不同微塑料赋存环境对小麦萌发与幼苗生长影响研究

为揭示不同微塑料赋存环境对小麦（Triticum aestivum L.）种子萌发和幼苗生长的影响，选取聚丙烯（Polypropylene，PP）、高密度聚乙烯（HDPE）和聚乳酸生物可降解塑料（PLA）3种微塑料，并分别设置3种微塑料粒径（150μm、1000μm和4000μm）和质量浓度（0.1g/kg、0.5g/kg和1g/kg）在自然环境条件下开展盆栽试验，通过统计分析和方差分析对不同微塑料组合处理下小麦种子的发芽率、发芽抑制率、生长特征及幼苗生长趋势进行分析.结果表明：不同微塑料胁迫下均降低了小麦种子平均发芽水平，小麦种子平均发芽抑制率呈现出HDPE>PLA>PP；微塑料的粒径和质量浓度处于中粒径和中浓度条件下对小麦种子的平均发芽抑制率最大分别为5.65%和4.55%，而处于低或高粒径和质量浓度条件下微塑料对小麦种子发芽的抑制作用有所减弱；微塑料粒径对小麦种子发芽率的影响作用较大，微塑料类型和质量浓度次之.与对照组相比微塑料HDPE和PLA对小麦种子生长特征指标（发芽势、发芽指数、活力指数和平均发芽时间）的影响作用比微塑料PP的影响作用更加显著，其中小麦种子活力指数受微塑料类型、粒径和质量浓度的影响最为显著.对照组和不同微塑料类型对小麦幼苗平均生长速率呈现出CK>PP>HDPE>PLA，而不同微塑料对小麦幼苗生长的抑制作用呈现为PLA>HDPE>PP，微塑料类型对小麦幼苗生长的影响作用最显著.

Effects of different microplastics occurrence environment on seed germination and seedling growth of wheat (Triticum aestivum L.)

In order to reveal the effects of different microplastics occurrence environment on seed germination and seedling growth of wheat (Triticum aestivum L.), the Polypropylene (PP), High Density Polyethylene (HDPE) and Biodegradable Polylactic Acid (PLA) were selected, the pot experiments were carried out in natural environment with the particle sizes (150μm, 1000μm and 4000μm) and mass concentrations (0.1g/kg, 0.5g/kg and 1g/kg), and the germination rates, germination inhibition rates, growth characteristics and seedling growth trends of wheat were analyzed by statistical analysis and variance analysis. The results showed that the average germination level of wheat seeds was reduced under different microplastics exposure, and the average germination inhibition rates of wheat seeds showed HDPE>PLA>PP; the average germination inhibition rates of wheat seeds under medium particle size and medium mass concentration of microplastics were the highest, which were 5.65% and 4.55%, respectively, while the inhibitory effects of microplastics on wheat seed germination were weakened at low or high particle size and mass concentration under low or high particle size and mass concentration of microplastics; the particle size of microplastics had a greater effect on the germination rate of wheat seeds, followed by the type and mass concentration of microplastics. The effects of microplastics HDPE and PLA on the growth characteristics of wheat seeds (germination potential, germination index, vigor index and average germination time) were more significant than those of microplastics PP compared with the control group, and the vigor index of wheat seeds was most significantly affected by the type, particle size and mass concentration of microplastics. The average growth rates of the control group and different types of microplastics on wheat seedlings showed CK>PP>HDPE>PLA, while the inhibitory effects of different microplastics on the growth of wheat seedlings showed PLA>HDPE>PP, and the type of microplastics had the most significant effect on the growth of wheat seedlings.