The Characteristics Of Cd Accumulation And Transport In Ratoon Rice And The Differences Among Varieties

Using Q Liangyousimiao,Chuangliangyou 33,Yongyou 4949,Shenliangyou 867,Hengfengyou 778,Yunliangyou 332,C Liangyou 343,and Y Liangyou 1577,a total of 8ratoon rice varieties were used as materials.Field ratoon test,hydroponic culture test with different Cd concentration gradients in the ratoon season,node cuttings test,and Sand culture node cuttings were carried out in 2021 to study the differences in Cd accumulation and transport characteristics in various organs and nodes of different varieties.The main conclusions are as follows:1.The Cd content of the first season rice showed the law of root>stem leaf>panicle>brown rice,and the Cd content of ratoon rice showed the law of root>rice stubble>stem leaf>panicle>brown rice;the Cd content of ratoon rice at different nodes was as follows:The low node(4^th inverse)>the high one(2^nd and 3^rd inverse),while the second and third are higher and lower;the difference in Cd content between the first season and the ratoon season is shown in two types:Q Liangyousimiao、Yongyou 4949 and Shenliangyou 867 showed the ratoon season>first season,and the other 5 varieties showed the first season>ratoon season.2.The Cd accumulation of each variety showed as the first season>ratoon season,and each node showed as high node>low node.The transport coefficient of Cd for each variety was higher than that of TF stem/root and TF stem/root in the ratoon season;The 5 varieties showed the ratoon season>the first season;the TF brown rice/panicle of 6 varieties was the first season>the ratoon season,and the TF brown rice/panicle of the 2 varieties was the ratoon season>the first season.3.65.74%and 44.94%of the Cd in the ratoon season of Shenliangyou 867 and C Liangyou 343 came from the root of the mother stem and the ratoon root absorbed from the soil.98.8%and 98.5%of the Cd accumulation in the 2^nd and 3^rd nodes of Shenliangyou 867in the cuttings came from the absorption from the soil during the ratoon season,respectively.99.6%and 98.1%of the Cd accumulation in the 2^nd and 3^rd nodes of C Liangyou 343 in the cuttings came from the absorption from the soil during the ratoon season.4.The Cd content of the ratoon rice in each node increased with the increase of the Cd concentration under the Cd concentration gradient treatment,and the Cd content of each organ showed that the underground part>stem and leaf>panicle>brown rice.The Cd absorption and accumulation of regenerative rice differed among cultivars.C liangyou 343had stronger Cd absorption ability than Shenliangyou 867.In the Cd pollution risk area,the varieties with weak Cd absorption ability and lower Cd concentration should be selecetd,and high stubble harvesting should be adopted,and supplemented by measures of Cd prevention,to ensure the production safety of ratoon-rice.