UV-B辐射对拟南芥种子萌发和幼苗生长的影响

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

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1.0kJ·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1.0kJ·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。

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 ger- mination 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 seed- ling growth of Arabidopsis, and a too-high dose is an inhibitor, inducing damage.