激光预处理可保护蚕豆细胞免受UV-B辐射的损伤(英文)

Effects of laser pretreatment on cells of broad bean in UV-B-induced damage protection

当蚕豆的胚被 He- Ne激光 (632 .8nm,1 .63J· mm- 2 )照射 5min或被 CO2 激光 (1 0 60nm,2 .53J· mm- 2 )照射 1 min后 ,将其置入 Knop营养液中进行恒温培养。当蚕豆的上胚轴长到大约 3cm时 ,在光背景 (PAR)为 70μmol· m- 2 · s- 1条件下 ,分别用 1 .0 2、3.0 3、4.52 k J· m- 2 的 UV- B辐射蚕豆的上胚轴 7h。根据蚕豆丙二醛 (MDA)、抗坏血酸 (As A)和 UV- B吸收物的含量变化 ,来测试激光对 UV- B照射蚕豆的上胚轴的保护作用。结果显示 :激光预处理可保护蚕豆上胚轴对 UV- B辐射的作用。与对照组 (没有用 UV- B或激光照射 )、UV- B单独照射组比较 ,在激光预处理的条件下 ,MDA的含量明显减少 ,As A和 UV- B吸收化合物的含量增加。如先用激光处理 ,然后再用 UV- B辐射 ,UV- B吸收物的含量将比单独用激光和 UV-B处理获得更好的改善。从而认为 ,激光预处理能增强植物对 UV- B的抵抗力。

The embryos of broad bean ( Vicia faba L.) were irradiated for 5 min by a He Ne laser (632.8 nm,1.63 J·mm -2 ) or for 1 min by a CO 2 laser (1,060 nm,2.53 J·mm -2 ).Afterwards they were cultivated in Petri dish in the constant temperature incubator in Knop until the length of epicotyl of broad bean was perhaply 3 cm that could be treated by ultraviolet B (UV B) radiation.The epicotyl of broad bean was irradiated for 7 h by 1.02,3.03,4.52 kJ·m -2 UV B respectively in the ambient condition of 70 μmol·m -2 ·s -1 photosynthetically active radiation (PAR) in the growth cabinet.According to the changes of content of MDA,ascorbate acid (AsA) and UV B absorbing compounds (absorbance at 300 nm),the effects of protecting of laser to the epicotyl of broad bean from UV B radiation were tested.The results showed that laser pretreatment on the embryos could enhance the resistance of UV B stress in epicotyl.Comparing with the control (without UV B or laser radiation) and UV B radiation alone,the MDA content was decreased significantly while AsA content was increased in the condition of laser pretreatment.It was also found that laser pretreatment alone could improve the content of UV B absorbing compounds.If laser pretreatment followed UV B radiation,the content of UV B absorbing compounds was improved higher than laser treatment and UV B treatment respectively.We suppose that laser pretreatment could enhance stress resistance in plant by a pathway of increasing the content of AsA and UV B absorbing compounds while decreasing the MDA concentration.