UV-B辐射对拟南芥种子萌发和幼苗生长的影响

以哥伦比亚生态型(Columbia-0)拟南芥(Arabidopsis thaliana)为实验材料, 人工模拟UV-B辐照处理拟南芥种子, 统计其发芽势和发芽率, 测定根长、株高、叶绿素、可溶性糖、可溶性蛋白以及丙二醛(MDA)含量, 研究UV-B辐照处理对拟南芥种子萌发和幼苗生长的影响。研究结果表明, 低剂量的UV-B辐照可以促进拟南芥种子萌发和幼苗生长, 并且最佳辐照剂量为1.0 kJ·m^–2(P<0.05), 此时的发芽势、发芽率、根长、株高、叶绿素、可溶性糖及可溶性蛋白的含量均达到最大, 而丙二醛的含量变化则不明显(P>0.05)。当辐照剂量大于1.0 kJ·m^–2时, 促进作用逐渐变小, 并且随着辐照剂量的增加, 表现出了抑制作用。实验结果表明, 适当剂量的UV-B辐照在一定程度上可以促进拟南芥种子萌发和幼苗生长, 而过高剂量的辐照则对其产生抑制或损伤作用。

Effect of UV-B Irradiation on Seed Germination and Seedling Growth of Arabidopsis

To explore the impact of UV-B irradiation on Arabidopsis seed germination and seedling growth, we treated seeds of Columbia wild-type Arabidopsis with artificial UV-B and examined germination potential, germination percentage, root length, plant height, and contents of chlorophyll, soluble sugar, soluble proteins and malonaldehyde (MDA). A short period of UV-B irradiation promoted Arabidopsis growth, with a significant effect at 1.0 kJ·m^–2 (P<0.05), with peak germination potential and percentage, as well as root length, plant height, and contents of chlorophyll, soluble sugar and soluble proteins. However, MDA content was not affected (P>0.05). With doses > 1.0 kJ·m^–2, the promotion was reduced and was inhibited with longer irradiation. Thus, suitable UV-B irradiation dose could promote seed germination and seedling growth of Arabidopsis, and a too-high dose is an inhibitor, inducing damage.