. Plant species differed from each other regarding the TAC due to their content from secondary metabolites accumulated after stress as TAC is correlated with the content of secondary metabolites present in plants either in normal conditions or under stress [ 47 , 48 , 49 ].…”

Chemical Composition of Cynara cardunculus L. var. altilis Bracts Cultivated in Central Greece: The Impact of Harvesting Time

“…This species has high nutritional, pharmacological, and industrial value, and, although it has been used since ancient times, it was only in the last decades that cardoon gained attention [5]. In addition to having multiple applications, it is a plant highly resistant to variations in climatic conditions and abiotic stressors, characteristic of the Mediterranean regions [6][7][8]. Widely consumed in typical Mediterranean…”

Strategies to Modulate Specialized Metabolism in Mediterranean Crops: From Molecular Aspects to Field

“…Plant SMs may undergo increase or decrease in their concentration in response to salinity-induced osmotic stress or specific ion toxicity. Salinity increased SMs and antioxidant potential in cotton (namely tannic acid, flavonoids and gossypol), in safflower plants growing under <100 mM of NaCl (flavonoids), in buckwheat (carotenoids, phenolic compounds and antioxidant activity), in artichoke and cultivated cardoon (flavonoids and chlorogenic acid) in response to moderate and high levels of salinity [ 25 ]. Increase in SMs in response to salt stress has been reported also in Rosmarinus officinalis , maize, wheat, pea, strawberry, spinach, Brassica oleracea , barley, basil, Matricaria chamomilla and some other spontaneous herbs ( Mentha pulegium , Nigella sativa ) [ 8 , 26 ].…”

“…Differently, a decrease in SMs was observed in lentil and Phaseolus vulgaris . The increase in SMs (i.e., polyphenols), induced by salinity stress, involves an improvement in the antioxidant activity in some important crops (wheat, buckwheat, artichoke, rice and cultivated cardoon), thus improving their nutritional quality [ 8 , 22 , 23 , 25 ]. Salt stress also resulted in a significant rise in alkaloid concentration in Achillea fragrantissima , Catharanthus roseus and Solanum nigrum .…”