干旱条件下硅对草地早熟禾生长初期的影响

在聚乙二醇(PEG-6000)模拟干旱胁迫条件下,研究了5种硅肥(Na2SiO3)浓度对草地早熟禾Poapratensis种子萌发以及幼苗生长初期形态及生理指标的影响.结果表明:干旱胁迫会显著抑制早熟禾种子的萌发.使其幼苗萎蔫失水、叶片相对含水量降低、生物量下降;干旱胁迫下,硅可以显著提高早熟禾种子的发芽率和发芽势.并且干旱胁迫程度愈大硅的作用效果愈显著,同时硅能有效改善幼苗根系生长状况,利于早熟禾对养分和水分的吸收,提高叶片相对含水量和生物量,从而起到缓解干旱伤害的作用.但超过一定浓度时,硅也会抑制早熟禾的生长.

Effect of silicon fertilizer on early Kentucky bluegrass growth under drought stress

A experiment was conducted to determine the effect of combination of three PEG stress(5%,10%,15%) and five Silicon fertilizer(Na2SiO3:1,2,3,4,5 mmol/L) on seed germination and seedling growth of Kentucky bluegrass(Poa pretensis).This study showed that drought stress reduced the seed germination rate,the water content in leaves and the biomass of Kentucky bluegrass.Addition of Silicon increased seed vigor and germination rate,and was beneficial to root growth,which helpfully increased the uptake of water and nutrients by Kentucky bluegrass plants,such increased the water content in leaves and biomass.These implied that addition of silicon would alleviate the damage to Kentucky bluegrass plants resulting from drought stress.However,beneficial role of silicon was not available and even harmful to Kentucky bluegrass growth when silicon concentration was over high.