摘要
为探究重金属、微塑料和二者的复合效应对农作物种子生长特性的影响,选取水稻种子为实验对象,探究微塑料聚苯乙烯(mPS)和聚对苯二甲酸类塑料(mPET,100、300、500、1000 mg·L^-1和1500 mg·L^-1)与重金属镉(Cd,2、5、10 mg·L^-1和50 mg·L^-1)单一及复合对种子萌发及生长的影响。结果表明:单一实验中,镉胁迫对水稻种子萌发特性的影响基本表现为“低促高抑”的规律,随着镉浓度的升高,发芽率、发芽势、发芽指数、活力指数以及根长和芽长等各项指标均呈现下降的趋势;单一微塑料暴露下,总体表现为低浓度(100 mg·L^-1)促进发芽,中浓度(500 mg·L^-1)抑制发芽,高浓度(>1000 mg·L^-1)无影响,即发芽率与对照组持平;两种微塑料对水稻种子的活力指数、根长和芽长均有所促进。微塑料(100 mg·L^-1和500 mg·L^-1)和镉(2 mg·L^-1和10 mg·L^-1)复合污染实验中,与对照组相比,低浓度MPs(100 mg·L^-1)-Cd(2 mg·L^-1)复合产生的协同作用促进了水稻种子发芽,其余复合污染对种子的发芽均表现为拮抗作用;对于低浓度的微塑料(100 mg·L^-1),其与镉复合会对水稻种子芽和根的生长起协同作用,只有mPS(100 mg·L^-1)与高浓度的镉(10 mg·L^-1)复合才会对根的生长起到拮抗作用;高浓度的微塑料与高浓度的镉复合后没有对水稻种子根和芽产生影响。研究表明,相比于单一污染,微塑料-镉复合效应对水稻种子生长特性、根长和芽长的影响总体表现为拮抗作用,一定程度上降低了单一污染物的毒害作用。
To better understand the effects of heavy metals and microplastics(MPs)on the growth characteristics of crop seeds,in this study,we investigated the single and combined effects of microplastics,including polystyrene(mPS)and polyethylene terephthalate(mPET)(100,300,500,1000 mg·L^-1,and 1500 mg·L^-1)and the heavy metal Cd(2,5,10 mg·L^-1,and 50 mg·L^-1)on germination and growth of rice(Oryza sativa L.)seeds.The results showed that single effect of Cd at a low concentration promoted rice seed germination but inhibited it at a high concentration.With the increase in Cd concentration,a more severe inhibition was observed in the germination rate,germination potential,germination index,vigor index,root length,and bud length of the rice seeds.Furthermore,a low concentration(100 mg·L^-1)of MPs promoted germination while a medium concentration(500 mg·L^-1)inhibited germination.However,a high concentration(>1000 mg·L^-1)had no effects on seed germination.Both mPS and mPET promoted the vigor index,root length,and bud length of rice seeds.The results of combined effects of MPs(100 mg·L^-1 and 500 mg·L^-1)and Cd(2 mg·L^-1 and 10 mg·L^-1)showed that low concentration of MPs(100 mg·L^-1)and Cd(2 mg·L^-1)had synergistic effects on seed germination,while the other combinations had antagonistic effects on germination.Although combined low concentration of MPs(100 mg·L^-1)and Cd had synergistic effects on the bud and root growth of rice seeds,low concentration of MPs(100 mg·L^-1)combined with a high concentration of Cd(10 mg·L^-1)had antagonistic effects on the root growth.However,high concentrations of MPs combined with high concentrations of Cd did not affect the root and bud growth of rice seeds.Our results indicated that,compared with single effect,combined effects of MPs and Cd on the growth characteristics,root length,and bud length of rice seeds were generally antagonistic,which reduced their toxic effects as a single pollutant.
作者
王泽正
杨亮
李婕
付东东
胡维薇
范正权
彭丽成
WANG Ze-zheng;YANG Liang;LI Jie;FU Dong-dong;HU Wei-wei;FAN Zheng-quan;PENG Li-cheng(College of Ecology and Environment,Hainan University,Haikou 570100,China;Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province,Haikou 570100,China;Pujin Environmental Engineering(Hainan)Co.Ltd,Haikou 570105,China)
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2021年第1期44-53,共10页
Journal of Agro-Environment Science
基金
海南省自然科学基金高层次人才项目(2019RC043)
国家自然科学基金项目(41766003)
海南大学D类高层次人才科研启动经费(kyqd(zr)1719)。
关键词
微塑料
镉
复合效应
水稻
种子发芽
生长特性
microplastics
cadmium
combined effects
rice
seed germination
growth characteristics