| 摘要: |
| 【目的】研究PEG-6000胁迫对宿根天人菊种子萌发及幼苗生理特性的影响，为研究该植物的抗旱机理提供依据。【方法】用PEG-6000模拟干旱胁迫，研究在不同质量分数（1%，2%，5%，10%，15%，20%，25%）PEG-6000胁迫下，宿根天人菊种子发芽率、发芽势、发芽指数及幼苗主根长、芽长、鲜质量、SOD活性和MDA含量的变化规律。【结果】 随PEG-6000质量分数的增加，宿根天人菊种子的发芽势、发芽率、发芽指数总体呈降低趋势，其中PEG-6000质量分数≥5%时，宿根天人菊种子的发芽势显著降低；PEG-6000质量分数≥15%时，种子发芽率极显著降低，25% PEG-6000处理的种子不能萌发。随PEG-6000质量分数的增加，宿根天人菊幼苗的芽长、鲜质量逐渐降低，主根长表现为先增加（1%～10%）后降低（10%～15%），SOD活性呈现先升（1%～5%）后降（5%～15%）趋势，MDA含量则逐渐增大。【结论】PEG-6000质量分数越大，对宿根天人菊种子萌发和幼苗生长的抑制作用越强，幼苗的细胞膜系统受伤害越大。 |
| 关键词: PEG-6000胁迫 宿根天人菊 种子萌发 幼苗生理特性 |
| DOI： |
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| 基金项目:湖北省豆类（蔬菜）植物工程技术研究中心开放基金项目（2012-01） |
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| Effects of PEG-6000 stress on seed germination and seedling physiological characteristics of Gaillardia aristata Pursh |
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ZHANG Feng-yin,CHEN Chan-you,HU Zhi-hui
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| Abstract: |
| 【Objective】The research was carried out to study the effects of polyethylene glycol (PEG-6000) stress on seed germination and seedling physiological characteristics of Gaillardia aristata Pursh.【Method】 Using PEG-6000 to simulate drought stress,the change of seed germination rate,germination vigor and germination index of G.aristata Pursh together with the main root length,stem length,fresh weight,SOD activity and MDA content of the seedlings were studied with different weight concentrations of PEG-6000 (1%,2%,5%,10%,15%,20% and 25%）.【Result】With the increase of PEG-6000 concentrations,the germination vigor,germination rate and germination index of the G.aristata seeds decreased generally.When PEG-6000 concentration was ≥5%,the germination vigor significantly decreased.When it was ≥15%,the germination rate significantly decreased.When it was 25%,the seed could not germinate.The stem length and fresh weight of the seedlings decreased gradually,while the main root length increased initially (1%-10%) followed by decrease (10%-15%).SOD activity increased initially (1%-5%) and then decreased (5%-15%),while MDA content increased gradually throughout.【Conclusion】The larger the PEG-6000 concentration was,the more severely the seed germination and seedling growth of G.aristata were influenced,and the more deeply the cell membrane system of G.aristata was damaged. |
| Key words: PEG-6000 stress Gaillardia aristata Pursh seed germination seedling physiological characteristics |
