Abstract：
Microplastics (MPs) and copper (Cu) pollution coexist widely in cultivation environment. In this paper, polyvinyl chloride (PVC) were used to simulate the MPs exposure environment, and the combined effects of MPs + Cu on the germination of perilla seeds were analyzed. The results showed that low concentrations of Cu promoted seed germination, while medium to high concentrations exhibited inhibition and deteriorated the morphology of germinated seeds. The germination potential, germination index and vitality index of 8 mg • L-1 Cu treatment group with were 23.08%, 76.32% and 65.65%, respectively, of the control group. The addition of low concentration PVC increased the above indicators by 1.27, 1.15, and 1.35 times, respectively, while high concentration addition led to a decrease of 65.38%, 82.5%, and 66.44%, respectively. The addition of low concentration PVC reduced the amount of PVC attached to radicle. There was no significant change in germination rate. PVC treatment alone had no significant effect on germination. MPs + Cu inhibited seed germination, which was mainly reflected in the deterioration of seed morphology. Cu significantly enhanced antioxidant enzyme activity, increased reactive oxygen species (ROS) and MDA content. The addition of low concentration PVC enhanced SOD activity, reduced MDA and H2O2 content. The SOD activity of the Cu2+8 + PVC10 group was 4.05 and 1.35 times higher than that of the control group and Cu treatment group at their peak, respectively. At this time, the CAT activity of the Cu2+8 + PVC5000 group increased by 2.66 and 1.42 times, and the H2O2 content was 2.02 times higher than the control. Most of the above indicators reached their peak at 24 h. The activity of α-amylase was inhibited by different treatments, but β-amylase activity, starch and soluble sugar content did not change regularly. The research results can provide new ideas for evaluating the impact of MPs + Cu combined pollution on perilla and its potential ecological risk.
摘要：
微塑料（MPs）和铜（Cu）污染在栽培环境中广泛共存。在本文中,聚氯乙烯(PVC)用于模拟MPs暴露环境，并分析了MPs+Cu对紫苏种子萌发的综合影响。结果表明,低浓度的Cu能促进种子萌发,而中等至高浓度表现出抑制作用，并恶化了发芽种子的形态。发芽潜力，8mg•L-1Cu处理组的发芽指数和活力指数分别为23.08%,76.32%和65.65%，分别,对照组的。低浓度PVC的加入使上述指标分别提高了1.27、1.15、1.35倍，分别,而高浓度添加导致65.38%的下降，82.5%,和66.44%，分别。低浓度PVC的添加减少了附着在胚根上的PVC的量。发芽率无明显变化。单独的PVC处理对发芽没有显著影响。MPs+Cu抑制种子萌发,主要表现为种子形态的恶化。Cu显著增强抗氧化酶活性，增加活性氧（ROS）和MDA含量。低浓度PVC的加入增强了SOD活性，降低MDA和H2O2含量。Cu2+8+PVC10组的SOD活性在峰值时分别比对照组和Cu处理组高4.05和1.35倍,分别。此时,Cu2+8+PVC5000组的CAT活性分别提高了2.66和1.42倍,H2O2含量比对照高2.02倍。上述指标大多在24h达到峰值。不同处理对α-淀粉酶的活性均有抑制作用。但β-淀粉酶活性,淀粉和可溶性糖含量没有规律性变化。研究结果可为评价MPs+Cu复合污染对紫苏的影响及其潜在生态风险提供新思路。
