鄂西北重金属污染农田玉米镉低积累品种筛选与综合评价OA

To screen maize(Zea mays L.)varieties with high yield potential and low-cadmium(Cd)accumulation for heavy metal-contaminated farmland in Northwest Hubei,a randomized block experiment was conducted on a heavy metal-contaminated farmland using 15 maize varieties.The agronomic traits,yield,and the contents of cadmium(Cd),lead(Pb),chromium(Cr),arsenic(As)and mercury(Hg)in grain of all varieties were determined.One-way analysis of variance(ANOVA)and the LSD method were adopt-ed to compare differences among varieties.The entropy weight-TOPSIS model was applied for multi-index comprehensive evaluation and ranking,and Pearson correlation analysis was used to explore the relationships between agronomic traits and grain Cd accumula-tion.The results showed that extremely significant differences(P＜0.001)existed in grain yield and grain Cd content among different maize varieties.The average yield ranged from 5.48 to 7.66 t/hm2,among which Tongyu 609,Tongyu 808 and Mengyu 298 presented relatively high yields.The top five varieties in the comprehensive evaluation by the entropy weight-TOPSIS model were Weike 702,Mengyu 298,Tongyu 808,Huayu 130 and Aiheyu 501.These superior varieties generally featured large biomass and robust stalks.Correlation analysis indicated that key above-ground agronomic traits(plant height,biomass)had no significant correlation with grain Cd accumulation.In conclusion,varieties including Weike 702,Mengyu 298 and Tongyu 808 exhibited high yield and low heavy met-al accumulation in heavy metal-contaminated farmland of Yunxi County.They were suitable for popularization and cultivation in this area and other similarly contaminated farmlands.