微塑料与镉及其复合对小麦种子发芽的影响  

Effect of microplastics,cadmium,and their combination on wheat seed germination

作　　者：王晓晶 杨毅哲 曹阳 张东明 代允超[1] 吕家珑[1] WANG Xiaojing;YANG Yizhe;CAO Yang;ZHANG Dongming;DAI Yunchao;LÜJialong(College of Resources and Environment,Northwest A&F University,Key Laboratory of Plant Nutrition and the Agro-Environment in Northwest China,Ministry of Agriculture and Rural Affairs,Yangling 712100,China;Cultivated Land Quality and Agricultural Environment Protection Workstation of Shaanxi Province,Xi′an 710000,China)

机构地区：[1]西北农林科技大学资源环境学院,农业农村部西北植物营养与农业环境重点实验室,陕西杨凌712100 [2]陕西省耕地质量与农业环境保护工作站,西安710000

出　　处：《农业环境科学学报》2023年第2期263-273,共11页Journal of Agro-Environment Science

基　　金：国家自然科学基金项目(42007303);陕西省农业科技创新驱动项目(NYKJ-2021-YL(XN)19);黄土高原土壤侵蚀与旱地农业国家重点实验室基金项目(A314021402-2021012)。

摘　　要：为了解微塑料与镉单一及其复合污染对水培小麦发芽和幼苗生长的影响,选取农业土壤中普遍存在的两种微塑料[聚苯乙烯(mPS)和聚氯乙烯(mPVC),0、100、500 mg·L^(-1)和1000 mg·L^(-1)]、重金属镉(Cd,0、2、10 mg·L^(-1)和50 mg·L^(-1))和小麦种子为试验对象进行种子发芽试验。结果表明:单一微塑料污染下,mPS和mPVC对小麦种子发芽率的影响总体表现为低浓度促进、中高浓度抑制,其中mPVC对小麦种子的发芽指数、发芽势、平均发芽速度均有促进作用,mPS对小麦的生物量有促进作用;单一镉胁迫对小麦种子发芽率的影响基本表现为低浓度(2 mg·L^(-1))促进发芽,中高浓度(10 mg·L^(-1)和50 mg·L^(-1))抑制发芽,对小麦芽与根的影响基本表现为低促高抑的规律。微塑料和镉复合污染试验中,与对照组相比,低浓度镉(2 mg·L^(-1))-微塑料复合污染抑制小麦种子发芽,其余复合污染几乎对小麦种子的发芽无影响;而低浓度的mPVC与镉复合对小麦种子发芽指数、活力指数、平均发芽速度、根芽的生长和含水率等起协同作用。研究表明,与单一污染处理相比,微塑料-镉复合污染对小麦种子发芽势、活力指数、芽长和生物量的影响基本表现为拮抗作用,即两者复合在一定程度上降低了单一污染物的毒性。To understand the effects of microplastics,cadmium,and their combination on germination and growth of hydroponic wheat,two common microplastics[polystyrene(mPS)and polyvinyl chloride(mPVC)](0,100,500 mg·L^(-1),and 1000 mg·L^(-1)),heavy metal cadmium(Cd)(0,2,10 mg·L^(-1),and 50 mg·L^(-1)),and wheat seeds in agricultural soil were selected for seed germination testing.The results showed that overall,mPS and mPVC promoted wheat seed germination at low concentrations,but inhibited wheat seed germination at medium and high concentrations.mPVC promoted the germination index,germination potential,and average germination rate of wheat seeds,whereas,mPS promoted wheat biomass.Cd promoted wheat seed germination at a low concentration(2 mg·L^(-1)),but inhibited wheat seed germination at medium and high concentrations(10 mg·L^(-1) and 50 mg·L^(-1)).The effect on wheat buds and roots followed the rule of low promotion and high inhibition.When the combined effect of microplastics and cadmium was tested,compared with the control group,low concentration of Cd(2 mg·L^(-1))-microplastic inhibited wheat seed germination,but had almost no effect on wheat seed germination.Low concentration of mPVC combined with Cd had synergistic effects on wheat seed germination index,vigor index,average germination rate,root bud growth,and water content.In summary,the combined microplastic-cadmium pollution had antagonistic effects on wheat seed germination potential,vigor index,bud length,and biomass,thereby indicating that the combination of the two pollutants had a reduced toxicity compared to that of either pollutant.

关 键 词：小麦 微塑料 镉 复合污染 种子发芽 幼苗生长 

分 类 号：X173[环境科学与工程—环境科学]