Research On The Tolerance And Security And Enrichment Of Ramie Germplasm With Different Fineness Under Cadmium Stress

In order to study the enrichment,tolerance and safe utilization of different fineness of ramie germplasm under cadmium stress,this paper had carried out three aspects of research.Firstly,the comparison research of accumulation and enrichment of 20 different fineness of ramie germplasm under the low cadmium contaminated field.Secondly,the comparison research of tolerance of 12 different fineness of ramie germplasm under the high cadmium stress(0,25,75 and 150 mg/kg).Thirdly,the safe utilization of raw ramie on the cadmium contaminated field(soil cadmium background value:3.935mg/kg).Experiment?:Comparison of Accumulation?transfer and Enrichment of different fineness of ramie germplasm under the low cadmium contaminated fieldIn the low cadmium contaminated field,the cadmium enrichment coefficient of the test material was between 0.97 and 1.58,and the highest were“Xin 1~#(medium fineness)”,“Zhongzhu 1~#(medium fineness)",and“xiangsixian 1~#(high fineness)”,the enrichment coefficient followed by 1.58,1.55,1.54.the worst cadmium enrichment coefficient was“Huangping Qingma(high fineness)”,and the enrichment coefficient was 0.97.Screened out the ramie germplasm of high enrichment,“Xin 1~#”,“Xiangsixian 1#”and“Zhongzhu 1~#".The cadmium transfer coefficient of the test material was between 0.66 and 1.41,and the highest was“Leiyang Qingma(medium fineness)”,the transfer coefficient was 1.41.The accumulation of cadmium in the tested material was between 21861.68mg/hm~2~10233.63mg/hm~2,the highest was“C”,and screened out the ramie germplasm of high accumulation,“C”,“Zhongzhu 1~#"and“Pomoideae 1~#".And the cadmium accumulation were 21861.68mg/hm~2,19863.34mg/hm~2,17718.77mg/hm~2,respectively.We conclude that the fiber fineness of ramie does not affect its ability of cadmium enrichment.Experiment?:Comparative on the tolerance of different fineness of ramie germplasm under the high cadmium stressThe results showed that the comprehensive tolerance index of Cadmium for these 12investigated ramies under a Cadmium stress at 25 mg/kg was range from 0.80~1.18,with the best and worst Cadmium tolerance shown by“Xiangzhu 3~#(medium fineness)”and“Dazhu Huangbaima(low fineness)”,respectively;and under a Cadmium stress at 75 mg/kg was range from 0.09~0.77,with the best and worst Cadmium tolerance shown by“Zixing~#(medium fineness)”and“Liuyang Dayeqing(low fineness)”,respectively;and under a Cadmium stress at 150 mg/kg was range from 0.32~0.54,with the best and worst Cadmium tolerance shown by“Xiangsijian 1~#(high fineness)”and“Dazhu Huangbaima(low fineness)”,respectively.The Cadmium tolerance threshold of“Dazhu Huangbaima~#",“Ningxiang Chongtianpao",“Liuyang Dayeqing",“Linshui Qingdingjiama",“Chuanzhu 8~#",“Zhongzhu 1~#",“Wugang Hongpima",“Houpizhong 1~#"was 75 mg/kg,while the Cadmium tolerance threshold of“Xiangzhu 1~#",“Pomoideae 1~#",“Zixingma"and“Xiangsijian 1~#"was 150 mg/kg.In this experiment,four varieties of Ramie Germplasm with high cadmium tolerance“Xiangzhu 1~#",“Zixingma 1~#",“Zhongzhu 1~#"and“Xiangsixian 1~#"were screened out.We concluded that the cadmium tolerance of ramie germplasm has a certain relationship with the fineness,and the cadmium tolerance of medium and high fineness are greater than that of low fineness.Experiment?:Safe utilization of high fineness of Ramie under cadmium stressThe results showed that 92.14%%cadmium can be separated in the process of processing raw ramie to degummed ramie,the total cadmium and extraction of cadmium were0.27mg/kg and 0.0097mg/kg in degummed ramie,fully in the line with the national ecological textiles on the limits of heavy metal cadmium standards.