The Effect of Cu on Ultrastructure of Wheat

Transmission electron microscope (TEM) was used to investigate the damage of wheat seedlings by copper and the distribution of Cu²⁺ in different parts of wheat seedlings was discussed. Experiment showed that Cu is more susceptible to migration than other metals in wheat cells. Needle dark electron dense particles were existed in leaves cells with 5 mg/L Cu stressed. Swollen cristae in mitochondria were existed in cells with 50 mg/L stressed, while mitochondria were almost disappear with 100 mg/L stressed. Chloroplast increased in wheat leaves under low concentration Cu²⁺ stressed while swollen chloroplast and disrupted chloroplast membrane and cascade structure damaged of chloroplast stroma were existed under high concentration. The inference of Cu²⁺ on wheat root nucleolus was serious. Disruption of nuclear membrane, multi-vesicle nucleoplasm and agglutination of nucleus chromatin were appeared at root cells under 50 mg/L Cu²⁺ and more serious damage were appeared under 100 mg/L Cu²⁺.