Abstract

Current study explored the effects of municipal sewage (MS) irrigation on heavy metal phyto-accretion, biochemical responses and human health risks of diverse wheat genotypes along with recycled municipal sewage (RMS). Mean concentrations of PO₄^3-, NO₃^--N, chemical oxygen demand, biological oxygen demand, K, Co, Cu, Cd, Cr and Ni were found higher in MS than irrigation criteria. This led to significant increase in heavy metal contents in roots, stem and grains of MS irrigated wheat genotypes compared to RMS and control treatments. No adverse health risk effects for individual or multiple metals were recorded in RMS irrigated wheat genotypes on grounds of lowest heavy metal accumulation. Multivariate techniques i.e. principal component analyses (PCA) and hierarchical agglomerative cluster analyses (HACA) identified tolerant (inefficient metal accumulators) and sensitive (efficient metal accumulators) wheat genotypes in MS and RMS. Tolerant wheat genotypes showed lowest accumulation of heavy metals, efficient biochemical mechanisms to combat oxidative stress and lower health risks to adults/children. Cultivation of identified tolerant wheat genotypes is recommended in areas receiving municipal wastes to reduce human and environmental health risks. Moreover, genetic potential of identified tolerant wheat genotypes from MS and RMS can be utilized in breeding heavy metal tolerant wheat germplasm worldwide.

摘要

当前的研究探索了市政污水（MS）灌溉对多种基因型小麦以及循环利用的市政污水（RMS）对重金属植物吸收，生化响应和人类健康风险的影响。PO的平均浓度₄ ^3-，NO ₃ ^-MS中的-N，化学需氧量，生物需氧量，K，Co，Cu，Cd，Cr和Ni比灌溉标准更高。与RMS和对照处理相比，MS灌溉小麦基因型的根，茎和籽粒中重金属含量显着增加。在RMS灌溉的小麦基因型中，没有以最低重金属积累为基础记录对单个或多种金属的不利健康风险影响。多变量技术，例如主成分分析（PCA）和层次聚集聚类分析（HACA），确定了MS和RMS中小麦基因型的耐受性（低效率的金属累积量）和敏感的（有效的金属累积量）小麦基因型。耐性小麦基因型显示出最低的重金属积累，有效的生化机制来对抗氧化应激并降低成人/儿童的健康风险。建议在接收城市废物的地区种植已鉴定的耐性小麦基因型，以减少对人类和环境健康的危害。此外，从MS和RMS鉴定出的耐性小麦基因型的遗传潜力可用于在全世界范围内育种重金属耐性小麦种质。