Abstract:
【Objective】 Study on the effect of Zn on maize seed germination and growth under microplastics.
【Methods】 The effects of different single and combination treatments of zinc (Zn) and three microplastics: polyethylene (PE), polypropylene (PP) and polyvinyl chloride (PVC) on the germination of maize seeds and their growth was investigated using maize seeds.
【Results】 Maize seed germination, germination index, germination potential, vigor index, stem length, and root length generally showed a decreasing trend with increasing concentrations of Zn mono-treatment.The three microplastics had slight effects on the germination and growth of maize seeds compared to Zn.Maize germination, maize germination index, germination potential, and vigor index were greater in the combined Zn and microplastic treatments than in the corresponding Zn mono-treatment.Maize germination was 14.29%, 14.29%, and 9.52% higher under 50 mg/L Zn + 100 mg/L PE, 50 mg/L Zn + 100 mg/L PP, 50 mg/L Zn + 100 mg/L PVC treatments, respectively, as compared to 50 mg/L Zn mono-treatment.Germination index, germination potential, and vigor index were 59.10%, 76.91%, and 131.16% higher under 100 mg/L Zn+PE100 mg/L PE treatment and 15.76%, 39.53%, and 15.47% higher under 50 mg/L Zn+100 mg/L PVC treatment compared to 100 mg/L Zn treatment, respectively.Maize seed stem and root length increased with increasing PE concentration under 50 mg/L Zn+PE treatment.For Zn+PP treatments, maize stem lengths were all lower than the corresponding Zn mono-treatments, and root lengths were 45.35% higher at 50 mg/L Zn+100 mg/L PE compared to 50 mg/L Zn, 45.20% higher at 50 mg/L Zn+100 mg/L PP compared to 50 mg/L Zn, and greatest at 50 mg/L Zn+100 mg/L PVC compared to 50 mg/L Zn by 55.91%.
【Conclusion】 The addition of lower concentrations (100 mg/L) of microplastics significantly improves the tolerance of maize seeds to excess Zn and promotes seed germination and growth.