Abstract: In order to compare the characteristics of Cd accumulation and distribution of three high-quality late rice varieties,Tianyouhuazhan,Xing No.2 and Xiangwanxian No.13,in paddy field with heavy Cd contamination,a pot culture experiment was conducted under conditions of soil pH 6.65 and 2 mg/kg Cd added by men in soil.The results showed that:In organs of rice plant,Cd content of roots and stems was higher,and that in leaves and panicles was lower.Cd content parts of panicle showed the trend of branch > empty grain > filled grain.There existed significant difference in Cd content among varieties.Cd content in whole plant of Xing No.2 was highest,that of other two varieties was equal.Cd content in panicle,grain and brown rice showed the trend of Tianyouhuazhan > Xing No.2 > Xiangwanxian No.13.80.15%-89.33% of total Cd was accumulated before heading stage.From booting to harvest,Cd accumulation in leaves and stems was continuously increased,that in roots was reached top point at mid-filling stage,and Cd accumulation in panicle reached maximum at maturity.As for Cd accumulation of whole plant,Xing No.2 was highest,and Tianyouhuazhan was lowest.As for Cd accumulation in panicle,Tianyouhuazhan was highest,and Xiangwanxian No.13 was lowest.There existed varietal difference in distribution ratio of Cd in organs of rice plant.As for Xiangwanxian No.13,ratio of Cd accumulation in stems to whole plant was highest,and ratio of Cd accumulation in grains to whole plant was lowest,while Tianyouhuazhan showed the contrary trend.Yield per hill of Xiangwanxian No.13 was highest,that of Tianyouhuazhan was lowest,and the difference was significant.Under conditions in this study,Cd content in brown rice of Tianyouhuazhan was slightly higher than national standard(0.2 mg/kg),and that of Xing No.2 and Xiangwanxian No.13 was lower than national standard.These results showed that Xing No.2 and Xiangwanxian No.13 could realize rice safety production in paddy field with heavy Cd contamination.Comprehensively,Xiangwanxian No.13 was the better.

Key words: High-quality late rice, Cd, Yield, Accumulation and distribution, Variety comparison

CLC Number: 

• S511.01