Effects Of Heavy Metal Pollution On Cadmium Accumulation Of Different Wheat Varieties And Study On Phytoremediation Of Heavy Metal By Intercropping

Soil is a resource that human beings rely on for survival and can not be regenerated or regenerated very slowly.With the development of modern industry,mining and pesticides using,heavy metal pollution has become increasingly serious.The study area is located in northearn Henan province,which is famous light industry city in China,whose battery factories’ number is about 200,production of large enterprises is more than 30,due to the limitation of technology conditions in last century,most of the production process,equipment level is poorer,pollution control was facilities humble,"three wastes" emissions caused heavy metal in part of local area’s soil exceeds the threshold.According to previous studies,heavy metals in farmland may not only affect the quality of agricultural products,but also enter the human body through the food chain,affecting the health of human beings.Therefore,taking appropriate measures to reduce the absorption of heavy metals in crops is the key to ensure the safe production of crops..Before the safe use of local farmland is carried out,it is extremely necessary to know the local heavy metal pollution and crop pollution.This study was in northern Henan farmland pollution caused by nickel cadmium battery production pollution,through a wide range of soil pollution area and crop pollution condition investigation,then using low accumulated crops and hyperaccumulation plants and crops intercropping technology to control the heavy metal in crop,respectively.However,due to the lack of screening for low-accumulation varieties of wheat in local areas,relevant studies on screening for low-accumulation varieties of field wheat were carried out,and the effects of different intercropping combinations of hyperaccumulat plants and maize on the control of cadmium content in maize grain were studied.The main research results of this paper are as follows:1)Investigation on soil and crop pollution in study areaAfter analyzing 87 soils and corresponding wheat samples collected in the irrigation area,it was found that the soil and wheat samples were mainly contaminated with cadmium,among which,the excess rate of Cd in soil was 94.25%,and the excess of Cd in wheat grain was 67.81%.The excess rate of other elements was Zn was 3.45% in soil,8.05% in wheat and nickel was 3.45% in wheat.The study on local residents’ intake risk of wheat shows that Zn and Cd are harmful to adults and children in some local areas,and Cu is harmful to local adults in some local areas.2)Differences in Cd Accumulation Between Wheat VarietiesEighteen wheat varieties were planted in the soil polluted by Cd.Traits such as plant height,uppermost internode length,number of grain per panicle,and the thousand grain weight were measured,and Cd concentrations in soil and different parts of wheat were also analyzed.The conclusion shows that there were significant differences between plant height,uppermost internode length,number of grain per panicle and the thousand grain weight.Cd accumulation in all parts showed leaf >stem>shell > grain,and the Cd concentration in stem was significantly positively correlated with the Cd concentration in shell and leaf,the Cd concentration in leaf were significantly positively correlated the Cd concentration in shell,and the Cd concentration in shell was significantly positively correlated with the Cd concentration in grain.The results of grain Cd concentration cluster analysis of wheat showed that Number 4,12 and 18 were three potential cultivars featuring low Cd-accumulation,whose name is Xi-nong 979,Xin-mai 26 and Zheng-mai 9023.3)Effects of different intercropping combinations of Solanum nigrum L and maize on cadmium accumulation in maizeThe conclusion shows that under different intercropping combinations,the Cd content in all parts of maize presented as root>leaf>stem> grain,all of which could achieve the purpose of reducing the Cd content in maize grain,and all of them could promote the concentration of Cd in both the aboveground and underground of Solanum nigrum L.In Single row maize and single row Solanum nigrum L intercropping,the 30 cm row spacing had the better effects on reducing the Cd concentration in maize grain;In double row maize and single row Solanum nigrum L intercropping,60 cm row spacing had better effect on reducing the Cd concentration in maize grain;The double rows of Solanum nigrum L had better effect on reducing the Cd concentration in maize grain than that of single rows of Solanum nigrum L.YL40120 and YL40120-2 are ideal solutions to deal with the contradiction between the interests of farmers and food safety in cadmium polluted farmland.