Effect of Ice-Temperature and Spermidine on Chilling Sensitivity of Pepper

The peppers which were treated at ice-temperature for 6 hours and 1 mmol/L spermidine for 10 min, followed by cold storage (4 ̊C ± 1 ̊C) respectively were investigated. The results indicated that the chilling injury was delayed and reduced by ice-temperature and spermidine treatments. Comparing with control group, ice-temperature and spermidine exerted significant effects on reduction of ascorbic acid (Vc) and chlororphyll contents, relatively high activity of superoxide dismutase (SOD), accumulation of malondialdehyde (MDA) as well as the increase of cell membrane penetrability. The results indicated that the spermidine and ice-temperature induced the activity of antioxidant enzyme SOD and maintained higher defence-related compound Vc as well as lower levels of membrane lipid peroxidation, which may be associated with chilling injury alleviation. There was a difference between ice-temperature treatment and spermidine treatment after 30 days. The results suggested that spermidine was more effective in reducing chilling sensitivity and prolonging storage of peppers.