【摘要】 为探明盐胁迫下微塑料对中华柽柳（Tamarix chinensis）种子萌发和幼苗生长的影响而进行多因子胁迫下柽柳种子发芽和幼苗生长响应关系试验，研究不同质量分数的微塑料（聚乙烯，PE,0.001%、0.01%、0.1%、0.25%、0.5%、0.75%、1%共7个梯度）、NaCl（0.1%、0.5%、1.0%、1.5%共4个梯度）和铵氮（NH₄Cl, 0.01%、0.025%、0.05%、0.075%、0.10%共5个梯度）单独或共同影响下柽柳种子发芽率、发芽指数、活力指数、平均发芽时间、恢复萌发率、最终萌发率以及柽柳幼苗株高、根长、鲜重、叶绿素含量、抗氧化能力等指标的响应关系。结果表明：盐度梯度下，低浓度（0.001%、0.01%和0.1%）微塑料对柽柳种子萌发和幼苗生长的抑制作用较强，中高浓度（0.25%、0.5%、0.75%和1%）微塑料对柽柳种子萌发和幼苗生长的抑制有所缓解甚至有所促进，其中各盐度下0.75%PE处理柽柳种子发芽率最高，随盐度增加，0.75%PE处理的柽柳种子发芽指数和活力指数均降低；0.25%、0.5%、0.75%和1%PE处理能够缓解盐胁迫对柽柳幼苗地上部长势的抑制作用；随盐度增加，微塑料处理下柽柳幼苗叶绿素含量有所下降，SOD、POD活性和MDA含量先上升后下降。综上，盐度梯度下，微塑料对柽柳种子萌发和幼苗生长的影响表现为“低抑制中高缓解”的趋势，随着盐度持续增加至1.0%和1.5%,微塑料这种缓解作用有所减弱。更多还原

【Abstract】 To explore the effects of microplastics on seed germination and seedling growth of Tamarix chinensis under salt stress, a multifactor stress experiment was conducted to analyze the response relationship of seed germination and seedling growth. The study examined the single or combined effects of different mass fractions of microplastics（polyethylene, PE, 0.001%, 0.01%, 0.1%, 0.25%, 0.5%, 0.75% and 1%, 7 gradients）, NaCl（0.1%, 0.5%, 1.0% and 1.5%, 4 gradients）, and ammonium nitrogen（NH₄Cl, 0.01%, 0.025%, 0.05%, 0.075% and 0.10%, 5 gradients） on indicators including seed germination rate, germination index, vigor index, mean germination time, recovery and final germination rates, as well as seedling traits such as plant height, root length, fresh weight, chlorophyll content, and antioxidant capacity. The results showed that under salinity gradients, low concentrations（0.001%, 0.01% and 0.1%） of PE exerted stronger inhibitory effects on seed germination and seedling growth, while moderate-to-high concentrations（0.25%, 0.5%, 0.75% and 1%） of PE alleviated these inhibitions or even promoted the seed germination and seedling growth. Among which, the germination rate of seeds treated with 0.75% PE was the highest in all salinity levels, and with the increase of salinity, the seed germination index and vigor index under 0.75% PE treatment were decreased. Treatments with 0.25%, 0.5%, 0.75% and 1% PE could alleviate the aboveground growth inhibition of seedlings under salt stress. With the increase of salinity, chlorophyll content of T. chinensis seedlings treated with microplastics were declined, while SOD and POD activities, and MDA content exhibited the trend of first increasing and then decreasing. Above all, under salinity gradients, the effects of PE exhibited a trend of low inhibition and moderate-to-high alleviation on seed germination and seedling growth of T. chinensis, and as salinity continued to increase to 1.0% and 1.5%, the alleviating effect of PE were weakened.更多还原