Variations of Cd Absorption and Accumulation in Different Wheat Cultivars at Seedling Stage

The differences of Cd absorption and accumulation in 25 wheat cultivars at seedling stage were studied under hydroponic condition in order to screen the low Cd accumulation type of wheat cultivars.The results showed that these wheat cultivars had significant difference in absorption,accumulation,tolerance index,and transport efficiency of Cd when plants grown in water contaminated with 1 μmol·L-1 Cd.Cd had significant inhibitory effect on the shoot dry weight of wheat cultivars while the Cd effect on the root dry weight depended on the cultivars which decreasing the root dry weight in spring wheat cultivars but increasing the root dry weight in half-winter wheat cultivars.The Cd content in root varied from 33.1 to 139.7 mg·kg-1,the Cd accumulation in root varied from 2.12 to 9.78 μg·plant-1,the Cd content in shoot varied from 3.6 to 15.3 mg·kg-1,the Cd accumulation in shoot varied from 0.45 to 1.44 μg·plant-1,which showed that Cd was mainly accumulated in root not in shoot.Therefore,Cd accumulation in shoot could be adapted as screening indexes.And the 25 wheat cultivars were classified into three types:high Cd accumulation type,mean Cd accumulation type and low Cd accumulation type.