Physio-biochemical responses of sage genotypes to chilling

This study evaluated sage (Salvia officinalis L.) genotypes (cultivars: 'Berggarten', 'Icterina', 'Purpurascens', 'Tricolor', local Czech accessions from the Lednice region, South Moravia: 'LDN-1' and 'LDN-2') subjected to chilling (4 °C, 2 weeks, 18 °C ‒ control) for comparison of antioxidant defence systems. Chilling caused the most significant increase in the peroxidase activity in 'Purpurascens' and 'Tricolor', by 108.5% and 15.7%, respectively, while the catalase was unaffected by the low temperature. The phenolics increased in 'Purpurascens' and 'LDN-1' by 17.2% and 18.1%, respectively, and decreased in 'LDN-2' and 'Tricolor', by 10.6% and 11.7%, respectively, as a result of the chilling. In the sage treated with chilling, the scavenging of 2,2-diphenyl-1-picrylhydrazyl radicals (DPPH*) was higher (by 3%, on average), especially in 'Berggarten', 'Icterina', and 'Purpurascens', than in the control. However, the chilled 'LDN-2' and 'Tricolor' showed lower antioxidant∙ activity in comparison to the control. The malondialdehyde remained stable or was higher in the control, with the only exception being 'LDN-1', where its content increased by 11.4% in the chilled sage. In most genotypes, the content of the dry weight increased in the chilled plants by 9.4% on average. The responses of 'Icterina' and 'Purpurascens' to the low temperature was the most significant, but resulted from different physiological mechanisms. 'Purpurascens' showed the highest increase in the peroxidase activity due to the chilling, while the highest increase in the antioxidant activity was observed for 'Icterina'.