PEG模拟干旱胁迫对凤仙花种子萌发及幼苗生长的影响

Effects of PEG Imposed Drought Stress on the Seed Germination and Seeding Growth of Impatiens Balsamina

摘要: 采用不同质量分数（0，2%，5%，10%，15%，20%（W/V））的PEG渗透胁迫凤仙花（Impatiens balsamina）种子，研究PEG处理对凤仙花种子萌发及幼苗生理特性的影响. 结果表明：在上述质量分数范围内，凤仙花种子的发芽率、发芽势、发芽指数、活力指数以及幼苗的茎长、根长、侧根数及鲜重均随PEG质量分数的增加呈现下降的趋势；当PEG质量分数高于10％时，幼苗体内SOD活性和POD活性降低，而MDA含量增加，表明凤仙花种子萌发和幼苗生长的抑制作用以及细胞膜受伤害程度随PEG质量分数的增加而加重.

Abstract: Effects of PEG osmotic stress on seed germination and physiological characteristics of Impatiens balsamina seedlings were investigated by using different concentrations of PEG (0, 2%, 5%, 10%, 15%, 20% (W/V)). The results indicated that the germination rate, germination potential, germination index, vigor index, bud length, root length, number of lateral root and fresh weight all decreased gradually with the increasing concentration of PEG .while its MDA content increased gradually and the activity of SOD and POD in seedlings decreased gradually with PEG concentration more than 10%. The results showed that the higher concentration of PEG was used, the higher inhibition on seed germination and seedling growth or more sever damage on cell membrane was obtained.