紫外线-B辐射对黄独微型块茎萌发与试管苗生长发育的影响

Effects of UV-B Irradiation on Microtuber Germination and Plantlet Growth and Development of Dioscorea bulbifera

为研究紫外线-B(UV-B)辐照处理对黄独微型块茎萌发和试管苗生长的影响,采用人工模拟不同紫外辐射强度对黄独试管苗进行辐射,组织培养后测定生理学指标。结果表明:1kJ/m2的UV-B辐射可以促进黄独微型块茎萌发和试管苗生长,与对照组相比,其发芽时间早,且其试管苗芽数、根数、叶片数、根长、株高、POD活性、SOD活性、总叶绿素含量、总可溶性糖含量和可溶性蛋白含量显著增加,但质膜透性、丙二醛含量和脯氨酸含量无显著变化。2kJ/m2和2.5kJ/m2的UV-B辐射则抑制黄独的萌发和试管苗生长,与对照组相比,其发芽率、芽数、根数、叶片数、根长、株高、POD活性、SOD活性、总叶绿素含量、总可溶性糖及可溶性蛋白含量显著下降,而质膜透性、丙二醛含量和脯氨酸含量显著增加。结论:1kJ/m2的UV-B辐射可以促进黄独微型块茎的提早萌发和试管苗生长,而高剂量的UV-B辐射则对其萌发和试管苗生长产生抑制作用。

In order to study the effects of UV-B irradiation on microtuber germination and plantlet growth and development of D.bulbifera,artificial UV-B and plant tissue culture were applied to determine the physiological indexes.Results:UV-B radiation at 1kJ/m2could promote their microtuber germination and palntlet growth of D.bulbifera,its germination was earlier,and its bud number,root number,leaf number,root length,plant height,the activity of POD,the activity of SOD,the content of total chlorophyll,the content of total soluble sugar and the content of soluble protein increased significantly compared with the control group,while the plasma membrane permeability,the content of MDA and the content of proline had no significant change.UV-B radiation doses of 2kJ/m2and 2.5kJ/m2inhibited the germination and plantlet growth of D.bulbifera,the rate of germination,bud number,root number,leaf number,root length,plant height,the activity of POD,the activity of SOD,the content of total chlorophyll,the content of total soluble sugar and the content of soluble protein decreased significantly compared with the control group,while the plasma membrane permeability,MDA and the content of proline increased significantly.Conclusion:UV-B radiation at 1kJ/m2 could promote their microtuber earlier germination and plantlet growth of D.bulbifera,but higher dose of UV-B radiation had an inhibition effects on its germination and plantlet growth.