Abstract:
Taking ‘Beichen’(high accumulation) and ‘Jinfeng’(low accumulation) as test materials, pot experiments were conducted to explore the changes in biomass, photosynthetic respiratory system, and antioxidant defense system of two cabbage varieties under different degrees of Cd stress.The effects of Cd stress on the physiological and biochemical characteristics of cabbage varieties with high and low accumulation of Cd were studied, in order to provide reference of Chinese cabbage production.The results showed that when Cd stress concentration was 1.0 mg·kg
-1,chlorophyll content and biomass accumulation were inhibited, net photosynthetic rate(Pn),stomatal conductance(Gs),transpiration rate(Tr) and stomatal inhibition rate(Ls) were significantly decreased, and intercellular CO
2 concentration(Ci) was increased.With the increase of Cd stress concentration to 5.0 mg·kg
-1,MDA content and POD activity in ‘Beichen’ and ‘Jinfeng’ also showed an increasing trend(169.7% and 100.6%,respectively),and the activities of CAT,POD,APX,GR and DHAR in leaves of ‘Jinfeng’ with low accumulation were higher than that in ‘Beichen’ under various Cd concentration stress.To sum up, high and low Cd stress on accumulation cabbage physiological and biochemical characteristics of different response, low accumulation variaty because of CAT,POD,APX,GR,DHAR,high activity of ‘Beichen’,which under the stress of 5.0 mg·kg
-1 Cd ‘Beichen’ 63.7% higher than that of GR activity, less susceptible to Cd poisoning, lead to less Cd part is accumulated on the ground, at the same time, the higher antioxidant levels in blade can be resistant to Cd.