Effects of Polystyrene Microplastics （PS-MPs） on Seed Germination and Seedling Growth of Hongyingzi Sorghum

The influences of polystyrene microplastics（PS-MPs） with two particle sizes（0.1 μm and 5 μm） on Hongyingzi sorghum seed germination and seedling growth were studied to explore the ecotoxicological effects of microplastics on crops.PS-MPs concentrations was designed with 0, 10, 50, 100, 200 and 400, 600 mg/L.The results showed that PSNPs（0.1 μm and 5 μm） had no significant effect on the germination rate, and the effect on seed vigor indexes such as germination potential, germination indexes, vigor indexes was different without significant difference, high concentration（400 mg/L and 600 mg/L）of 5 μm PS-MPs could significantly shorten the average germination time. The effect on the root length and bud length of Hongyingzi sorghum treated by PS-MPs（0.1 μm and 5 μm） generally increased first and then decreased with the change of concentration, 0.1 μm PS-MPs had significant promoting effect on root length and bud length, while 5 μm PS-MPs showed no significant.0.1 μm and 5 μm had no significant effect on the dry weight of seedlings.In conclusion, PS-MPS had no effect on seed germination, but treatment with 0.1 μm PS-MPs could significantly promote the growth of root length and shoot length.