影响长芒苋种子萌发因素的研究

Influence Factors on Seed Germination of Amaranthus palmeri

长芒苋是我国1985年发现的外来入侵植物,明确长芒苋种子萌发特性,将为其有效防控提供数据支撑。采用室内生物测定方法,对温度、光照、水势、发芽深度等影响长芒苋萌发的关键因子进行研究。结果表明,变温处理可有效提高长芒苋种子的发芽势和萌发率,最适萌发温度为35℃/15℃变温处理;在35℃/15℃培养条件下,光照对长芒苋种子的萌发影响不显著;当渗透势为-0.4~-0.2 MPa时,长芒苋种子的萌发率可达82.2%~100%,当渗透势为-0.8 MPa时,仍有36.7%的种子萌发;长芒苋种子的出苗率受播种深度的影响,在播种深度为0.5~1.0 cm时,萌发率最高。由此可见,长芒苋萌发具有广泛的环境适生范围,这也可能是其在我国大面积入侵的生态学基础。

Amaranthus palmeri,an invasive plant,was first recorded in China in 1985.Clarifying its seed germination characteristics will provide data support for its effective control.Laboratory experiments were conducted to examine the effect of key factors including temperature,light,osmotic stress and burial depth on the seed germination of A.palmeri.The germination potential and germination rate of A.palmeri could be effectively improved in changing temperature,and under the optimum temperature of 35℃/15℃ day/night,its seed germination was not affected significantly by light.Seed germination rate reached 82.2%~100% when the osmotic potential was -0.4~-0.2 MPa and 36.7% of the seeds still germinated when the osmotic potential was -0.8 MPa.The optimum burial depth for highest germination rate was 0.5~1.0 cm then decreasing with burial depth.Therefore,A.palmeri was strongly adapted to different environments providing it with the ability to its large-scale invasion in China.