UV-B辐射对8个大豆品种种子萌发率和幼苗生长的影响

Effects of increased UV-B radiation on seed germination and seedlings growth of eight cultivars of Glycine max

在生长房 5种 (暗处、可见光、低、中、高强度紫外线 - B)处理下 ,研究了 8个大豆品种的种子萌发率和萌发后幼苗的生长状况。结果表明 ,暗处种子萌发率高于自然光和 UV- B辐射的种子。UV- B辐射增强对大豆种子的萌发率没有显著影响 ,仅使部分品种的最大萌发率降低和导致部分品种达到最大萌发率的时间延长。幼苗的生长对增强的 UV- B辐射非常敏感。使大部分品种的胚根变短增粗 ,这可能是植物激素作用的结果。大豆的叶绿素 a、叶绿素b和总叶绿素含量明显受到 UV- B辐射的抑制。 UV- B作用能促进类黄酮在幼苗中的积累 ,紫外吸收色素的增设有利于提高对 UV- B的抵抗力。UV- B辐射的这种效应及大豆品种间的差异在自然情况下会产生深远的生物学和生态学意义。

Eight cultivars of soybean (Glycine max (L.) Merr.) were exposed to visible light (220 μmol·m -2 ·s -1 ),three dose of UV B radiation (5,10,15 μW\5cm\+\{-2\}\5s\+\{-1\},respectively) and the dark to investigated the effects of enhanced UV B radiation on seed germination and seedlings growth.The results indicate that enhanced UV B irradiation had no effect on the germination of soybean cultivars,maximum germination,however,was influenced by UV B in some cultivars.In addition,UV B retarded the time up to their maximum germination.Germination in the dark was higher than visible light and increased ultraviolet B irradiance .Enhanced UV B radiation led to root of seedlings stunt and short.Chlorophyll a,chlorophyll b and total chlorophyll concentration were also reduced by enhanced UV B irratiation while flavonoids were stimulated.These UV B effect and differences between soybean cultivars would cause far reaching biological and ecological significance.