Evaluation of physiological responses and tolerance to low-temperature stress of four Iceland poppy (Papaver nudicaule) varieties

摘要

ABSTRACTIceland poppy (Papaver nudicaule) is a boreal flowering plant and native to subpolar regions of Europe, Asia and North America, and the mountains of Central Asia. To investigate response and tolerance to low-temperature stress, the four varieties of Iceland poppy, Champagne Bubbles (CB), Domestic Variety (DV), Wonderland (WL), and Garden Gnome (GG), were subjected to low-temperature treatment from 0°C to −9°C. The relative electrical conductivities in four varieties increased along with the decrease in temperature. Treated by −3°C, the morphological changes of seedlings at different time points were investigated. Four varieties were differentially injured by freezing temperature. The dynamic accumulations of malondialdehyde (MDA), free proline (FP), soluble proteins (SP), and activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) during low-temperature treatment were measured and compared. A minor change in SP content during treatment was found, whereas MDA and FP were sign...